fix inaccuracies (#10142)

* Prepare changelog for v0.34.24

Signed-off-by: Thane Thomson <connect@thanethomson.com>

* Bump version to 0.34.24

Signed-off-by: Thane Thomson <connect@thanethomson.com>

Signed-off-by: Thane Thomson <connect@thanethomson.com>

.circleci/config.yml

@@ -0,0 +1,168 @@
+version: 2.1
+
+executors:
+  golang:
+    docker:
+      - image: tendermintdev/docker-tendermint-build
+    working_directory: /go/src/github.com/tendermint/tendermint
+    environment:
+      GOBIN: /tmp/bin
+  release:
+    machine: true
+  docs:
+    docker:
+      - image: tendermintdev/docker-website-deployment
+    environment:
+      AWS_REGION: us-east-1
+
+commands:
+  run_test:
+    parameters:
+      script_path:
+        type: string
+    steps:
+      - attach_workspace:
+          at: /tmp/bin
+      - restore_cache:
+          name: "Restore source code cache"
+          keys:
+            - go-src-v1-{{ .Revision }}
+      - checkout
+      - restore_cache:
+          name: "Restore go modules cache"
+          keys:
+            - go-mod-v1-{{ checksum "go.sum" }}
+      - run:
+          name: "Running test"
+          command: |
+            bash << parameters.script_path >>
+jobs:
+  setup_dependencies:
+    executor: golang
+    steps:
+      - checkout
+      - restore_cache:
+          name: "Restore go modules cache"
+          keys:
+            - go-mod-v1-{{ checksum "go.sum" }}
+      - run:
+          command: |
+            mkdir -p /tmp/bin
+      - run:
+          name: Cache go modules
+          command: make go-mod-cache
+      - run:
+          name: tools
+          command: make tools
+      - run:
+          name: "Build binaries"
+          command: make install install_abci
+      - save_cache:
+          name: "Save go modules cache"
+          key: go-mod-v1-{{ checksum "go.sum" }}
+          paths:
+            - "/go/pkg/mod"
+      - save_cache:
+          name: "Save source code cache"
+          key: go-src-v1-{{ .Revision }}
+          paths:
+            - ".git"
+      - persist_to_workspace:
+          root: "/tmp/bin"
+          paths:
+            - "."
+
+  deploy_docs:
+    executor: docs
+    steps:
+      - checkout
+      - run:
+          name: "Pull versions"
+          command: git fetch origin v0.32 v0.33
+      - run:
+          name: "Build docs"
+          command: make build-docs
+      - run:
+          name: "Sync to S3"
+          command: make sync-docs
+
+  prepare_build:
+    executor: golang
+    steps:
+      - restore_cache:
+          name: "Restore source code cache"
+          keys:
+            - go-src-v1-{{ .Revision }}
+      - checkout
+      - run:
+          name: Get next release number
+          command: |
+            export LAST_TAG="`git describe --tags --abbrev=0 --match "${CIRCLE_BRANCH}.*"`"
+            echo "Last tag: ${LAST_TAG}"
+            if [ -z "${LAST_TAG}" ]; then
+              export LAST_TAG="${CIRCLE_BRANCH}"
+              echo "Last tag not found. Possibly fresh branch or feature branch. Setting ${LAST_TAG} as tag."
+            fi
+            export NEXT_TAG="`python -u scripts/release_management/bump-semver.py --version "${LAST_TAG}"`"
+            echo "Next tag: ${NEXT_TAG}"
+            echo "export CIRCLE_TAG=\"${NEXT_TAG}\"" > release-version.source
+      - run:
+          name: Build dependencies
+          command: make tools
+      - persist_to_workspace:
+          root: .
+          paths:
+            - "release-version.source"
+      - save_cache:
+          key: v2-release-deps-{{ checksum "go.sum" }}
+          paths:
+            - "/go/pkg/mod"
+
+  # # Test RPC implementation against the swagger documented specs
+  # contract_tests:
+  #   working_directory: /home/circleci/.go_workspace/src/github.com/tendermint/tendermint
+  #   machine:
+  #     image: circleci/classic:latest
+  #   environment:
+  #     GOBIN: /home/circleci/.go_workspace/bin
+  #     GOPATH: /home/circleci/.go_workspace/
+  #     GOOS: linux
+  #     GOARCH: amd64
+  #   parallelism: 1
+  #   steps:
+  #     - checkout
+  #     - run:
+  #         name: Test RPC endpoints against swagger documentation
+  #         command: |
+  #           set -x
+  #           export PATH=~/.local/bin:$PATH
+  #           # install node and dredd
+  #           ./scripts/get_nodejs.sh
+  #           # build the binaries with a proper version of Go
+  #           docker run --rm -v "$PWD":/go/src/github.com/tendermint/tendermint -w /go/src/github.com/tendermint/tendermint golang make build-linux build-contract-tests-hooks
+  #           # This docker image works with go 1.7, we can install here the hook handler that contract-tests is going to use
+  #           go get github.com/snikch/goodman/cmd/goodman
+  #           make contract-tests
+
+workflows:
+  version: 2
+  docs:
+    jobs:
+      - deploy_docs:
+          context: tendermint-docs
+          filters:
+            branches:
+              only:
+                - master
+            tags:
+              only:
+                - /^v.*/
+      - deploy_docs:
+          context: tendermint-docs-staging
+          filters:
+            branches:
+              only:
+                - docs-staging
+      # - contract_tests:
+      #     requires:
+      #       - setup_dependencies

.github/CODEOWNERS

@@ -7,6 +7,5 @@
 # global owners are only requested if there isn't a more specific
 # codeowner specified below. For this reason, the global codeowners
 # are often repeated in package-level definitions.
-*     @ebuchman @tendermint/tendermint-engineering
+*     @ebuchman @tendermint/tendermint-engineering @adizere @lasarojc
 
-/spec @ebuchman @tendermint/tendermint-research @tendermint/tendermint-engineering

.github/ISSUE_TEMPLATE/bug-report.md

@@ -1,18 +1,13 @@
 ---
-name: Bug report
+name: Bug Report
 about: Create a report to help us squash bugs!
 
 ---
 <!--
-
 Please fill in as much of the template below as you can.
 
-If you have general questions, please create a new discussion:
-https://github.com/tendermint/tendermint/discussions
-
-Be ready for followup questions, and please respond in a timely manner. We might
-ask you to provide additional logs and data (tendermint & app).
-
+Be ready for followup questions, and please respond in a timely
+manner. We might ask you to provide additional logs and data (tendermint & app).
 -->
 
 **Tendermint version** (use `tendermint version` or `git rev-parse --verify HEAD` if installed from source):

.github/ISSUE_TEMPLATE/config.yml

@@ -1,5 +0,0 @@
-blank_issues_enabled: true
-contact_links:
-  - name: Ask a question
-    url: https://github.com/tendermint/tendermint/discussions
-    about: Please ask and answer questions here

.github/ISSUE_TEMPLATE/feature-request.md

@@ -1,5 +1,5 @@
 ---
-name: Feature request
+name: Feature Request
 about: Create a proposal to request a feature
 
 ---
@@ -25,3 +25,12 @@ Are there any disadvantages of including this feature? -->
 ## Proposal
 
 <!-- Detailed description of requirements of implementation -->
+
+____
+
+#### For Admin Use
+
+- [ ] Not duplicate issue
+- [ ] Appropriate labels applied
+- [ ] Appropriate contributors tagged
+- [ ] Contributor assigned/self-assigned

.github/ISSUE_TEMPLATE/proposal.md

@@ -1,5 +1,5 @@
 ---
-name: Protocol change proposal
+name: Protocol Change Proposal
 about: Create a proposal to request a change to the protocol
 
 ---
@@ -26,3 +26,12 @@ Are there any disadvantages of including this change? -->
 ## Proposal
 
 <!-- Detailed description of requirements of implementation -->
+
+____
+
+#### For Admin Use
+
+- [ ] Not duplicate issue
+- [ ] Appropriate labels applied
+- [ ] Appropriate contributors tagged
+- [ ] Contributor assigned/self-assigned

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,32 +1,7 @@
-<!--
+## Description
 
-Please add a reference to the issue that this PR addresses and indicate which
-files are most critical to review. If it fully addresses a particular issue,
-please include "Closes #XXX" (where "XXX" is the issue number).
+_Please add a description of the changes that this PR introduces and the files that
+are the most critical to review._ 
 
-If this PR is non-trivial/large/complex, please ensure that you have either
-created an issue that the team's had a chance to respond to, or had some
-discussion with the team prior to submitting substantial pull requests. The team
-can be reached via GitHub Discussions or the Cosmos Network Discord server in
-the #tendermint-core channel. GitHub Discussions is preferred over Discord as it
-allows us to keep track of conversations topically.
-https://github.com/tendermint/tendermint/discussions
-
-If the work in this PR is not aligned with the team's current priorities, please
-be advised that it may take some time before it is merged - especially if it has
-not yet been discussed with the team.
-
-See the project board for the team's current priorities:
-https://github.com/orgs/tendermint/projects/15/views/5
-
--->
-
----
-
-#### PR checklist
-
-- [ ] Tests written/updated, or no tests needed
-- [ ] `CHANGELOG_PENDING.md` updated, or no changelog entry needed
-- [ ] Updated relevant documentation (`docs/`) and code comments, or no
-      documentation updates needed
+Closes: #XXX
 

.github/auto-comment.yml

@@ -0,0 +1,16 @@
+pullRequestOpened: |
+  :wave: Thanks for creating a PR!   
+
+  Before we can merge this PR, please make sure that all the following items have been 
+  checked off. If any of the checklist items are not applicable, please leave them but
+  write a little note why.   
+
+  - [ ] Wrote tests  
+  - [ ] Updated CHANGELOG_PENDING.md   
+  - [ ] Linked to Github issue with discussion and accepted design OR link to spec that describes this work.  
+  - [ ] Updated relevant documentation (`docs/`) and code comments  
+  - [ ] Re-reviewed `Files changed` in the Github PR explorer  
+  - [ ] Applied Appropriate Labels  
+
+
+  Thank you for your contribution to Tendermint! :rocket:   

.github/codecov.yml

@@ -1,25 +0,0 @@
-coverage:
-  precision: 2
-  round: down
-  range: "70...100"
-  status:
-    project:
-      default:
-        threshold: 20%
-    patch: off
-    changes: off
-
-github_checks:
-  annotations: false
-
-comment: false
-
-ignore:
-  - "docs"
-  - "DOCKER"
-  - "scripts"
-  - "**/*.pb.go"
-  - "libs/pubsub/query/query.peg.go"
-  - "*.md"
-  - "*.rst"
-  - "*.yml"

.github/dependabot.yml

@@ -1,51 +0,0 @@
-version: 2
-updates:
-  - package-ecosystem: github-actions
-    directory: "/"
-    schedule:
-      interval: weekly
-    target-branch: "main"
-    open-pull-requests-limit: 10
-    labels:
-      - T:dependencies
-      - S:automerge
-
-  - package-ecosystem: github-actions
-    directory: "/"
-    schedule:
-      interval: weekly
-    target-branch: "v0.34.x"
-    open-pull-requests-limit: 10
-    labels:
-      - T:dependencies
-      - S:automerge
-
-  - package-ecosystem: npm
-    directory: "/docs"
-    schedule:
-      interval: weekly
-    open-pull-requests-limit: 10
-
-  ###################################
-  ##
-  ## Update All Go Dependencies
-
-  - package-ecosystem: gomod
-    directory: "/"
-    schedule:
-      interval: weekly
-    target-branch: "main"
-    open-pull-requests-limit: 10
-    labels:
-      - T:dependencies
-      - S:automerge
-
-  - package-ecosystem: gomod
-    directory: "/"
-    schedule:
-      interval: weekly
-    target-branch: "v0.34.x"
-    open-pull-requests-limit: 10
-    labels:
-      - T:dependencies
-      - S:automerge

.github/issue_template.md

@@ -1,6 +0,0 @@
-<!--
-
-If you want to ask a general question, please create a new discussion instead of
-an issue: https://github.com/tendermint/tendermint/discussions
-
--->

.github/linters/markdownlint.yml

@@ -1,15 +0,0 @@
-# markdownlint configuration for Super-Linter
-# - https://github.com/DavidAnson/markdownlint
-# - https://github.com/github/super-linter
-
-# Default state for all rules
-default: true
-
-# See https://github.com/DavidAnson/markdownlint#rules--aliases for rules
-MD007: {"indent": 4}
-MD013: false
-MD024: {siblings_only: true}
-MD025: false
-MD033: {no-inline-html: false}
-no-hard-tabs: false
-whitespace: false

.github/linters/yaml-lint.yml

@@ -1,9 +0,0 @@
----
-# Default rules for YAML linting from super-linter.
-# See: See https://yamllint.readthedocs.io/en/stable/rules.html
-extends: default
-rules:
-  document-end: disable
-  document-start: disable
-  line-length: disable
-  truthy: disable

.github/mergify.yml

@@ -1,13 +1,13 @@
 queue_rules:
   - name: default
     conditions:
-      - base=main
+      - base=v0.34.x
       - label=S:automerge
 
 pull_request_rules:
-  - name: Automerge to main
+  - name: Automerge to v0.34.x
     conditions:
-      - base=main
+      - base=v0.34.x
       - label=S:automerge
     actions:
       queue:
@@ -17,11 +17,3 @@ pull_request_rules:
           {{ title }} (#{{ number }})
 
           {{ body }}
-  - name: backport patches to v0.34.x branch
-    conditions:
-      - base=main
-      - label=S:backport-to-v0.34.x
-    actions:
-      backport:
-        branches:
-          - v0.34.x

.github/workflows/build.yml

@@ -1,82 +0,0 @@
-name: Build
-# Tests runs different tests (test_abci_apps, test_abci_cli, test_apps)
-# This workflow runs on every push to main or release branch and  every pull requests
-# All jobs will pass without running if no *{.go, .mod, .sum} files have been modified
-on:
-  pull_request:
-  push:
-    branches:
-      - main
-      - release/**
-
-jobs:
-  build:
-    name: Build
-    runs-on: ubuntu-latest
-    strategy:
-      fail-fast: false
-      matrix:
-        goarch: ["arm", "amd64"]
-        goos: ["linux"]
-    timeout-minutes: 5
-    steps:
-      - uses: actions/setup-go@v3
-        with:
-          go-version: "1.18"
-      - uses: actions/checkout@v3
-      - uses: technote-space/get-diff-action@v6
-        with:
-          PATTERNS: |
-            **/*.go
-            "!test/"
-            go.mod
-            go.sum
-            Makefile
-      - name: install
-        run: GOOS=${{ matrix.goos }} GOARCH=${{ matrix.goarch }} make build
-        if: "env.GIT_DIFF != ''"
-
-  test_abci_cli:
-    runs-on: ubuntu-latest
-    needs: build
-    timeout-minutes: 5
-    steps:
-      - uses: actions/setup-go@v3
-        with:
-          go-version: "1.18"
-      - uses: actions/checkout@v3
-      - uses: technote-space/get-diff-action@v6
-        with:
-          PATTERNS: |
-            **/*.go
-            go.mod
-            go.sum
-      - name: install
-        run: make install_abci
-        if: "env.GIT_DIFF != ''"
-      - run: abci/tests/test_cli/test.sh
-        shell: bash
-        if: "env.GIT_DIFF != ''"
-
-  test_apps:
-    runs-on: ubuntu-latest
-    needs: build
-    timeout-minutes: 5
-    steps:
-      - uses: actions/setup-go@v3
-        with:
-          go-version: "1.18"
-      - uses: actions/checkout@v3
-      - uses: technote-space/get-diff-action@v6
-        with:
-          PATTERNS: |
-            **/*.go
-            go.mod
-            go.sum
-      - name: install
-        run: make install install_abci
-        if: "env.GIT_DIFF != ''"
-      - name: test_apps
-        run: test/app/test.sh
-        shell: bash
-        if: "env.GIT_DIFF != ''"

.github/workflows/coverage.yml

@@ -0,0 +1,123 @@
+name: Test Coverage
+on:
+  pull_request:
+  push:
+    branches:
+      - master
+      - release/**
+
+jobs:
+  split-test-files:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: Create a file with all the pkgs
+        run: go list ./... > pkgs.txt
+      - name: Split pkgs into 4 files
+        run: split -d -n l/4 pkgs.txt pkgs.txt.part.
+      # cache multiple
+      - uses: actions/upload-artifact@v3
+        with:
+          name: "${{ github.sha }}-00"
+          path: ./pkgs.txt.part.00
+      - uses: actions/upload-artifact@v3
+        with:
+          name: "${{ github.sha }}-01"
+          path: ./pkgs.txt.part.01
+      - uses: actions/upload-artifact@v3
+        with:
+          name: "${{ github.sha }}-02"
+          path: ./pkgs.txt.part.02
+      - uses: actions/upload-artifact@v3
+        with:
+          name: "${{ github.sha }}-03"
+          path: ./pkgs.txt.part.03
+
+  build-linux:
+    name: Build
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        goarch: ["arm", "amd64"]
+    timeout-minutes: 5
+    steps:
+      - uses: actions/setup-go@v3
+        with:
+          go-version: "1.18"
+      - uses: actions/checkout@v3
+      - uses: technote-space/get-diff-action@v6
+        with:
+          PATTERNS: |
+            **/**.go
+            go.mod
+            go.sum
+      - name: install
+        run: GOOS=linux GOARCH=${{ matrix.goarch }} make build
+        if: "env.GIT_DIFF != ''"
+
+  tests:
+    runs-on: ubuntu-latest
+    needs: split-test-files
+    strategy:
+      fail-fast: false
+      matrix:
+        part: ["00", "01", "02", "03"]
+    steps:
+      - uses: actions/setup-go@v3
+        with:
+          go-version: "1.18"
+      - uses: actions/checkout@v3
+      - uses: technote-space/get-diff-action@v6
+        with:
+          PATTERNS: |
+            **/**.go
+            go.mod
+            go.sum
+      - uses: actions/download-artifact@v3
+        with:
+          name: "${{ github.sha }}-${{ matrix.part }}"
+        if: env.GIT_DIFF
+      - name: test & coverage report creation
+        run: |
+          cat pkgs.txt.part.${{ matrix.part }} | xargs go test -mod=readonly -timeout 8m -race -coverprofile=${{ matrix.part }}profile.out -covermode=atomic
+        if: env.GIT_DIFF
+      - uses: actions/upload-artifact@v3
+        with:
+          name: "${{ github.sha }}-${{ matrix.part }}-coverage"
+          path: ./${{ matrix.part }}profile.out
+
+  upload-coverage-report:
+    runs-on: ubuntu-latest
+    needs: tests
+    steps:
+      - uses: actions/checkout@v3
+      - uses: technote-space/get-diff-action@v6
+        with:
+          PATTERNS: |
+            **/**.go
+            go.mod
+            go.sum
+      - uses: actions/download-artifact@v3
+        with:
+          name: "${{ github.sha }}-00-coverage"
+        if: env.GIT_DIFF
+      - uses: actions/download-artifact@v3
+        with:
+          name: "${{ github.sha }}-01-coverage"
+        if: env.GIT_DIFF
+      - uses: actions/download-artifact@v3
+        with:
+          name: "${{ github.sha }}-02-coverage"
+        if: env.GIT_DIFF
+      - uses: actions/download-artifact@v3
+        with:
+          name: "${{ github.sha }}-03-coverage"
+        if: env.GIT_DIFF
+      - run: |
+          cat ./*profile.out | grep -v "mode: atomic" >> coverage.txt
+        if: env.GIT_DIFF
+      - uses: codecov/codecov-action@v3
+        with:
+          file: ./coverage.txt
+        if: env.GIT_DIFF

.github/workflows/docker.yml

@@ -1,13 +1,14 @@
-name: Docker
-# Build & Push rebuilds the Tendermint docker image on every push to main and creation of tags
-# and pushes the image to https://hub.docker.com/r/tendermint/tendermint
+name: Build & Push
+#  Build & Push rebuilds the tendermint docker image on every push to master and creation of tags
+# and pushes the image to https://hub.docker.com/r/interchainio/simapp/tags
 on:
+  pull_request:
   push:
     branches:
-      - main
+      - master
     tags:
-      - "v[0-9]+.[0-9]+.[0-9]+"  # Push events to matching v*, i.e. v1.0, v20.15.10
-      - "v[0-9]+.[0-9]+.[0-9]+-rc*"  # Push events to matching v*, i.e. v1.0-rc1, v20.15.10-rc5
+      - "v[0-9]+.[0-9]+.[0-9]+" # Push events to matching v*, i.e. v1.0, v20.15.10
+      - "v[0-9]+.[0-9]+.[0-9]+-rc*" # Push events to matching v*, i.e. v1.0-rc1, v20.15.10-rc5
 
 jobs:
   build:
@@ -38,18 +39,18 @@ jobs:
         with:
           platforms: all
 
-      - name: Set up Docker Build
-        uses: docker/setup-buildx-action@v2.0.0
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v2
 
       - name: Login to DockerHub
         if: ${{ github.event_name != 'pull_request' }}
-        uses: docker/login-action@v2.0.0
+        uses: docker/login-action@v2
         with:
           username: ${{ secrets.DOCKERHUB_USERNAME }}
           password: ${{ secrets.DOCKERHUB_TOKEN }}
 
       - name: Publish to Docker Hub
-        uses: docker/build-push-action@v3.1.1
+        uses: docker/build-push-action@v3
         with:
           context: .
           file: ./DOCKER/Dockerfile

.github/workflows/docs-deployment.yml

@@ -1,62 +0,0 @@
-# Build and deploy the docs.tendermint.com website content.
-# The static content is published to GitHub Pages.
-#
-# For documentation build info, see docs/DOCS_README.md.
-name: Build static documentation site
-on:
-  workflow_dispatch:  # allow manual updates
-  push:
-    branches:
-      - main
-    paths:
-      - docs/**
-      - spec/**
-
-jobs:
-  # This is split into two jobs so that the build, which runs npm, does not
-  # have write access to anything. The deploy requires write access to publish
-  # to the branch used by GitHub Pages, however, so we can't just make the
-  # whole workflow read-only.
-  build:
-    name: VuePress build
-    runs-on: ubuntu-latest
-    container:
-      image: alpine:latest
-    permissions:
-      contents: read
-    steps:
-      - name: Install generator dependencies
-        run: |
-          apk add --no-cache make bash git npm
-      - uses: actions/checkout@v3
-        with:
-          # We need to fetch full history so the backport branches for previous
-          # versions will be available for the build.
-          fetch-depth: 0
-      - name: Build documentation
-        run: |
-          git config --global --add safe.directory "$PWD"
-          make build-docs
-      - uses: actions/upload-artifact@v3
-        with:
-          name: build-output
-          path: ~/output/
-
-  deploy:
-    name: Deploy to GitHub Pages
-    runs-on: ubuntu-latest
-    needs: build
-    permissions:
-      contents: write
-    steps:
-      - uses: actions/checkout@v3
-      - uses: actions/download-artifact@v3
-        with:
-          name: build-output
-          path: ~/output
-      - name: Deploy to GitHub Pages
-        uses: JamesIves/github-pages-deploy-action@v4
-        with:
-          branch: 'docs-tendermint-com'
-          folder: ~/output
-          single-commit: true

.github/workflows/docs-toc.yml

@@ -1,20 +0,0 @@
-# Verify that important design docs have ToC entries.
-name: Check documentation ToC
-on:
-  pull_request:
-    push:
-      branches:
-        - main
-
-jobs:
-  check:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v3
-      - uses: technote-space/get-diff-action@v6
-        with:
-          PATTERNS: |
-            docs/architecture/**
-            docs/rfc/**
-      - run: make check-docs-toc
-        if: env.GIT_DIFF

.github/workflows/e2e-manual.yml

@@ -1,5 +1,4 @@
-# Runs randomly generated E2E testnets nightly on main
-# manually run e2e tests
+# Manually run randomly generated E2E testnets (as nightly).
 name: e2e-manual
 on:
   workflow_dispatch:
@@ -29,7 +28,7 @@ jobs:
       - name: Generate testnets
         working-directory: test/e2e
         # When changing -g, also change the matrix groups above
-        run: ./build/generator -g 5 -d networks/nightly/
+        run: ./build/generator -g 4 -d networks/nightly/
 
       - name: Run ${{ matrix.p2p }} p2p testnets
         working-directory: test/e2e

.github/workflows/e2e-nightly-34x.yml

@@ -1,10 +1,12 @@
-# Runs randomly generated E2E testnets nightly on the 0.34.x branch.
+# Runs randomly generated E2E testnets nightly
+# on the 0.34.x release branch
 
-# !! This file should be kept in sync with the e2e-nightly-main.yml file,
-# modulo changes to the version labels.
+# !! If you change something in this file, you probably want
+# to update the e2e-nightly-master workflow as well!
 
 name: e2e-nightly-34x
 on:
+  workflow_dispatch: # allow running workflow manually, in theory
   schedule:
     - cron: '0 2 * * *'
 
@@ -15,7 +17,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        group: ['00', '01', '02', '03', "04"]
+        group: ['00', '01', '02', '03']
     runs-on: ubuntu-latest
     timeout-minutes: 60
     steps:
@@ -27,12 +29,6 @@ jobs:
         with:
           ref: 'v0.34.x'
 
-      - name: Capture git repo info
-        id: git-info
-        run: |
-          echo "::set-output name=branch::`git branch --show-current`"
-          echo "::set-output name=commit::`git rev-parse HEAD`"
-
       - name: Build
         working-directory: test/e2e
         # Run make jobs in parallel, since we can't run steps in parallel.
@@ -41,64 +37,40 @@ jobs:
       - name: Generate testnets
         working-directory: test/e2e
         # When changing -g, also change the matrix groups above
-        run: ./build/generator -g 2 -d networks/nightly
+        run: ./build/generator -g 4 -d networks/nightly
 
       - name: Run testnets in group ${{ matrix.group }}
         working-directory: test/e2e
         run: ./run-multiple.sh networks/nightly/*-group${{ matrix.group }}-*.toml
 
-    outputs:
-      git-branch: ${{ steps.git-info.outputs.branch }}
-      git-commit: ${{ steps.git-info.outputs.commit }}
-
   e2e-nightly-fail:
     needs: e2e-nightly-test
     if: ${{ failure() }}
     runs-on: ubuntu-latest
     steps:
       - name: Notify Slack on failure
-        uses: slackapi/slack-github-action@v1.21.0
+        uses: rtCamp/action-slack-notify@f565a63638bd3615e76249bffab00fcb9dab90f7
         env:
-          SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
-          SLACK_WEBHOOK_TYPE: INCOMING_WEBHOOK
-          BRANCH: ${{ needs.e2e-nightly-test.outputs.git-branch }}
-          RUN_URL: "${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}"
-          COMMIT_URL: "${{ github.server_url }}/${{ github.repository }}/commit/${{ needs.e2e-nightly-test.outputs.git-commit }}"
-        with:
-          payload: |
-            {
-              "blocks": [
-                {
-                  "type": "section",
-                  "text": {
-                    "type": "mrkdwn",
-                    "text": ":skull: Nightly E2E tests for `${{ env.BRANCH }}` failed. See the <${{ env.RUN_URL }}|run details> and the <${{ env.COMMIT_URL }}|commit> that caused the failure."
-                  }
-                }
-              ]
-            }
+          SLACK_WEBHOOK: ${{ secrets.SLACK_WEBHOOK }}
+          SLACK_CHANNEL: tendermint-internal
+          SLACK_USERNAME: Nightly E2E Tests
+          SLACK_ICON_EMOJI: ':skull:'
+          SLACK_COLOR: danger
+          SLACK_MESSAGE: Nightly E2E tests failed on v0.34.x
+          SLACK_FOOTER: ''
 
-  e2e-nightly-success:  # may turn this off once they seem to pass consistently
+  e2e-nightly-success: # may turn this off once they seem to pass consistently
     needs: e2e-nightly-test
     if: ${{ success() }}
     runs-on: ubuntu-latest
     steps:
       - name: Notify Slack on success
-        uses: slackapi/slack-github-action@v1.21.0
+        uses: rtCamp/action-slack-notify@f565a63638bd3615e76249bffab00fcb9dab90f7
         env:
-          SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
-          SLACK_WEBHOOK_TYPE: INCOMING_WEBHOOK
-          BRANCH: ${{ needs.e2e-nightly-test.outputs.git-branch }}
-        with:
-          payload: |
-            {
-              "blocks": [
-                {
-                  "type": "section",
-                  "text": {
-                    "type": "mrkdwn",
-                    "text": ":white_check_mark: Nightly E2E tests for `${{ env.BRANCH }}` passed."
-                  }
-                }
-              ]
-            }
+          SLACK_WEBHOOK: ${{ secrets.SLACK_WEBHOOK }}
+          SLACK_CHANNEL: tendermint-internal
+          SLACK_USERNAME: Nightly E2E Tests
+          SLACK_ICON_EMOJI: ':white_check_mark:'
+          SLACK_COLOR: good
+          SLACK_MESSAGE: Nightly E2E tests passed on v0.34.x
+          SLACK_FOOTER: ''

.github/workflows/e2e-nightly-main.yml

@@ -1,93 +0,0 @@
-# Runs randomly generated E2E testnets nightly on main
-
-# !! Relevant changes to this file should be propagated to the e2e-nightly-<V>x
-# files for the supported backport branches, when appropriate, modulo version
-# markers.
-
-name: e2e-nightly-main
-on:
-  schedule:
-    - cron: '0 2 * * *'
-
-jobs:
-  e2e-nightly-test:
-    # Run parallel jobs for the listed testnet groups (must match the
-    # ./build/generator -g flag)
-    strategy:
-      fail-fast: false
-      matrix:
-        group: ['00', '01', '02', '03', "04"]
-    runs-on: ubuntu-latest
-    timeout-minutes: 60
-    steps:
-      - uses: actions/setup-go@v3
-        with:
-          go-version: '1.18'
-
-      - uses: actions/checkout@v3
-
-      - name: Build
-        working-directory: test/e2e
-        # Run make jobs in parallel, since we can't run steps in parallel.
-        run: make -j2 docker generator runner tests
-
-      - name: Generate testnets
-        working-directory: test/e2e
-        # When changing -g, also change the matrix groups above
-        run: ./build/generator -g 5 -d networks/nightly/
-
-      - name: Run ${{ matrix.p2p }} p2p testnets
-        working-directory: test/e2e
-        run: ./run-multiple.sh networks/nightly/*-group${{ matrix.group }}-*.toml
-
-  e2e-nightly-fail:
-    needs: e2e-nightly-test
-    if: ${{ failure() }}
-    runs-on: ubuntu-latest
-    steps:
-      - name: Notify Slack on failure
-        uses: slackapi/slack-github-action@v1.21.0
-        env:
-          SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
-          SLACK_WEBHOOK_TYPE: INCOMING_WEBHOOK
-          BRANCH: ${{ github.ref_name }}
-          RUN_URL: "${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}"
-          COMMIT_URL: "${{ github.server_url }}/${{ github.repository }}/commit/${{ github.sha }}"
-        with:
-          payload: |
-            {
-              "blocks": [
-                {
-                  "type": "section",
-                  "text": {
-                    "type": "mrkdwn",
-                    "text": ":skull: Nightly E2E tests for `${{ env.BRANCH }}` failed. See the <${{ env.RUN_URL }}|run details> and the <${{ env.COMMIT_URL }}|commit> that caused the failure."
-                  }
-                }
-              ]
-            }
-
-  e2e-nightly-success:  # may turn this off once they seem to pass consistently
-    needs: e2e-nightly-test
-    if: ${{ success() }}
-    runs-on: ubuntu-latest
-    steps:
-      - name: Notify Slack on success
-        uses: slackapi/slack-github-action@v1.21.0
-        env:
-          SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
-          SLACK_WEBHOOK_TYPE: INCOMING_WEBHOOK
-          BRANCH: ${{ github.ref_name }}
-        with:
-          payload: |
-            {
-              "blocks": [
-                {
-                  "type": "section",
-                  "text": {
-                    "type": "mrkdwn",
-                    "text": ":white_check_mark: Nightly E2E tests for `${{ env.BRANCH }}` passed."
-                  }
-                }
-              ]
-            }

.github/workflows/e2e-nightly-master.yml

@@ -0,0 +1,73 @@
+# Runs randomly generated E2E testnets nightly on master
+
+# !! If you change something in this file, you probably want
+# to update the e2e-nightly-34x workflow as well!
+
+name: e2e-nightly-master
+on:
+  workflow_dispatch: # allow running workflow manually
+  schedule:
+    - cron: '0 2 * * *'
+
+jobs:
+  e2e-nightly-test-2:
+    # Run parallel jobs for the listed testnet groups (must match the
+    # ./build/generator -g flag)
+    strategy:
+      fail-fast: false
+      matrix:
+        group: ['00', '01', '02', '03']
+    runs-on: ubuntu-latest
+    timeout-minutes: 60
+    steps:
+      - uses: actions/setup-go@v3
+        with:
+          go-version: '1.18'
+
+      - uses: actions/checkout@v3
+
+      - name: Build
+        working-directory: test/e2e
+        # Run make jobs in parallel, since we can't run steps in parallel.
+        run: make -j2 docker generator runner
+
+      - name: Generate testnets
+        working-directory: test/e2e
+        # When changing -g, also change the matrix groups above
+        run: ./build/generator -g 4 -d networks/nightly
+
+      - name: Run testnets in group ${{ matrix.group }}
+        working-directory: test/e2e
+        run: ./run-multiple.sh networks/nightly/*-group${{ matrix.group }}-*.toml
+
+  e2e-nightly-fail-2:
+    needs: e2e-nightly-test-2
+    if: ${{ failure() }}
+    runs-on: ubuntu-latest
+    steps:
+      - name: Notify Slack on failure
+        uses: rtCamp/action-slack-notify@f565a63638bd3615e76249bffab00fcb9dab90f7
+        env:
+          SLACK_WEBHOOK: ${{ secrets.SLACK_WEBHOOK }}
+          SLACK_CHANNEL: tendermint-internal
+          SLACK_USERNAME: Nightly E2E Tests
+          SLACK_ICON_EMOJI: ':skull:'
+          SLACK_COLOR: danger
+          SLACK_MESSAGE: Nightly E2E tests failed on master
+          SLACK_FOOTER: ''
+
+  e2e-nightly-success: # may turn this off once they seem to pass consistently
+    needs: e2e-nightly-test-2
+    if: ${{ success() }}
+    runs-on: ubuntu-latest
+    steps:
+      - name: Notify Slack on success
+        uses: rtCamp/action-slack-notify@f565a63638bd3615e76249bffab00fcb9dab90f7
+        env:
+          SLACK_WEBHOOK: ${{ secrets.SLACK_WEBHOOK }}
+          SLACK_CHANNEL: tendermint-internal
+          SLACK_USERNAME: Nightly E2E Tests
+          SLACK_ICON_EMOJI: ':white_check_mark:'
+          SLACK_COLOR: good
+          SLACK_MESSAGE: Nightly E2E tests passed on master
+          SLACK_FOOTER: ''

.github/workflows/e2e.yml

@@ -1,12 +1,11 @@
 name: e2e
-# Runs the CI end-to-end test network on all pushes to main or release branches
+# Runs the CI end-to-end test network on all pushes to master or release branches
 # and every pull request, but only if any Go files have been changed.
 on:
-  workflow_dispatch:  # allow running workflow manually
   pull_request:
   push:
     branches:
-      - main
+      - master
       - release/**
 
 jobs:
@@ -28,10 +27,15 @@ jobs:
       - name: Build
         working-directory: test/e2e
         # Run two make jobs in parallel, since we can't run steps in parallel.
-        run: make -j2 docker runner tests
+        run: make -j2 docker runner
         if: "env.GIT_DIFF != ''"
 
       - name: Run CI testnet
         working-directory: test/e2e
-        run: ./run-multiple.sh networks/ci.toml
+        run: ./build/runner -f networks/ci.toml
         if: "env.GIT_DIFF != ''"
+
+      - name: Emit logs on failure
+        if: ${{ failure() }}
+        working-directory: test/e2e
+        run: ./build/runner -f networks/ci.toml logs

.github/workflows/fuzz-nightly.yml

@@ -1,13 +1,9 @@
 # Runs fuzzing nightly.
-name: Fuzz Tests
+name: fuzz-nightly
 on:
-  workflow_dispatch:  # allow running workflow manually
+  workflow_dispatch: # allow running workflow manually
   schedule:
     - cron: '0 3 * * *'
-  pull_request:
-    branches: [main]
-    paths:
-      - "test/fuzz/**/*.go"
 
 jobs:
   fuzz-nightly-test:
@@ -21,7 +17,7 @@ jobs:
 
       - name: Install go-fuzz
         working-directory: test/fuzz
-        run: go install github.com/dvyukov/go-fuzz/go-fuzz@latest github.com/dvyukov/go-fuzz/go-fuzz-build@latest
+        run: go get -u github.com/dvyukov/go-fuzz/go-fuzz github.com/dvyukov/go-fuzz/go-fuzz-build
 
       - name: Fuzz mempool
         working-directory: test/fuzz
@@ -53,14 +49,14 @@ jobs:
         with:
           name: crashers
           path: test/fuzz/**/crashers
-          retention-days: 3
+          retention-days: 1
 
       - name: Archive suppressions
         uses: actions/upload-artifact@v3
         with:
           name: suppressions
           path: test/fuzz/**/suppressions
-          retention-days: 3
+          retention-days: 1
 
       - name: Set crashers count
         working-directory: test/fuzz
@@ -75,24 +71,13 @@ jobs:
     if: ${{ needs.fuzz-nightly-test.outputs.crashers-count != 0 }}
     runs-on: ubuntu-latest
     steps:
-      - name: Notify Slack on failure
-        uses: slackapi/slack-github-action@v1.21.0
+      - name: Notify Slack if any crashers
+        uses: rtCamp/action-slack-notify@f565a63638bd3615e76249bffab00fcb9dab90f7
         env:
-          SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
-          SLACK_WEBHOOK_TYPE: INCOMING_WEBHOOK
-          BRANCH: ${{ github.ref_name }}
-          CRASHERS: ${{ needs.fuzz-nightly-test.outputs.crashers-count }}
-          RUN_URL: "${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}"
-        with:
-          payload: |
-            {
-              "blocks": [
-                {
-                  "type": "section",
-                  "text": {
-                    "type": "mrkdwn",
-                    "text": ":skull: Nightly fuzz tests for `${{ env.BRANCH }}` failed with ${{ env.CRASHERS }} crasher(s). See the <${{ env.RUN_URL }}|run details>."
-                  }
-                }
-              ]
-            }
+          SLACK_WEBHOOK: ${{ secrets.SLACK_WEBHOOK }}
+          SLACK_CHANNEL: tendermint-internal
+          SLACK_USERNAME: Nightly Fuzz Tests
+          SLACK_ICON_EMOJI: ':firecracker:'
+          SLACK_COLOR: danger
+          SLACK_MESSAGE: Crashers found in Nightly Fuzz tests
+          SLACK_FOOTER: ''

.github/workflows/janitor.yml

@@ -1,16 +0,0 @@
-name: Janitor
-# Janitor cleans up previous runs of various workflows
-# To add more workflows to cancel visit https://api.github.com/repos/tendermint/tendermint/actions/workflows and find the actions name
-on:
-  pull_request:
-
-jobs:
-  cancel:
-    name: "Cancel Previous Runs"
-    runs-on: ubuntu-latest
-    timeout-minutes: 3
-    steps:
-      - uses: styfle/cancel-workflow-action@0.10.0
-        with:
-          workflow_id: 1041851,1401230,2837803
-          access_token: ${{ github.token }}

.github/workflows/lint.yml

@@ -1,18 +1,12 @@
-name: Golang Linter
-# Lint runs golangci-lint over the entire Tendermint repository.
-#
-# This workflow is run on every pull request and push to main.
-#
-# The `golangci` job will pass without running if no *.{go, mod, sum}
-# files have been modified.
-#
-# To run this locally, simply run `make lint` from the root of the repo.
-
+name: Lint
+# Lint runs golangci-lint over the entire Tendermint repository
+# This workflow is run on every pull request and push to master
+# The `golangci` job will pass without running if no *.{go, mod, sum} files have been modified.
 on:
   pull_request:
   push:
     branches:
-      - main
+      - master
 jobs:
   golangci:
     name: golangci-lint
@@ -34,7 +28,7 @@ jobs:
           # Required: the version of golangci-lint is required and
           # must be specified without patch version: we always use the
           # latest patch version.
-          version: v1.47.3
+          version: v1.50.1
           args: --timeout 10m
           github-token: ${{ secrets.github_token }}
         if: env.GIT_DIFF

.github/workflows/linter.yml

@@ -1,14 +1,14 @@
-name: Markdown Linter
+name: Lint
 on:
   push:
     branches:
-      - main
+      - master
     paths:
       - "**.md"
       - "**.yml"
       - "**.yaml"
   pull_request:
-    branches: [main]
+    branches: [master]
     paths:
       - "**.md"
       - "**.yml"
@@ -21,12 +21,12 @@ jobs:
       - name: Checkout Code
         uses: actions/checkout@v3
       - name: Lint Code Base
-        uses: docker://github/super-linter:v4
+        uses: docker://github/super-linter:v3
         env:
+          LINTER_RULES_PATH: .
           VALIDATE_ALL_CODEBASE: true
-          DEFAULT_BRANCH: main
+          DEFAULT_BRANCH: master
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           VALIDATE_MD: true
           VALIDATE_OPENAPI: true
           VALIDATE_YAML: true
-          YAML_CONFIG_FILE: yaml-lint.yml

.github/workflows/markdown-links.yml

@@ -1,23 +0,0 @@
-name: Check Markdown links
-
-on:
-  push:
-    branches:
-      - main
-  pull_request:
-    branches: [main]
-
-jobs:
-  markdown-link-check:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v3
-      - uses: technote-space/get-diff-action@v6
-        with:
-          PATTERNS: |
-            **/**.md
-      - uses: creachadair/github-action-markdown-link-check@master
-        with:
-          check-modified-files-only: 'yes'
-          config-file: '.md-link-check.json'
-        if: env.GIT_DIFF

.github/workflows/pre-release.yml

@@ -0,0 +1,65 @@
+name: "Pre-release"
+
+on:
+  push:
+    tags:
+      - "v[0-9]+.[0-9]+.[0-9]+-alpha.[0-9]+"  # e.g. v0.37.0-alpha.1, v0.38.0-alpha.10
+      - "v[0-9]+.[0-9]+.[0-9]+-beta.[0-9]+"   # e.g. v0.37.0-beta.1, v0.38.0-beta.10
+      - "v[0-9]+.[0-9]+.[0-9]+-rc[0-9]+"      # e.g. v0.37.0-rc1, v0.38.0-rc10
+
+jobs:
+  prerelease:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+
+      - uses: actions/setup-go@v3
+        with:
+          go-version: '1.18'
+
+      - name: Build
+        uses: goreleaser/goreleaser-action@v3
+        if: ${{ github.event_name == 'pull_request' }}
+        with:
+          version: latest
+          args: build --skip-validate   # skip validate skips initial sanity checks in order to be able to fully run
+
+      # Link to CHANGELOG_PENDING.md as release notes.
+      - run: echo https://github.com/tendermint/tendermint/blob/${GITHUB_REF#refs/tags/}/CHANGELOG_PENDING.md > ../release_notes.md
+
+      - name: Release
+        uses: goreleaser/goreleaser-action@v3
+        if: startsWith(github.ref, 'refs/tags/')
+        with:
+          version: latest
+          args: release --rm-dist --release-notes=../release_notes.md
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+  prerelease-success:
+    needs: prerelease
+    if: ${{ success() }}
+    runs-on: ubuntu-latest
+    steps:
+      - name: Notify Slack upon pre-release
+        uses: slackapi/slack-github-action@v1.23.0
+        env:
+          SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
+          SLACK_WEBHOOK_TYPE: INCOMING_WEBHOOK
+          RELEASE_URL: "${{ github.server_url }}/${{ github.repository }}/releases/tag/${{ github.ref_name }}"
+        with:
+          payload: |
+            {
+              "blocks": [
+                {
+                  "type": "section",
+                  "text": {
+                    "type": "mrkdwn",
+                    "text": ":sparkles: New Tendermint pre-release: <${{ env.RELEASE_URL }}|${{ github.ref_name }}>"
+                  }
+                }
+              ]
+            }

.github/workflows/proto-lint.yml

@@ -5,7 +5,7 @@ on:
       - 'proto/**'
   push:
     branches:
-      - main
+      - v0.34.x
     paths:
       - 'proto/**'
 
@@ -15,7 +15,7 @@ jobs:
     timeout-minutes: 5
     steps:
       - uses: actions/checkout@v3
-      - uses: bufbuild/buf-setup-action@v1.7.0
+      - uses: bufbuild/buf-setup-action@v1.8.0
       - uses: bufbuild/buf-lint-action@v1
         with:
           input: 'proto'

.github/workflows/release.yml

@@ -6,7 +6,7 @@ on:
       - "v[0-9]+.[0-9]+.[0-9]+"  # Push events to matching v*, i.e. v1.0, v20.15.10
 
 jobs:
-  goreleaser:
+  release:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
@@ -35,3 +35,28 @@ jobs:
           args: release --rm-dist --release-notes=../release_notes.md
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+  release-success:
+    needs: release
+    if: ${{ success() }}
+    runs-on: ubuntu-latest
+    steps:
+      - name: Notify Slack upon release
+        uses: slackapi/slack-github-action@v1.23.0
+        env:
+          SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
+          SLACK_WEBHOOK_TYPE: INCOMING_WEBHOOK
+          RELEASE_URL: "${{ github.server_url }}/${{ github.repository }}/releases/tag/${{ github.ref_name }}"
+        with:
+          payload: |
+            {
+              "blocks": [
+                {
+                  "type": "section",
+                  "text": {
+                    "type": "mrkdwn",
+                    "text": ":rocket: New Tendermint release: <${{ env.RELEASE_URL }}|${{ github.ref_name }}>"
+                  }
+                }
+              ]
+            }

.github/workflows/stale.yml

@@ -7,14 +7,12 @@ jobs:
   stale:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/stale@v5
+      - uses: actions/stale@v6
         with:
           repo-token: ${{ secrets.GITHUB_TOKEN }}
           stale-pr-message: "This pull request has been automatically marked as stale because it has not had
     recent activity. It will be closed if no further activity occurs. Thank you
     for your contributions."
-          days-before-stale: -1
-          days-before-close: -1
-          days-before-pr-stale: 10
-          days-before-pr-close: 4
+          days-before-stale: 10
+          days-before-close: 4
           exempt-pr-labels: "S:wip"

.github/workflows/tests.yml

@@ -1,20 +1,27 @@
-name: Test
+name: Tests
+# Tests runs different tests (test_abci_apps, test_abci_cli, test_apps)
+# This workflow runs on every push to master or release branch and  every pull requests
+# All jobs will pass without running if no *{.go, .mod, .sum} files have been modified
 on:
   pull_request:
   push:
-    paths:
-      - "**.go"
     branches:
-      - main
+      - master
       - release/**
 
 jobs:
-  tests:
+  cleanup-runs:
     runs-on: ubuntu-latest
-    strategy:
-      fail-fast: false
-      matrix:
-        part: ["00", "01", "02", "03", "04", "05"]
+    steps:
+      - uses: rokroskar/workflow-run-cleanup-action@master
+        env:
+          GITHUB_TOKEN: "${{ secrets.GITHUB_TOKEN }}"
+    if: "!startsWith(github.ref, 'refs/tags/') && github.ref != 'refs/heads/master'"
+
+  build:
+    name: Build
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
     steps:
       - uses: actions/setup-go@v3
         with:
@@ -24,11 +31,116 @@ jobs:
         with:
           PATTERNS: |
             **/**.go
-            "!test/"
             go.mod
             go.sum
-            Makefile
-      - name: Run Go Tests
-        run: |
-          make test-group-${{ matrix.part }} NUM_SPLIT=6
+      - name: install
+        run: make install install_abci
+        if: "env.GIT_DIFF != ''"
+      - uses: actions/cache@v3
+        with:
+          path: ~/go/pkg/mod
+          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+          restore-keys: |
+            ${{ runner.os }}-go-
+        if: env.GIT_DIFF
+      # Cache binaries for use by other jobs
+      - uses: actions/cache@v3
+        with:
+          path: ~/go/bin
+          key: ${{ runner.os }}-${{ github.sha }}-tm-binary
+        if: env.GIT_DIFF
+
+  test_abci_apps:
+    runs-on: ubuntu-latest
+    needs: build
+    timeout-minutes: 5
+    steps:
+      - uses: actions/setup-go@v3
+        with:
+          go-version: "^1.18"
+      - uses: actions/checkout@v3
+      - uses: technote-space/get-diff-action@v6
+        with:
+          PATTERNS: |
+            **/**.go
+            go.mod
+            go.sum
+      - uses: actions/cache@v3
+        with:
+          path: ~/go/pkg/mod
+          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+          restore-keys: |
+            ${{ runner.os }}-go-
+        if: env.GIT_DIFF
+      - uses: actions/cache@v3
+        with:
+          path: ~/go/bin
+          key: ${{ runner.os }}-${{ github.sha }}-tm-binary
+        if: env.GIT_DIFF
+      - name: test_abci_apps
+        run: abci/tests/test_app/test.sh
+        shell: bash
+        if: env.GIT_DIFF
+
+  test_abci_cli:
+    runs-on: ubuntu-latest
+    needs: build
+    timeout-minutes: 5
+    steps:
+      - uses: actions/setup-go@v3
+        with:
+          go-version: "^1.18"
+      - uses: actions/checkout@v3
+      - uses: technote-space/get-diff-action@v6
+        with:
+          PATTERNS: |
+            **/**.go
+            go.mod
+            go.sum
+      - uses: actions/cache@v3
+        with:
+          path: ~/go/pkg/mod
+          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+          restore-keys: |
+            ${{ runner.os }}-go-
+        if: env.GIT_DIFF
+      - uses: actions/cache@v3
+        with:
+          path: ~/go/bin
+          key: ${{ runner.os }}-${{ github.sha }}-tm-binary
+        if: env.GIT_DIFF
+      - run: abci/tests/test_cli/test.sh
+        shell: bash
+        if: env.GIT_DIFF
+
+  test_apps:
+    runs-on: ubuntu-latest
+    needs: build
+    timeout-minutes: 5
+    steps:
+      - uses: actions/setup-go@v3
+        with:
+          go-version: "1.18"
+      - uses: actions/checkout@v3
+      - uses: technote-space/get-diff-action@v6
+        with:
+          PATTERNS: |
+            **/**.go
+            go.mod
+            go.sum
+      - uses: actions/cache@v3
+        with:
+          path: ~/go/pkg/mod
+          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+          restore-keys: |
+            ${{ runner.os }}-go-
+        if: env.GIT_DIFF
+      - uses: actions/cache@v3
+        with:
+          path: ~/go/bin
+          key: ${{ runner.os }}-${{ github.sha }}-tm-binary
+        if: env.GIT_DIFF
+      - name: test_apps
+        run: test/app/test.sh
+        shell: bash
         if: env.GIT_DIFF

.gitignore

@@ -1,57 +1,69 @@
-*.bak
-*.iml
-*.log
-*.swo
 *.swp
-*/.glide
-*/vendor
-.DS_Store
+*.swo
 .bak
-.idea/
-.revision
-.tendermint
-.tendermint-lite
-.terraform
-.vagrant
-.vendor-new/
-.vscode/
-abci/abci-cli
-addrbook.json
-artifacts/*
+*.bak
+.DS_Store
 build/*
+rpc/test/.tendermint
+.tendermint
+remote_dump
+.revision
+vendor
+.vagrant
+test/e2e/build
+test/maverick/maverick
+test/e2e/networks/*/
+test/p2p/data/
+test/logs
 coverage.txt
-docs/.vuepress/dist
 docs/_build
 docs/dist
+docs/.vuepress/dist
+*.log
+abci-cli
 docs/node_modules/
-docs/spec
 docs/.vuepress/public/rpc
 index.html.md
-libs/pubsub/query/fuzz_test/output
-profile\.out
-remote_dump
-rpc/test/.tendermint
-scripts/cutWALUntil/cutWALUntil
+
 scripts/wal2json/wal2json
+scripts/cutWALUntil/cutWALUntil
+
+.idea/
+*.iml
+
+.vscode/
+
+libs/pubsub/query/fuzz_test/output
 shunit2
+
+.tendermint-lite
+addrbook.json
+
+*/vendor
+.vendor-new/
+*/.glide
+.terraform
 terraform.tfstate
 terraform.tfstate.backup
 terraform.tfstate.d
+profile\.out
 test/app/grpc_client
+test/loadtime/build
 test/e2e/build
 test/e2e/networks/*/
 test/logs
+test/maverick/maverick
 test/p2p/data/
 vendor
 test/fuzz/**/corpus
 test/fuzz/**/crashers
 test/fuzz/**/suppressions
 test/fuzz/**/*.zip
-proto/spec/**/*.pb.go
 *.aux
 *.bbl
 *.blg
-*.log
 *.pdf
 *.gz
 *.dvi
+# Python virtual environments
+.venv

.golangci.yml

@@ -2,7 +2,6 @@ linters:
   enable:
     - asciicheck
     - bodyclose
-    - deadcode
     - depguard
     - dogsled
     - dupl
@@ -26,7 +25,6 @@ linters:
     - typecheck
     - unconvert
     - unused
-    - varcheck
 
 issues:
   exclude-rules:
@@ -42,5 +40,7 @@ linters-settings:
     min-confidence: 0
   maligned:
     suggest-new: true
-  misspell:
-    locale: US
+
+run:
+  skip-files:
+    - libs/pubsub/query/query.peg.go

.goreleaser.yml

@@ -5,7 +5,7 @@ env:
   - GO111MODULE=on
 
 builds:
-  - id: "tendermint"
+  - id: "Tendermint"
     main: ./cmd/tendermint/main.go
     ldflags:
       - -s -w -X github.com/tendermint/tendermint/version.TMCoreSemVer={{ .Version }}
@@ -25,7 +25,8 @@ checksum:
   algorithm: sha256
 
 release:
-  name_template: "{{.Version}} (WARNING: BETA SOFTWARE)"
+  prerelease: auto
+  name_template: "{{.Version}}"
 
 archives:
   - files:

.markdownlint.yml

@@ -1,10 +1,4 @@
-# markdownlint configuration
-# https://github.com/DavidAnson/markdownlint
-
-# Default state for all rules
 default: true
-
-# See https://github.com/DavidAnson/markdownlint#rules--aliases for rules
 MD001: false
 MD007: {indent: 4}
 MD013: false

.md-link-check.json

@@ -1,6 +0,0 @@
-{
-    "retryOn429": true,
-    "retryCount": 5,
-    "fallbackRetryDelay": "30s",
-    "aliveStatusCodes": [200, 206, 503]
-}

.mergify.yml

@@ -0,0 +1,10 @@
+pull_request_rules:
+  - name: Automerge to master
+    conditions:
+      - base=master
+      - label=S:automerge
+    actions:
+      merge:
+        method: squash
+        strict: true
+        commit_message: title+body

.vscode/settings.json

@@ -0,0 +1,9 @@
+{
+  "protoc": {
+    "options": [
+      "--proto_path=${workspaceRoot}/proto",
+      "--proto_path=${workspaceRoot}/third_party/proto"
+    ]
+  }
+  
+}

CHANGELOG.md

@@ -2,6 +2,126 @@
 
 Friendly reminder, we have a [bug bounty program](https://hackerone.com/cosmos).
 
+## v0.34.24
+
+*Nov 21, 2022*
+
+Apart from one minor bug fix, this release aims to optimize the output of the
+RPC (both HTTP and WebSocket endpoints). See our [upgrading
+guidelines](./UPGRADING.md#v03424) for more details.
+
+### IMPROVEMENTS
+
+- `[rpc]` [\#9724](https://github.com/tendermint/tendermint/issues/9724) Remove
+  useless whitespace in RPC output (@adizere, @thanethomson)
+
+### BUG FIXES
+
+- `[rpc]` [\#9692](https://github.com/tendermint/tendermint/issues/9692) Remove
+  `Cache-Control` header response from `/check_tx` endpoint (@JayT106)
+
+## v0.34.23
+
+*Nov 9, 2022*
+
+This release introduces some new Prometheus metrics to help in determining what
+kinds of messages are consuming the most P2P bandwidth. This builds towards our
+broader goal of optimizing Tendermint bandwidth consumption, and will give us
+meaningful insights once we can establish these metrics for a number of chains.
+
+We now also return `Cache-Control` headers for select RPC endpoints to help
+facilitate caching.
+
+Special thanks to external contributors on this release: @JayT106
+
+### IMPROVEMENTS
+- `[p2p]` [\#9641](https://github.com/tendermint/tendermint/issues/9641) Add new
+  Envelope type and associated methods for sending and receiving Envelopes
+  instead of raw bytes. This also adds new metrics,
+  `tendermint_p2p_message_send_bytes_total` and
+  `tendermint_p2p_message_receive_bytes_total`, that expose how many bytes of
+  each message type have been sent.
+- `[rpc]` [\#9666](https://github.com/tendermint/tendermint/issues/9666) Enable
+  caching of RPC responses (@JayT106)
+
+  The following RPC endpoints will return `Cache-Control` headers with a maximum
+  age of 1 day:
+
+  - `/abci_info`
+  - `/block`, if `height` is supplied
+  - `/block_by_hash`
+  - `/block_results`, if `height` is supplied
+  - `/blockchain`
+  - `/check_tx`
+  - `/commit`, if `height` is supplied
+  - `/consensus_params`, if `height` is supplied
+  - `/genesis`
+  - `/genesis_chunked`
+  - `/tx`
+  - `/validators`, if `height` is supplied
+
+## v0.34.22
+
+This release includes several bug fixes, [one of
+which](https://github.com/tendermint/tendermint/pull/9518) we discovered while
+building up a baseline for v0.34 against which to compare our upcoming v0.37
+release during our [QA process](./docs/qa/).
+
+Special thanks to external contributors on this release: @RiccardoM
+
+### FEATURES
+
+- [rpc] [\#9423](https://github.com/tendermint/tendermint/pull/9423) Support
+  HTTPS URLs from the WebSocket client (@RiccardoM, @cmwaters)
+
+### BUG FIXES
+
+- [config] [\#9483](https://github.com/tendermint/tendermint/issues/9483)
+  Calling `tendermint init` would incorrectly leave out the new `[storage]`
+  section delimiter in the generated configuration file - this has now been
+  fixed
+- [p2p] [\#9500](https://github.com/tendermint/tendermint/issues/9500) Prevent
+  peers who have errored being added to the peer set (@jmalicevic)
+- [indexer] [\#9473](https://github.com/tendermint/tendermint/issues/9473) Fix
+  bug that caused the psql indexer to index empty blocks whenever one of the
+  transactions returned a non zero code. The relevant deduplication logic has
+  been moved within the kv indexer only (@cmwaters)
+- [blocksync] [\#9518](https://github.com/tendermint/tendermint/issues/9518) A
+  block sync stall was observed during our QA process whereby the node was
+  unable to make progress. Retrying block requests after a timeout fixes this.
+
+## v0.34.21
+
+Release highlights include:
+
+- A new `[storage]` configuration section and flag `discard_abci_responses`,
+  which, if enabled, discards all ABCI responses except the latest one in order
+  to reduce disk space usage in the state store. When enabled, the
+  `block_results` RPC endpoint can no longer function and will return an error.
+- A new CLI command, `reindex-event`, to re-index block and tx events to the
+  event sinks. You can run this command when the event store backend
+  dropped/disconnected or you want to replace the backend. When
+  `discard_abci_responses` is enabled, you will not be able to use this command.
+
+Special thanks to external contributors on this release: @rootwarp & @animart
+
+### FEATURES
+
+- [cli] [\#9083](https://github.com/tendermint/tendermint/issues/9083) Backport command to reindex missed events (@cmwaters)
+- [cli] [\#9107](https://github.com/tendermint/tendermint/issues/9107) Add the `p2p.external-address` argument to set the node P2P external address (@amimart)
+
+### IMPROVEMENTS
+
+- [config] [\#9054](https://github.com/tendermint/tendermint/issues/9054) `discard_abci_responses` flag added to discard all ABCI
+  responses except the last in order to save on storage space in the state
+  store (@samricotta)
+
+### BUG FIXES
+
+- [mempool] [\#9033](https://github.com/tendermint/tendermint/issues/9033) Rework lock discipline to mitigate callback deadlocks in the
+  priority mempool
+- [cli] [\#9103](https://github.com/tendermint/tendermint/issues/9103) fix unsafe-reset-all for working with home path (@rootwarp)
+
 ## v0.34.20
 
 Special thanks to external contributors on this release: @joeabbey @yihuang
@@ -438,7 +558,7 @@ Special thanks to external contributors on this release: @james-ray, @fedekunze,
 - [abci] [\#5174](https://github.com/tendermint/tendermint/pull/5174) Remove `MockEvidence` in favor of testing with actual evidence types (`DuplicateVoteEvidence` & `LightClientAttackEvidence`) (@cmwaters)
 - [abci] [\#5191](https://github.com/tendermint/tendermint/pull/5191) Add `InitChain.InitialHeight` field giving the initial block height (@erikgrinaker)
 - [abci] [\#5227](https://github.com/tendermint/tendermint/pull/5227) Add `ResponseInitChain.app_hash` which is recorded in genesis block (@erikgrinaker)
-- [config] [\#5147](https://github.com/tendermint/tendermint/pull/5147) Add `--consensus.double_sign_check_height` flag and `DoubleSignCheckHeight` config variable. See [ADR-51](https://github.com/tendermint/tendermint/blob/master/docs/architecture/adr-051-double-signing-risk-reduction.md) (@dongsam)
+- [config] [\#5147](https://github.com/tendermint/tendermint/pull/5147) Add `--consensus.double_sign_check_height` flag and `DoubleSignCheckHeight` config variable. See [ADR-51](https://github.com/tendermint/tendermint/blob/main/docs/architecture/adr-051-double-signing-risk-reduction.md) (@dongsam)
 - [db] [\#5233](https://github.com/tendermint/tendermint/pull/5233) Add support for `badgerdb` database backend (@erikgrinaker)
 - [evidence] [\#4532](https://github.com/tendermint/tendermint/pull/4532) Handle evidence from light clients (@melekes)
 - [evidence] [#4821](https://github.com/tendermint/tendermint/pull/4821) Amnesia (light client attack) evidence can be detected, verified and committed (@cmwaters)
@@ -452,7 +572,7 @@ Special thanks to external contributors on this release: @james-ray, @fedekunze,
 - [rpc] [\#5017](https://github.com/tendermint/tendermint/pull/5017) Add `/check_tx` endpoint to check transactions without executing them or adding them to the mempool (@melekes)
 - [rpc] [\#5108](https://github.com/tendermint/tendermint/pull/5108) Subscribe using the websocket for new evidence events (@cmwaters)
 - [statesync] Add state sync support, where a new node can be rapidly bootstrapped by fetching state snapshots from peers instead of replaying blocks. See the `[statesync]` config section.
-- [evidence] [\#5361](https://github.com/tendermint/tendermint/pull/5361) Add LightClientAttackEvidence and refactor evidence lifecycle - for more information see [ADR-059](https://github.com/tendermint/tendermint/blob/master/docs/architecture/adr-059-evidence-composition-and-lifecycle.md) (@cmwaters)
+- [evidence] [\#5361](https://github.com/tendermint/tendermint/pull/5361) Add LightClientAttackEvidence and refactor evidence lifecycle - for more information see [ADR-059](https://github.com/tendermint/tendermint/blob/main/docs/architecture/adr-059-evidence-composition-and-lifecycle.md) (@cmwaters)
 
 ### IMPROVEMENTS
 
@@ -532,7 +652,7 @@ This security release fixes:
 Tendermint 0.33.0 and above allow block proposers to include signatures for the
 wrong block. This may happen naturally if you start a network, have it run for
 some time and restart it **without changing the chainID**. (It is a
-[misconfiguration](https://docs.tendermint.com/master/tendermint-core/using-tendermint.html)
+[misconfiguration](https://docs.tendermint.com/v0.33/tendermint-core/using-tendermint.html)
 to reuse chainIDs.) Correct block proposers will accidentally include signatures
 for the wrong block if they see these signatures, and then commits won't validate,
 making all proposed blocks invalid. A malicious validator (even with a minimal
@@ -831,7 +951,7 @@ and a validator address plus a timestamp. Note we may remove the validator
 address & timestamp fields in the future (see ADR-25).
 
 `lite2` package has been added to solve `lite` issues and introduce weak
-subjectivity interface. Refer to the [spec](https://github.com/tendermint/spec/blob/master/spec/consensus/light-client.md) for complete details.
+subjectivity interface. Refer to the [spec](https://github.com/tendermint/tendermint/blob/v0.34.x/spec/consensus/light-client.md) for complete details.
 `lite` package is now deprecated and will be removed in v0.34 release.
 
 ### BREAKING CHANGES:
@@ -1192,7 +1312,7 @@ Special thanks to external contributors on this release: @jon-certik, @gracenoah
 *August 28, 2019*
 
 @climber73 wrote the [Writing a Tendermint Core application in Java
-(gRPC)](https://github.com/tendermint/tendermint/blob/master/docs/guides/java.md)
+(gRPC)](https://github.com/tendermint/tendermint/blob/v0.32.x/docs/guides/java.md)
 guide.
 
 Special thanks to external contributors on this release:
@@ -1225,7 +1345,7 @@ Special thanks to external contributors on this release:
 
 ### FEATURES:
 
-- [blockchain] [\#3561](https://github.com/tendermint/tendermint/issues/3561) Add early version of the new blockchain reactor, which is supposed to be more modular and testable compared to the old version. To try it, you'll have to change `version` in the config file, [here](https://github.com/tendermint/tendermint/blob/master/config/toml.go#L303) NOTE: It's not ready for a production yet. For further information, see [ADR-40](https://github.com/tendermint/tendermint/blob/master/docs/architecture/adr-040-blockchain-reactor-refactor.md) & [ADR-43](https://github.com/tendermint/tendermint/blob/master/docs/architecture/adr-043-blockchain-riri-org.md)
+- [blockchain] [\#3561](https://github.com/tendermint/tendermint/issues/3561) Add early version of the new blockchain reactor, which is supposed to be more modular and testable compared to the old version. To try it, you'll have to change `version` in the config file, [here](https://github.com/tendermint/tendermint/blob/v0.34.x/config/toml.go#L303) NOTE: It's not ready for a production yet. For further information, see [ADR-40](https://github.com/tendermint/tendermint/blob/main/docs/architecture/adr-040-blockchain-reactor-refactor.md) & [ADR-43](https://github.com/tendermint/tendermint/blob/main/docs/architecture/adr-043-blockchain-riri-org.md)
 - [mempool] [\#3826](https://github.com/tendermint/tendermint/issues/3826) Make `max_msg_bytes` configurable(@bluele)
 - [node] [\#3846](https://github.com/tendermint/tendermint/pull/3846) Allow replacing existing p2p.Reactor(s) using [`CustomReactors`
   option](https://godoc.org/github.com/tendermint/tendermint/node#CustomReactors).
@@ -1283,7 +1403,7 @@ This release contains a minor enhancement to the ABCI and some breaking changes
 
 - [p2p] [\#3338](https://github.com/tendermint/tendermint/issues/3338) Prevent "sent next PEX request too soon" errors by not calling
   ensurePeers outside of ensurePeersRoutine
-- [behavior] [\3772](https://github.com/tendermint/tendermint/pull/3772) Return correct reason in MessageOutOfOrder (@jim380)
+- [behaviour] [\3772](https://github.com/tendermint/tendermint/pull/3772) Return correct reason in MessageOutOfOrder (@jim380)
 - [config] [\#3723](https://github.com/tendermint/tendermint/issues/3723) Add consensus_params to testnet config generation; document time_iota_ms (@ashleyvega)
 
 
@@ -1542,7 +1662,7 @@ Special thanks to external contributors on this release:
 - [libs/db] [\#3611](https://github.com/tendermint/tendermint/issues/3611) Conditional compilation
   * Use `cleveldb` tag instead of `gcc` to compile Tendermint with CLevelDB or
     use `make build_c` / `make install_c` (full instructions can be found at
-    https://docs.tendermint.com/master/introduction/install.html#compile-with-cleveldb-support)
+    <https://docs.tendermint.com/>)
   * Use `boltdb` tag to compile Tendermint with bolt db
 - [node] [\#3362](https://github.com/tendermint/tendermint/issues/3362) Return an error if `persistent_peers` list is invalid (except
   when IP lookup fails)
@@ -1603,7 +1723,7 @@ It brings back `NetAddress()` to `NodeInfo` and uses it instead of `SocketAddr`
 Additionally, it improves response time on the `/validators` or `/status` RPC endpoints.
 As a side-effect it makes these RPC endpoint more difficult to DoS and fixes a performance degradation in `ExecCommitBlock`.
 Also, it contains an [ADR](https://github.com/tendermint/tendermint/pull/3539) that proposes decoupling the
-responsibility for peer behavior from the `p2p.Switch` (by @brapse).
+responsibility for peer behaviour from the `p2p.Switch` (by @brapse).
 
 Special thanks to external contributors on this release:
 @brapse, @guagualvcha, @mydring
@@ -1766,7 +1886,7 @@ more details.
   - [rpc] [\#3269](https://github.com/tendermint/tendermint/issues/2826) Limit number of unique clientIDs with open subscriptions. Configurable via `rpc.max_subscription_clients`
   - [rpc] [\#3269](https://github.com/tendermint/tendermint/issues/2826) Limit number of unique queries a given client can subscribe to at once. Configurable via `rpc.max_subscriptions_per_client`.
   - [rpc] [\#3435](https://github.com/tendermint/tendermint/issues/3435) Default ReadTimeout and WriteTimeout changed to 10s. WriteTimeout can increased by setting `rpc.timeout_broadcast_tx_commit` in the config.
-  - [rpc/client] [\#3269](https://github.com/tendermint/tendermint/issues/3269) Update `EventsClient` interface to reflect new pubsub/eventBus API [ADR-33](https://github.com/tendermint/tendermint/blob/master/docs/architecture/adr-033-pubsub.md). This includes `Subscribe`, `Unsubscribe`, and `UnsubscribeAll` methods.
+  - [rpc/client] [\#3269](https://github.com/tendermint/tendermint/issues/3269) Update `EventsClient` interface to reflect new pubsub/eventBus API [ADR-33](https://github.com/tendermint/tendermint/blob/main/docs/architecture/adr-033-pubsub.md). This includes `Subscribe`, `Unsubscribe`, and `UnsubscribeAll` methods.
 
 * Apps
   - [abci] [\#3403](https://github.com/tendermint/tendermint/issues/3403) Remove `time_iota_ms` from BlockParams. This is a
@@ -1819,7 +1939,7 @@ more details.
 - [blockchain] [\#3358](https://github.com/tendermint/tendermint/pull/3358) Fix timer leak in `BlockPool` (@guagualvcha)
 - [cmd] [\#3408](https://github.com/tendermint/tendermint/issues/3408) Fix `testnet` command's panic when creating non-validator configs (using `--n` flag) (@srmo)
 - [libs/db/remotedb/grpcdb] [\#3402](https://github.com/tendermint/tendermint/issues/3402) Close Iterator/ReverseIterator after use
-- [libs/pubsub] [\#951](https://github.com/tendermint/tendermint/issues/951), [\#1880](https://github.com/tendermint/tendermint/issues/1880) Use non-blocking send when dispatching messages [ADR-33](https://github.com/tendermint/tendermint/blob/master/docs/architecture/adr-033-pubsub.md)
+- [libs/pubsub] [\#951](https://github.com/tendermint/tendermint/issues/951), [\#1880](https://github.com/tendermint/tendermint/issues/1880) Use non-blocking send when dispatching messages [ADR-33](https://github.com/tendermint/tendermint/blob/main/docs/architecture/adr-033-pubsub.md)
 - [lite] [\#3364](https://github.com/tendermint/tendermint/issues/3364) Fix `/validators` and `/abci_query` proxy endpoints
   (@guagualvcha)
 - [p2p/conn] [\#3347](https://github.com/tendermint/tendermint/issues/3347) Reject all-zero shared secrets in the Diffie-Hellman step of secret-connection
@@ -2271,8 +2391,8 @@ Special thanks to external contributors on this release:
 - [blockchain] [\#2731](https://github.com/tendermint/tendermint/issues/2731) Retry both blocks if either is bad to avoid getting stuck during fast sync (@goolAdapter)
 - [consensus] [\#2893](https://github.com/tendermint/tendermint/issues/2893) Use genDoc.Validators instead of state.NextValidators on replay when appHeight==0 (@james-ray)
 - [log] [\#2868](https://github.com/tendermint/tendermint/issues/2868) Fix `module=main` setting overriding all others
-    - NOTE: this changes the default logging behavior to be much less verbose.
-      Set `log_level="info"` to restore the previous behavior.
+    - NOTE: this changes the default logging behaviour to be much less verbose.
+      Set `log_level="info"` to restore the previous behaviour.
 - [rpc] [\#2808](https://github.com/tendermint/tendermint/issues/2808) Fix `accum` field in `/validators` by calling `IncrementAccum` if necessary
 - [rpc] [\#2811](https://github.com/tendermint/tendermint/issues/2811) Allow integer IDs in JSON-RPC requests (@tomtau)
 - [txindex/kv] [\#2759](https://github.com/tendermint/tendermint/issues/2759) Fix tx.height range queries
@@ -2403,7 +2523,7 @@ increasing attention to backwards compatibility. Thanks for bearing with us!
   * [state] [\#2644](https://github.com/tendermint/tendermint/issues/2644) Add Version field to State, breaking the format of State as
     encoded on disk.
   * [rpc] [\#2298](https://github.com/tendermint/tendermint/issues/2298) `/abci_query` takes `prove` argument instead of `trusted` and switches the default
-    behavior to `prove=false`
+    behaviour to `prove=false`
   * [rpc] [\#2654](https://github.com/tendermint/tendermint/issues/2654) Remove all `node_info.other.*_version` fields in `/status` and
     `/net_info`
   * [rpc] [\#2636](https://github.com/tendermint/tendermint/issues/2636) Remove
@@ -2517,7 +2637,7 @@ Special thanks to external contributors on this release:
 This release is mostly about the ConsensusParams - removing fields and enforcing MaxGas.
 It also addresses some issues found via security audit, removes various unused
 functions from `libs/common`, and implements
-[ADR-012](https://github.com/tendermint/tendermint/blob/master/docs/architecture/adr-012-peer-transport.md).
+[ADR-012](https://github.com/tendermint/tendermint/blob/main/docs/architecture/adr-012-peer-transport.md).
 
 BREAKING CHANGES:
 
@@ -2548,7 +2668,7 @@ FEATURES:
 - [libs] [\#2286](https://github.com/tendermint/tendermint/issues/2286) Panic if `autofile` or `db/fsdb` permissions change from 0600.
 
 IMPROVEMENTS:
-- [libs/db] [\#2371](https://github.com/tendermint/tendermint/issues/2371) Output error instead of panic when the given `db_backend` is not initialized (@bradyjoestar)
+- [libs/db] [\#2371](https://github.com/tendermint/tendermint/issues/2371) Output error instead of panic when the given `db_backend` is not initialised (@bradyjoestar)
 - [mempool] [\#2399](https://github.com/tendermint/tendermint/issues/2399) Make mempool cache a proper LRU (@bradyjoestar)
 - [p2p] [\#2126](https://github.com/tendermint/tendermint/issues/2126) Introduce PeerTransport interface to improve isolation of concerns
 - [libs/common] [\#2326](https://github.com/tendermint/tendermint/issues/2326) Service returns ErrNotStarted
@@ -2598,7 +2718,7 @@ BREAKING CHANGES:
   - [abci] Added address of the original proposer of the block to Header
   - [abci] Change ABCI Header to match Tendermint exactly
   - [abci] [\#2159](https://github.com/tendermint/tendermint/issues/2159) Update use of `Validator` (see
-    [ADR-018](https://github.com/tendermint/tendermint/blob/master/docs/architecture/adr-018-ABCI-Validators.md)):
+    [ADR-018](https://github.com/tendermint/tendermint/blob/main/docs/architecture/adr-018-ABCI-Validators.md)):
     - Remove PubKey from `Validator` (so it's just Address and Power)
     - Introduce `ValidatorUpdate` (with just PubKey and Power)
     - InitChain and EndBlock use ValidatorUpdate
@@ -2620,7 +2740,7 @@ BREAKING CHANGES:
   - [state] [\#1815](https://github.com/tendermint/tendermint/issues/1815) Validator set changes are now delayed by one block (!)
     - Add NextValidatorSet to State, changes on-disk representation of state
   - [state] [\#2184](https://github.com/tendermint/tendermint/issues/2184) Enforce ConsensusParams.BlockSize.MaxBytes (See
-    [ADR-020](https://github.com/tendermint/tendermint/blob/master/docs/architecture/adr-020-block-size.md)).
+    [ADR-020](https://github.com/tendermint/tendermint/blob/main/docs/architecture/adr-020-block-size.md)).
     - Remove ConsensusParams.BlockSize.MaxTxs
     - Introduce maximum sizes for all components of a block, including ChainID
   - [types] Updates to the block Header:
@@ -2631,7 +2751,7 @@ BREAKING CHANGES:
   - [consensus] [\#2203](https://github.com/tendermint/tendermint/issues/2203) Implement BFT time
     - Timestamp in block must be monotonic and equal the median of timestamps in block's LastCommit
   - [crypto] [\#2239](https://github.com/tendermint/tendermint/issues/2239) Secp256k1 signature changes (See
-    [ADR-014](https://github.com/tendermint/tendermint/blob/master/docs/architecture/adr-014-secp-malleability.md)):
+    [ADR-014](https://github.com/tendermint/tendermint/blob/main/docs/architecture/adr-014-secp-malleability.md)):
     - format changed from DER to `r || s`, both little endian encoded as 32 bytes.
     - malleability removed by requiring `s` to be in canonical form.
 
@@ -3431,7 +3551,7 @@ Also includes the Grand Repo-Merge of 2017.
 BREAKING CHANGES:
 
 - Config and Flags:
-  - The `config` map is replaced with a [`Config` struct](https://github.com/tendermint/tendermint/blob/master/config/config.go#L11),
+  - The `config` map is replaced with a [`Config` struct](https://github.com/tendermint/tendermint/blob/v0.10.0/config/config.go#L11),
 containing substructs: `BaseConfig`, `P2PConfig`, `MempoolConfig`, `ConsensusConfig`, `RPCConfig`
   - This affects the following flags:
     - `--seeds` is now `--p2p.seeds`

CHANGELOG_PENDING.md

@@ -1,10 +1,6 @@
 # Unreleased Changes
 
-## v0.37.0
-
-Special thanks to external contributors on this release:
-
-Friendly reminder, we have a [bug bounty program](https://hackerone.com/tendermint).
+## v0.34.25
 
 ### BREAKING CHANGES
 
@@ -12,16 +8,10 @@ Friendly reminder, we have a [bug bounty program](https://hackerone.com/tendermi
 
 - Apps
 
-  - [abci/counter] \#6684 Delete counter example app
-  - [txResults] \#9175 Remove `gas_used` & `gas_wanted` from being merkelized in the lastresulthash in the header
-
 - P2P Protocol
 
 - Go API
 
-    - [all] [#9144] Change spelling from British English to American (@cmwaters)
-        - Rename "Subscription.Cancelled()" to "Subscription.Canceled()" in libs/pubsub
-
 - Blockchain Protocol
 
 ### FEATURES
@@ -30,4 +20,3 @@ Friendly reminder, we have a [bug bounty program](https://hackerone.com/tendermi
 
 ### BUG FIXES
 
-[docker] \#9073 enable cross platform build using docker buildx

CODE_OF_CONDUCT.md

@@ -1,109 +1,59 @@
 # The Tendermint Code of Conduct
 
-This code of conduct applies to all projects run by the Tendermint/COSMOS team
-and hence to Tendermint.
+This code of conduct applies to all projects run by the Tendermint/COSMOS team and hence to tendermint.
+
 
 ----
 
+
 # Conduct
 
 ## Contact: conduct@tendermint.com
 
-* We are committed to providing a friendly, safe and welcoming environment for
-  all, regardless of level of experience, gender, gender identity and
-  expression, sexual orientation, disability, personal appearance, body size,
-  race, ethnicity, age, religion, nationality, or other similar characteristic.
+* We are committed to providing a friendly, safe and welcoming environment for all, regardless of level of experience, gender, gender identity and expression, sexual orientation, disability, personal appearance, body size, race, ethnicity, age, religion, nationality, or other similar characteristic.
 
-* On Slack, please avoid using overtly sexual nicknames or other nicknames that
-  might detract from a friendly, safe and welcoming environment for all.
+* On Slack, please avoid using overtly sexual nicknames or other nicknames that might detract from a friendly, safe and welcoming environment for all.
 
 * Please be kind and courteous. There’s no need to be mean or rude.
 
-* Respect that people have differences of opinion and that every design or
-  implementation choice carries a trade-off and numerous costs. There is seldom
-  a right answer.
+* Respect that people have differences of opinion and that every design or implementation choice carries a trade-off and numerous costs. There is seldom a right answer.
 
-* Please keep unstructured critique to a minimum. If you have solid ideas you
-  want to experiment with, make a fork and see how it works.
+* Please keep unstructured critique to a minimum. If you have solid ideas you want to experiment with, make a fork and see how it works.
 
-* We will exclude you from interaction if you insult, demean or harass anyone.
-  That is not welcome behavior. We interpret the term “harassment” as including
-  the definition in the [Citizen Code of Conduct][ccoc]; if you have any lack of
-  clarity about what might be included in that concept, please read their
-  definition. In particular, we don’t tolerate behavior that excludes people in
-  socially marginalized groups.
+* We will exclude you from interaction if you insult, demean or harass anyone. That is not welcome behaviour. We interpret the term “harassment” as including the definition in the [Citizen Code of Conduct](http://citizencodeofconduct.org/); if you have any lack of clarity about what might be included in that concept, please read their definition. In particular, we don’t tolerate behavior that excludes people in socially marginalized groups.
 
-* Private harassment is also unacceptable. No matter who you are, if you feel
-  you have been or are being harassed or made uncomfortable by a community
-  member, please contact one of the channel admins or the person mentioned above
-  immediately. Whether you’re a regular contributor or a newcomer, we care about
-  making this community a safe place for you and we’ve got your back.
+* Private harassment is also unacceptable. No matter who you are, if you feel you have been or are being harassed or made uncomfortable by a community member, please contact one of the channel admins or the person mentioned above immediately. Whether you’re a regular contributor or a newcomer, we care about making this community a safe place for you and we’ve got your back.
+
+* Likewise any spamming, trolling, flaming, baiting or other attention-stealing behaviour is not welcome.
 
-* Likewise any spamming, trolling, flaming, baiting or other attention-stealing
-  behavior is not welcome.
 
 ----
 
+
 # Moderation
 
-These are the policies for upholding our community’s standards of conduct. If
-you feel that a thread needs moderation, please contact the above mentioned
-person.
+These are the policies for upholding our community’s standards of conduct. If you feel that a thread needs moderation, please contact the above mentioned person.
 
-1. Remarks that violate the Tendermint/COSMOS standards of conduct, including
-   hateful, hurtful, oppressive, or exclusionary remarks, are not allowed.
-   (Cursing is allowed, but never targeting another user, and never in a hateful
-   manner.)
+1. Remarks that violate the Tendermint/COSMOS standards of conduct, including hateful, hurtful, oppressive, or exclusionary remarks, are not allowed. (Cursing is allowed, but never targeting another user, and never in a hateful manner.)
 
-2. Remarks that moderators find inappropriate, whether listed in the code of
-   conduct or not, are also not allowed.
+2. Remarks that moderators find inappropriate, whether listed in the code of conduct or not, are also not allowed.
 
 3. Moderators will first respond to such remarks with a warning.
 
-4. If the warning is unheeded, the user will be “kicked,” i.e., kicked out of
-   the communication channel to cool off.
+4. If the warning is unheeded, the user will be “kicked,” i.e., kicked out of the communication channel to cool off.
 
-5. If the user comes back and continues to make trouble, they will be banned,
-   i.e., indefinitely excluded.
+5. If the user comes back and continues to make trouble, they will be banned, i.e., indefinitely excluded.
 
-6. Moderators may choose at their discretion to un-ban the user if it was a
-   first offense and they offer the offended party a genuine apology.
+6. Moderators may choose at their discretion to un-ban the user if it was a first offense and they offer the offended party a genuine apology.
 
-7. If a moderator bans someone and you think it was unjustified, please take it
-   up with that moderator, or with a different moderator, in private. Complaints
-   about bans in-channel are not allowed.
+7. If a moderator bans someone and you think it was unjustified, please take it up with that moderator, or with a different moderator, in private. Complaints about bans in-channel are not allowed.
 
-8. Moderators are held to a higher standard than other community members. If a
-   moderator creates an inappropriate situation, they should expect less leeway
-   than others.
+8. Moderators are held to a higher standard than other community members. If a moderator creates an inappropriate situation, they should expect less leeway than others.
 
-In the Tendermint/COSMOS community we strive to go the extra step to look out
-for each other. Don’t just aim to be technically unimpeachable, try to be your
-best self. In particular, avoid flirting with offensive or sensitive issues,
-particularly if they’re off-topic; this all too often leads to unnecessary
-fights, hurt feelings, and damaged trust; worse, it can drive people away
-from the community entirely.
+In the Tendermint/COSMOS community we strive to go the extra step to look out for each other. Don’t just aim to be technically unimpeachable, try to be your best self. In particular, avoid flirting with offensive or sensitive issues, particularly if they’re off-topic; this all too often leads to unnecessary fights, hurt feelings, and damaged trust; worse, it can drive people away from the community entirely.
 
-And if someone takes issue with something you said or did, resist the urge to be
-defensive. Just stop doing what it was they complained about and apologize. Even
-if you feel you were misinterpreted or unfairly accused, chances are good there
-was something you could’ve communicated better — remember that it’s your
-responsibility to make your fellow Cosmonauts comfortable. Everyone wants to
-get along and we are all here first and foremost because we want to talk
-about cool technology. You will find that people will be eager to assume
-good intent and forgive as long as you earn their trust.
+And if someone takes issue with something you said or did, resist the urge to be defensive. Just stop doing what it was they complained about and apologize. Even if you feel you were misinterpreted or unfairly accused, chances are good there was something you could’ve communicated better — remember that it’s your responsibility to make your fellow Cosmonauts comfortable. Everyone wants to get along and we are all here first and foremost because we want to talk about cool technology. You will find that people will be eager to assume good intent and forgive as long as you earn their trust.
 
-The enforcement policies listed above apply to all official Tendermint/COSMOS
-venues. For other projects adopting the Tendermint/COSMOS Code of Conduct,
-please contact the maintainers of those projects for enforcement. If you wish to
-use this code of conduct for your own project, consider explicitly mentioning
-your moderation policy or making a copy with your own moderation policy so as to
-avoid confusion.
+The enforcement policies listed above apply to all official Tendermint/COSMOS venues.For other projects adopting the Tendermint/COSMOS Code of Conduct, please contact the maintainers of those projects for enforcement. If you wish to use this code of conduct for your own project, consider explicitly mentioning your moderation policy or making a copy with your own moderation policy so as to avoid confusion.
 
-\*Adapted from the [Node.js Policy on Trolling][node-trolling-policy], the
-[Contributor Covenant v1.3.0][ccov] and the [Rust Code of Conduct][rust-coc].
-
-[ccoc]: https://github.com/stumpsyn/policies/blob/master/citizen_code_of_conduct.md
-[node-trolling-policy]: http://blog.izs.me/post/30036893703/policy-on-trolling
-[ccov]: http://contributor-covenant.org/version/1/3/0/
-[rust-coc]: https://www.rust-lang.org/en-US/conduct.html
+*Adapted from the [Node.js Policy on Trolling](http://blog.izs.me/post/30036893703/policy-on-trolling), the [Contributor Covenant v1.3.0](http://contributor-covenant.org/version/1/3/0/) and the [Rust Code of Conduct](https://www.rust-lang.org/en-US/conduct.html).

CONTRIBUTING.md

@@ -26,8 +26,7 @@ will indicate their support with a heartfelt emoji.
 
 If the issue would benefit from thorough discussion, maintainers may
 request that you create a [Request For
-Comment](https://github.com/tendermint/spec/tree/master/rfc)
-in the Tendermint spec repo. Discussion
+Comment](https://github.com/tendermint/tendermint/tree/main/rfc). Discussion
 at the RFC stage will build collective understanding of the dimensions
 of the problems and help structure conversations around trade-offs.
 
@@ -105,47 +104,24 @@ specify exactly the dependency you want to update, eg.
 
 ## Protobuf
 
-We use [Protocol Buffers](https://developers.google.com/protocol-buffers) along
-with [`gogoproto`](https://github.com/gogo/protobuf) to generate code for use
-across Tendermint Core.
+We use [Protocol Buffers](https://developers.google.com/protocol-buffers) along with [gogoproto](https://github.com/gogo/protobuf) to generate code for use across Tendermint Core.
 
-To generate proto stubs, lint, and check protos for breaking changes, you will
-need to install [buf](https://buf.build/) and `gogoproto`. Then, from the root
-of the repository, run:
+For linting and checking breaking changes, we use [buf](https://buf.build/). If you would like to run linting and check if the changes you have made are breaking then you will need to have docker running locally. Then the linting cmd will be `make proto-lint` and the breaking changes check will be `make proto-check-breaking`.
 
-```bash
-# Lint all of the .proto files in proto/tendermint
-make proto-lint
+We use [Docker](https://www.docker.com/) to generate the protobuf stubs. To generate the stubs yourself, make sure docker is running then run `make proto-gen`.
 
-# Check if any of your local changes (prior to committing to the Git repository)
-# are breaking
-make proto-check-breaking
+## Vagrant
 
-# Generate Go code from the .proto files in proto/tendermint
-make proto-gen
-```
+If you are a [Vagrant](https://www.vagrantup.com/) user, you can get started
+hacking Tendermint with the commands below.
 
-To automatically format `.proto` files, you will need
-[`clang-format`](https://clang.llvm.org/docs/ClangFormat.html) installed. Once
-installed, you can run:
+NOTE: In case you installed Vagrant in 2017, you might need to run
+`vagrant box update` to upgrade to the latest `ubuntu/xenial64`.
 
-```bash
-make proto-format
-```
-
-### Visual Studio Code
-
-If you are a VS Code user, you may want to add the following to your `.vscode/settings.json`:
-
-```json
-{
-  "protoc": {
-    "options": [
-      "--proto_path=${workspaceRoot}/proto",
-      "--proto_path=${workspaceRoot}/third_party/proto"
-    ]
-  }
-}
+```sh
+vagrant up
+vagrant ssh
+make test
 ```
 
 ## Changelog
@@ -249,6 +225,89 @@ Fixes #nnnn
 
 Each PR should have one commit once it lands on `master`; this can be accomplished by using the "squash and merge" button on Github. Be sure to edit your commit message, though!
 
+### Release Procedure
+
+#### Major Release
+
+1. Start on `master`
+2. Run integration tests (see `test_integrations` in Makefile)
+3. Prepare release in a pull request against `master` (to be squash merged):
+   - Copy `CHANGELOG_PENDING.md` to top of `CHANGELOG.md`; if this release
+      had release candidates, squash all the RC updates into one
+   - Run `python ./scripts/linkify_changelog.py CHANGELOG.md` to add links for
+     all issues
+   - run `bash ./scripts/authors.sh` to get a list of authors since the latest
+     release, and add the github aliases of external contributors to the top of
+     the changelog. To lookup an alias from an email, try `bash ./scripts/authors.sh <email>`
+   - Reset the `CHANGELOG_PENDING.md`
+   - Bump TMVersionDefault version in  `version.go`
+   - Bump P2P and block protocol versions in  `version.go`, if necessary
+   - Bump ABCI protocol version in `version.go`, if necessary
+   - Make sure all significant breaking changes are covered in `UPGRADING.md`
+   - Add any release notes you would like to be added to the body of the release to `release_notes.md`.
+4. Push a tag with prepared release details (this will trigger the release `vX.X.0`)
+   - `git tag -a vX.X.x -m 'Release vX.X.x'`
+   - `git push origin vX.X.x`
+5. Update the changelog.md file on master with the releases changelog.
+6. Delete any RC branches and tags for this release (if applicable)
+
+#### Minor Release
+
+Minor releases are done differently from major releases: They are built off of long-lived release candidate branches, rather than from master.
+
+1. Checkout the long-lived release candidate branch: `git checkout rcX/vX.X.X`
+2. Run integration tests: `make test_integrations`
+3. Prepare the release:
+   - copy `CHANGELOG_PENDING.md` to top of `CHANGELOG.md`
+   - run `python ./scripts/linkify_changelog.py CHANGELOG.md` to add links for all issues
+   - run `bash ./scripts/authors.sh` to get a list of authors since the latest release, and add the GitHub aliases of external contributors to the top of the CHANGELOG. To lookup an alias from an email, try `bash ./scripts/authors.sh <email>`
+   - reset the `CHANGELOG_PENDING.md`
+   - bump P2P and block protocol versions in  `version.go`, if necessary
+   - bump ABCI protocol version in `version.go`, if necessary
+   - make sure all significant breaking changes are covered in `UPGRADING.md`
+   - Add any release notes you would like to be added to the body of the release to `release_notes.md`.
+4. Create a release branch `release/vX.X.x` off the release candidate branch:
+   - `git checkout -b release/vX.X.x`
+   - `git push -u origin release/vX.X.x`
+   - Note that all branches prefixed with `release` are protected once pushed. You will need admin help to make any changes to the branch.
+5. Once the release branch has been approved, make sure to pull it locally, then push a tag.
+   - `git tag -a vX.X.x -m 'Release vX.X.x'`
+   - `git push origin vX.X.x`
+6. Create a pull request back to master with the CHANGELOG & version changes from the latest release.
+   - Remove all `R:minor` labels from the pull requests that were included in the release.
+   - Do not merge the release branch into master.
+7. Delete the former long lived release candidate branch once the release has been made.
+8. Create a new release candidate branch to be used for the next release.
+
+#### Backport Release
+
+1. start from the existing release branch you want to backport changes to (e.g. v0.30)
+   Branch to a release/vX.X.X branch locally (e.g. release/v0.30.7)
+2. Cherry pick the commit(s) that contain the changes you want to backport (usually these commits are from squash-merged PRs which were already reviewed)
+3. Follow steps 2 and 3 from [Major Release](#major-release)
+4. Push changes to release/vX.X.X branch
+5. Open a PR against the existing vX.X branch
+
+#### Release Candidates
+
+Before creating an official release, especially a major release, we may want to create a
+release candidate (RC) for our friends and partners to test out. We use git tags to
+create RCs, and we build them off of RC branches. RC branches typically have names formatted
+like `RCX/vX.X.X` (or, concretely, `RC0/v0.34.0`), while the tags themselves follow
+the "standard" release naming conventions, with `-rcX` at the end (`vX.X.X-rcX`).
+
+(Note that branches and tags _cannot_ have the same names, so it's important that these branches
+have distinct names from the tags/release names.)
+
+1. Start from the RC branch (e.g. `RC0/v0.34.0`).
+2. Create the new tag, specifying a name and a tag "message":  
+   `git tag -a v0.34.0-rc0 -m "Release Candidate v0.34.0-rc0` 
+3. Push the tag back up to origin:  
+   `git push origin v0.34.0-rc4`  
+   Now the tag should be available on the repo's releases page. 
+4. Create a new release candidate branch for any possible updates to the RC:  
+   `git checkout -b RC1/v0.34.0; git push origin RC1/v0.34.0`
+
 ## Testing
 
 ### Unit tests
@@ -281,6 +340,15 @@ cd test/e2e && \
   ./build/runner -f networks/ci.toml
 ```
 
+### Maverick
+
+**If you're changing the code in `consensus` package, please make sure to
+replicate all the changes in `./test/maverick/consensus`**. Maverick is a
+byzantine node used to assert that the validator gets punished for malicious
+behavior.
+
+See [README](./test/maverick/README.md) for details.
+
 ### Model-based tests (ADVANCED)
 
 *NOTE: if you're just submitting your first PR, you won't need to touch these
@@ -325,10 +393,8 @@ information.
 
 ### RPC Testing
 
-**If you contribute to the RPC endpoints it's important to document your
-changes in the [Openapi file](./rpc/openapi/openapi.yaml)**.
-
-To test your changes you must install `nodejs` and run:
+If you contribute to the RPC endpoints it's important to document your changes in the [Openapi file](./rpc/openapi/openapi.yaml)
+To test your changes you should install `nodejs` and run:
 
 ```bash
 npm i -g dredd

DOCKER/Dockerfile

@@ -1,14 +1,14 @@
 # stage 1 Generate Tendermint Binary
-FROM --platform=$BUILDPLATFORM golang:1.18-alpine as builder
+FROM golang:1.18-alpine as builder
 RUN apk update && \
     apk upgrade && \
     apk --no-cache add make
 COPY / /tendermint
 WORKDIR /tendermint
-RUN TARGETPLATFORM=$TARGETPLATFORM make build-linux
+RUN make build-linux
 
 # stage 2
-FROM golang:1.15-alpine
+FROM golang:1.18-alpine
 LABEL maintainer="hello@tendermint.com"
 
 # Tendermint will be looking for the genesis file in /tendermint/config/genesis.json

DOCKER/README.md

@@ -6,7 +6,7 @@ DockerHub tags for official releases are [here](https://hub.docker.com/r/tenderm
 
 Official releases can be found [here](https://github.com/tendermint/tendermint/releases).
 
-The Dockerfile for tendermint is not expected to change in the near future. The master file used for all builds can be found [here](https://raw.githubusercontent.com/tendermint/tendermint/master/DOCKER/Dockerfile).
+The Dockerfile for tendermint is not expected to change in the near future. The master file used for all builds can be found [here](https://raw.githubusercontent.com/tendermint/tendermint/main/DOCKER/Dockerfile).
 
 Respective versioned files can be found <https://raw.githubusercontent.com/tendermint/tendermint/vX.XX.XX/DOCKER/Dockerfile> (replace the Xs with the version number).
 
@@ -20,9 +20,9 @@ Respective versioned files can be found <https://raw.githubusercontent.com/tende
 
 Tendermint Core is Byzantine Fault Tolerant (BFT) middleware that takes a state transition machine, written in any programming language, and securely replicates it on many machines.
 
-For more background, see the [the docs](https://docs.tendermint.com/master/introduction/#quick-start).
+For more background, see the [the docs](https://docs.tendermint.com/v0.34/introduction/#quick-start).
 
-To get started developing applications, see the [application developers guide](https://docs.tendermint.com/master/introduction/quick-start.html).
+To get started developing applications, see the [application developers guide](https://docs.tendermint.com/v0.34/introduction/quick-start.html).
 
 ## How to use this image
 
@@ -37,7 +37,7 @@ docker run -it --rm -v "/tmp:/tendermint" tendermint/tendermint node --proxy_app
 
 ## Local cluster
 
-To run a 4-node network, see the `Makefile` in the root of [the repo](https://github.com/tendermint/tendermint/blob/master/Makefile) and run:
+To run a 4-node network, see the `Makefile` in the root of [the repo](https://github.com/tendermint/tendermint/blob/v0.34.x/Makefile) and run:
 
 ```sh
 make build-linux
@@ -49,8 +49,8 @@ Note that this will build and use a different image than the ones provided here.
 
 ## License
 
-- Tendermint's license is [Apache 2.0](https://github.com/tendermint/tendermint/blob/master/LICENSE).
+- Tendermint's license is [Apache 2.0](https://github.com/tendermint/tendermint/blob/main/LICENSE).
 
 ## Contributing
 
-Contributions are most welcome! See the [contributing file](https://github.com/tendermint/tendermint/blob/master/CONTRIBUTING.md) for more information.
+Contributions are most welcome! See the [contributing file](https://github.com/tendermint/tendermint/blob/main/CONTRIBUTING.md) for more information.

LICENSE

@@ -1,5 +1,3 @@
-Tendermint Core
-License: Apache2.0
 
                                  Apache License
                            Version 2.0, January 2004
@@ -181,7 +179,7 @@ License: Apache2.0
    APPENDIX: How to apply the Apache License to your work.
 
       To apply the Apache License to your work, attach the following
-      boilerplate notice, with the fields enclosed by brackets "{}"
+      boilerplate notice, with the fields enclosed by brackets "[]"
       replaced with your own identifying information. (Don't include
       the brackets!)  The text should be enclosed in the appropriate
       comment syntax for the file format. We also recommend that a
@@ -189,7 +187,7 @@ License: Apache2.0
       same "printed page" as the copyright notice for easier
       identification within third-party archives.
 
-   Copyright 2016 All in Bits, Inc
+   Copyright [yyyy] [name of copyright owner]
 
    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.

Makefile

@@ -1,6 +1,5 @@
 PACKAGES=$(shell go list ./...)
-BUILDDIR?=$(CURDIR)/build
-OUTPUT?=$(BUILDDIR)/tendermint
+OUTPUT?=build/tendermint
 
 BUILD_TAGS?=tendermint
 
@@ -53,67 +52,6 @@ endif
 # allow users to pass additional flags via the conventional LDFLAGS variable
 LD_FLAGS += $(LDFLAGS)
 
-# Process Docker environment varible TARGETPLATFORM 
-# in order to build binary with correspondent ARCH
-# by default will always build for linux/amd64
-TARGETPLATFORM ?= 
-GOOS ?= linux
-GOARCH ?= amd64
-GOARM ?=
-
-ifeq (linux/arm,$(findstring linux/arm,$(TARGETPLATFORM)))
-	GOOS=linux
-	GOARCH=arm
-	GOARM=7
-endif
-
-ifeq (linux/arm/v6,$(findstring linux/arm/v6,$(TARGETPLATFORM)))
-	GOOS=linux
-	GOARCH=arm
-	GOARM=6
-endif
-
-ifeq (linux/arm64,$(findstring linux/arm64,$(TARGETPLATFORM)))
-	GOOS=linux
-	GOARCH=arm64
-	GOARM=7
-endif
-
-ifeq (linux/386,$(findstring linux/386,$(TARGETPLATFORM)))
-	GOOS=linux
-	GOARCH=386
-endif
-
-ifeq (linux/amd64,$(findstring linux/amd64,$(TARGETPLATFORM)))
-	GOOS=linux
-	GOARCH=amd64
-endif
-
-ifeq (linux/mips,$(findstring linux/mips,$(TARGETPLATFORM)))
-	GOOS=linux
-	GOARCH=mips
-endif
-
-ifeq (linux/mipsle,$(findstring linux/mipsle,$(TARGETPLATFORM)))
-	GOOS=linux
-	GOARCH=mipsle
-endif
-
-ifeq (linux/mips64,$(findstring linux/mips64,$(TARGETPLATFORM)))
-	GOOS=linux
-	GOARCH=mips64
-endif
-
-ifeq (linux/mips64le,$(findstring linux/mips64le,$(TARGETPLATFORM)))
-	GOOS=linux
-	GOARCH=mips64le
-endif
-
-ifeq (linux/riscv64,$(findstring linux/riscv64,$(TARGETPLATFORM)))
-	GOOS=linux
-	GOARCH=riscv64
-endif
-
 all: check build test install
 .PHONY: all
 
@@ -262,7 +200,7 @@ format:
 
 lint:
 	@echo "--> Running linter"
-	@golangci-lint run
+	@go run github.com/golangci/golangci-lint/cmd/golangci-lint run
 .PHONY: lint
 
 DESTINATION = ./index.html.md
@@ -289,11 +227,6 @@ sync-docs:
 	aws cloudfront create-invalidation --distribution-id ${CF_DISTRIBUTION_ID} --profile terraform --path "/*" ;
 .PHONY: sync-docs
 
-# Verify that important design docs have ToC entries.
-check-docs-toc:
-	@./docs/presubmit.sh
-.PHONY: check-docs-toc
-
 ###############################################################################
 ###                            Docker image                                 ###
 ###############################################################################
@@ -310,7 +243,7 @@ build-docker: build-linux
 
 # Build linux binary on other platforms
 build-linux:
-	GOOS=$(GOOS) GOARCH=$(GOARCH) GOARM=$(GOARM) $(MAKE) build
+	GOOS=linux GOARCH=amd64 $(MAKE) build
 .PHONY: build-linux
 
 build-docker-localnode:
@@ -353,25 +286,3 @@ endif
 contract-tests:
 	dredd
 .PHONY: contract-tests
-
-# Implements test splitting and running. This is pulled directly from
-# the github action workflows for better local reproducibility.
-
-GO_TEST_FILES != find $(CURDIR) -name "*_test.go"
-
-# default to four splits by default
-NUM_SPLIT ?= 4
-
-$(BUILDDIR):
-	mkdir -p $@
-
-# The format statement filters out all packages that don't have tests.
-# Note we need to check for both in-package tests (.TestGoFiles) and
-# out-of-package tests (.XTestGoFiles).
-$(BUILDDIR)/packages.txt:$(GO_TEST_FILES) $(BUILDDIR)
-	go list -f "{{ if (or .TestGoFiles .XTestGoFiles) }}{{ .ImportPath }}{{ end }}" ./... | sort > $@
-
-split-test-packages:$(BUILDDIR)/packages.txt
-	split -d -n l/$(NUM_SPLIT) $< $<.
-test-group-%:split-test-packages
-	cat $(BUILDDIR)/packages.txt.$* | xargs go test -mod=readonly -timeout=5m -race -coverprofile=$(BUILDDIR)/$*.profile.out

README.md

@@ -1,5 +1,9 @@
 # Tendermint
 
+_UPDATE: TendermintCore featureset is frozen for LTS, see issue https://github.com/tendermint/tendermint/issues/9972_<br/>
+_This is the latest stable release used by cosmoshub-4, version 0.34.24_<br/>
+_The previous main branch (v0.38.xx) can now be found under "main_backup"_<br/>
+
 ![banner](docs/tendermint-core-image.jpg)
 
 [Byzantine-Fault Tolerant][bft] [State Machine Replication][smr]. Or
@@ -10,12 +14,11 @@
 [![Go version][go-badge]][go-url]
 [![Discord chat][discord-badge]][discord-url]
 [![License][license-badge]][license-url]
-[![tendermint/tendermint][loc-badge]][loc-url]
 [![Sourcegraph][sg-badge]][sg-url]
 
-| Branch | Tests                 | Coverage                                 | Linting             |
-|--------|-----------------------|------------------------------------------|---------------------|
-| main   | ![Tests][tests-badge] | [![codecov][codecov-badge]][codecov-url] | ![Lint][lint-badge] |
+| Branch | Tests                              | Linting                         |
+|--------|------------------------------------|---------------------------------|
+| main   | [![Tests][tests-badge]][tests-url] | [![Lint][lint-badge]][lint-url] |
 
 Tendermint Core is a Byzantine Fault Tolerant (BFT) middleware that takes a
 state transition machine - written in any programming language - and securely
@@ -43,20 +46,15 @@ since we are making breaking changes to the protocol and the APIs. See below for
 more details about [versioning](#versioning).
 
 In any case, if you intend to run Tendermint in production, we're happy to help.
-You can contact us [over email](mailto:hello@interchain.io) or [join the
-chat](https://discord.gg/cosmosnetwork).
+You can contact us [over email](mailto:hello@newtendermint.org) or [join the
+chat](https://discord.gg/gnoland).
 
 More on how releases are conducted can be found [here](./RELEASES.md).
 
 ## Security
 
-To report a security vulnerability, see our [bug bounty
-program](https://hackerone.com/cosmos). For examples of the kinds of bugs we're
-looking for, see [our security policy](SECURITY.md).
-
-We also maintain a dedicated mailing list for security updates. We will only
-ever use this mailing list to notify you of vulnerabilities and fixes in
-Tendermint Core. You can subscribe [here](http://eepurl.com/gZ5hQD).
+To report a security vulnerability, please [email us](mailto:security@newtendermint.org).
+For examples of the kinds of bugs we're looking for, see [our security policy](SECURITY.md).
 
 ## Minimum requirements
 
@@ -146,15 +144,10 @@ Upgrading instructions can be found in [UPGRADING.md](./UPGRADING.md).
 
 ## Join us!
 
-Tendermint Core is maintained by [Interchain GmbH](https://interchain.berlin).
-If you'd like to work full-time on Tendermint Core,
-[we're hiring](https://interchain-gmbh.breezy.hr/)!
-
-Funding for Tendermint Core development comes primarily from the
-[Interchain Foundation](https://interchain.io), a Swiss non-profit. The
-Tendermint trademark is owned by [Tendermint Inc.](https://tendermint.com), the
-for-profit entity that also maintains [tendermint.com](https://tendermint.com).
-
+The development of Tendermint Core was led primarily by All in Bits, Inc. The
+Tendermint trademark is owned by New Tendermint, LLC.  If you'd like to work
+full-time on Tendermint2 or [gno.land](https://gno.land), [we're
+hiring](mailto:hiring@newtendermint.org)!
 
 [bft]: https://en.wikipedia.org/wiki/Byzantine_fault_tolerance
 [smr]: https://en.wikipedia.org/wiki/State_machine_replication
@@ -163,17 +156,15 @@ for-profit entity that also maintains [tendermint.com](https://tendermint.com).
 [version-url]: https://github.com/tendermint/tendermint/releases/latest
 [api-badge]: https://camo.githubusercontent.com/915b7be44ada53c290eb157634330494ebe3e30a/68747470733a2f2f676f646f632e6f72672f6769746875622e636f6d2f676f6c616e672f6764646f3f7374617475732e737667
 [api-url]: https://pkg.go.dev/github.com/tendermint/tendermint
-[go-badge]: https://img.shields.io/badge/go-1.17-blue.svg
+[go-badge]: https://img.shields.io/badge/go-1.18-blue.svg
 [go-url]: https://github.com/moovweb/gvm
 [discord-badge]: https://img.shields.io/discord/669268347736686612.svg
 [discord-url]: https://discord.gg/cosmosnetwork
 [license-badge]: https://img.shields.io/github/license/tendermint/tendermint.svg
 [license-url]: https://github.com/tendermint/tendermint/blob/main/LICENSE
-[loc-badge]: https://tokei.rs/b1/github/tendermint/tendermint?category=lines
-[loc-url]: https://github.com/tendermint/tendermint
 [sg-badge]: https://sourcegraph.com/github.com/tendermint/tendermint/-/badge.svg
 [sg-url]: https://sourcegraph.com/github.com/tendermint/tendermint?badge
-[tests-badge]: https://github.com/tendermint/tendermint/workflows/Tests/badge.svg?branch=main
-[codecov-badge]: https://codecov.io/gh/tendermint/tendermint/branch/main/graph/badge.svg
-[codecov-url]: https://codecov.io/gh/tendermint/tendermint
-[lint-badge]: https://github.com/tendermint/tendermint/workflows/Lint/badge.svg
+[tests-url]: https://github.com/tendermint/tendermint/actions/workflows/tests.yml
+[tests-badge]: https://github.com/tendermint/tendermint/actions/workflows/tests.yml/badge.svg?branch=main
+[lint-badge]: https://github.com/tendermint/tendermint/actions/workflows/lint.yml/badge.svg
+[lint-url]: https://github.com/tendermint/tendermint/actions/workflows/lint.yml

RELEASES.md

@@ -1,345 +0,0 @@
-# Releases
-
-Tendermint uses modified [semantic versioning](https://semver.org/) with each
-release following a `vX.Y.Z` format. Tendermint is currently on major version 0
-and uses the minor version to signal breaking changes. The `main` branch is
-used for active development and thus it is not advisable to build against it.
-
-The latest changes are always initially merged into `main`. Releases are
-specified using tags and are built from long-lived "backport" branches that are
-cut from `main` when the release process begins. Each release "line" (e.g.
-0.34 or 0.33) has its own long-lived backport branch, and the backport branches
-have names like `v0.34.x` or `v0.33.x` (literally, `x`; it is not a placeholder
-in this case). Tendermint only maintains the last two releases at a time (the
-oldest release is predominantly just security patches).
-
-## Backporting
-
-As non-breaking changes land on `main`, they should also be backported to
-these backport branches.
-
-We use Mergify's [backport feature](https://mergify.io/features/backports) to
-automatically backport to the needed branch. There should be a label for any
-backport branch that you'll be targeting. To notify the bot to backport a pull
-request, mark the pull request with the label corresponding to the correct
-backport branch. For example, to backport to v0.35.x, add the label
-`S:backport-to-v0.35.x`. Once the original pull request is merged, the bot will
-try to cherry-pick the pull request to the backport branch. If the bot fails to
-backport, it will open a pull request. The author of the original pull request
-is responsible for solving the conflicts and merging the pull request.
-
-### Creating a backport branch
-
-If this is the first release candidate for a minor version release, e.g.
-v0.25.0, you get to have the honor of creating the backport branch!
-
-Note that, after creating the backport branch, you'll also need to update the
-tags on `main` so that `go mod` is able to order the branches correctly. You
-should tag `main` with a "dev" tag that is "greater than" the backport
-branches tags. See [#6072](https://github.com/tendermint/tendermint/pull/6072)
-for more context.
-
-In the following example, we'll assume that we're making a backport branch for
-the 0.35.x line.
-
-1. Start on `main`
-
-2. Create and push the backport branch:
-   ```sh
-   git checkout -b v0.35.x
-   git push origin v0.35.x
-   ```
-
-3. Create a PR to update the documentation directory for the backport branch.
-
-   We only maintain RFC and ADR documents on main, to avoid confusion. In
-   addition, we rewrite Markdown URLs pointing to main to point to the
-   backport branch, so that generated documentation will link to the correct
-   versions of files elsewhere in the repository. For context on the latter, see
-   https://github.com/tendermint/tendermint/issues/7675.
-
-   To prepare the PR:
-   ```sh
-   # Remove the RFC and ADR documents from the backport.
-   # We only maintain these on main to avoid confusion.
-   git rm -r docs/rfc docs/architecture
-
-   # Update absolute links to point to the backport.
-   go run ./scripts/linkpatch -recur -target v0.35.x -skip-path docs/DOCS_README.md,docs/README.md docs
-
-   # Create and push the PR.
-   git checkout -b update-docs-v035x
-   git commit -m "Update docs for v0.35.x backport branch." docs
-   git push -u origin update-docs-v035x
-   ```
-
-   Be sure to merge this PR before making other changes on the newly-created
-   backport branch.
-
-After doing these steps, go back to `main` and do the following:
-
-1. Tag `main` as the dev branch for the _next_ minor version release and push
-   it up to GitHub.
-   For example:
-   ```sh
-   git tag -a v0.36.0-dev -m "Development base for Tendermint v0.36."
-   git push origin v0.36.0-dev
-   ```
-
-2. Create a new workflow to run e2e nightlies for the new backport branch. (See
-   [e2e-nightly-main.yml][e2e] for an example.)
-
-3. Add a new section to the Mergify config (`.github/mergify.yml`) to enable the
-   backport bot to work on this branch, and add a corresponding `S:backport-to-v0.35.x`
-   [label](https://github.com/tendermint/tendermint/labels) so the bot can be triggered.
-
-4. Add a new section to the Dependabot config (`.github/dependabot.yml`) to
-   enable automatic update of Go dependencies on this branch. Copy and edit one
-   of the existing branch configurations to set the correct `target-branch`.
-
-[e2e]: https://github.com/tendermint/tendermint/blob/main/.github/workflows/e2e-nightly-main.yml
-
-## Release candidates
-
-Before creating an official release, especially a minor release, we may want to
-create a release candidate (RC) for our friends and partners to test out. We use
-git tags to create RCs, and we build them off of backport branches.
-
-Tags for RCs should follow the "standard" release naming conventions, with
-`-rcX` at the end (for example, `v0.35.0-rc0`).
-
-(Note that branches and tags _cannot_ have the same names, so it's important
-that these branches have distinct names from the tags/release names.)
-
-If this is the first RC for a minor release, you'll have to make a new backport
-branch (see above). Otherwise:
-
-1. Start from the backport branch (e.g. `v0.35.x`).
-2. Run the integration tests and the e2e nightlies
-   (which can be triggered from the Github UI;
-   e.g., https://github.com/tendermint/tendermint/actions/workflows/e2e-nightly-34x.yml).
-3. Prepare the changelog:
-   - Move the changes included in `CHANGELOG_PENDING.md` into `CHANGELOG.md`. Each RC should have
-     it's own changelog section. These will be squashed when the final candidate is released.
-   - Run `python ./scripts/linkify_changelog.py CHANGELOG.md` to add links for
-     all PRs
-   - Ensure that `UPGRADING.md` is up-to-date and includes notes on any breaking changes
-      or other upgrading flows.
-   - Bump TMVersionDefault version in  `version.go`
-   - Bump P2P and block protocol versions in  `version.go`, if necessary.
-     Check the changelog for breaking changes in these components.
-   - Bump ABCI protocol version in `version.go`, if necessary
-4. Open a PR with these changes against the backport branch.
-5. Once these changes have landed on the backport branch, be sure to pull them back down locally.
-6. Once you have the changes locally, create the new tag, specifying a name and a tag "message":
-   `git tag -a v0.35.0-rc0 -m "Release Candidate v0.35.0-rc0`
-7. Push the tag back up to origin:
-   `git push origin v0.35.0-rc0`
-   Now the tag should be available on the repo's releases page.
-8. Future RCs will continue to be built off of this branch.
-
-Note that this process should only be used for "true" RCs -- release candidates
-that, if successful, will be the next release. For more experimental "RCs,"
-create a new, short-lived branch and tag that instead.
-
-## Minor release
-
-This minor release process assumes that this release was preceded by release
-candidates. If there were no release candidates, begin by creating a backport
-branch, as described above.
-
-Before performing these steps, be sure the
-[Minor Release Checklist](#minor-release-checklist) has been completed.
-
-1. Start on the backport branch (e.g. `v0.35.x`)
-2. Run integration tests (`make test_integrations`) and the e2e nightlies.
-3. Prepare the release:
-   - "Squash" changes from the changelog entries for the RCs into a single entry,
-      and add all changes included in `CHANGELOG_PENDING.md`.
-      (Squashing includes both combining all entries, as well as removing or simplifying
-      any intra-RC changes. It may also help to alphabetize the entries by package name.)
-   - Run `python ./scripts/linkify_changelog.py CHANGELOG.md` to add links for
-     all PRs
-   - Ensure that `UPGRADING.md` is up-to-date and includes notes on any breaking changes
-      or other upgrading flows.
-   - Bump TMVersionDefault version in  `version.go`
-   - Bump P2P and block protocol versions in  `version.go`, if necessary
-   - Bump ABCI protocol version in `version.go`, if necessary
-4. Open a PR with these changes against the backport branch.
-5. Once these changes are on the backport branch, push a tag with prepared release details.
-   This will trigger the actual release `v0.35.0`.
-   - `git tag -a v0.35.0 -m 'Release v0.35.0'`
-   - `git push origin v0.35.0`
-6. Make sure that `main` is updated with the latest `CHANGELOG.md`, `CHANGELOG_PENDING.md`, and `UPGRADING.md`.
-7. Add the release to the documentation site generator config (see
-   [DOCS_README.md](./docs/DOCS_README.md) for more details). In summary:
-   - Start on branch `main`.
-   - Add a new line at the bottom of [`docs/versions`](./docs/versions) to
-     ensure the newest release is the default for the landing page.
-   - Add a new entry to `themeConfig.versions` in
-     [`docs/.vuepress/config.js`](./docs/.vuepress/config.js) to include the
-	 release in the dropdown versions menu.
-   - Commit these changes to `main` and backport them into the backport
-     branch for this release.
-
-## Patch release
-
-Patch releases are done differently from minor releases: They are built off of
-long-lived backport branches, rather than from main.  As non-breaking changes
-land on `main`, they should also be backported into these backport branches.
-
-Patch releases don't have release candidates by default, although any tricky
-changes may merit a release candidate.
-
-To create a patch release:
-
-1. Checkout the long-lived backport branch: `git checkout v0.35.x`
-2. Run integration tests (`make test_integrations`) and the nightlies.
-3. Check out a new branch and prepare the release:
-   - Copy `CHANGELOG_PENDING.md` to top of `CHANGELOG.md`
-   - Run `python ./scripts/linkify_changelog.py CHANGELOG.md` to add links for all issues
-   - Run `bash ./scripts/authors.sh` to get a list of authors since the latest release, and add the GitHub aliases of external contributors to the top of the CHANGELOG. To lookup an alias from an email, try `bash ./scripts/authors.sh <email>`
-   - Reset the `CHANGELOG_PENDING.md`
-   - Bump the TMDefaultVersion in `version.go`
-   - Bump the ABCI version number, if necessary.
-     (Note that ABCI follows semver, and that ABCI versions are the only versions
-     which can change during patch releases, and only field additions are valid patch changes.)
-4. Open a PR with these changes that will land them back on `v0.35.x`
-5. Once this change has landed on the backport branch, make sure to pull it locally, then push a tag.
-   - `git tag -a v0.35.1 -m 'Release v0.35.1'`
-   - `git push origin v0.35.1`
-6. Create a pull request back to main with the CHANGELOG & version changes from the latest release.
-   - Remove all `R:patch` labels from the pull requests that were included in the release.
-   - Do not merge the backport branch into main.
-
-## Minor Release Checklist
-
-The following set of steps are performed on all releases that increment the
-_minor_ version, e.g. v0.25 to v0.26. These steps ensure that Tendermint is well
-tested, stable, and suitable for adoption by the various diverse projects that
-rely on Tendermint.
-
-### Feature Freeze
-
-Ahead of any minor version release of Tendermint, the software enters 'Feature
-Freeze' for at least two weeks. A feature freeze means that _no_ new features
-are added to the code being prepared for release. No code changes should be made
-to the code being released that do not directly improve pressing issues of code
-quality. The following must not be merged during a feature freeze:
-
-* Refactors that are not related to specific bug fixes.
-* Dependency upgrades.
-* New test code that does not test a discovered regression.
-* New features of any kind.
-* Documentation or spec improvements that are not related to the newly developed
-  code.
-
-This period directly follows the creation of the [backport
-branch](#creating-a-backport-branch). The Tendermint team instead directs all
-attention to ensuring that the existing code is stable and reliable. Broken
-tests are fixed, flakey-tests are remedied, end-to-end test failures are
-thoroughly diagnosed and all efforts of the team are aimed at improving the
-quality of the code. During this period, the upgrade harness tests are run
-repeatedly and a variety of in-house testnets are run to ensure Tendermint
-functions at the scale it will be used by application developers and node
-operators.
-
-### Nightly End-To-End Tests
-
-The Tendermint team maintains [a set of end-to-end
-tests](https://github.com/tendermint/tendermint/blob/main/test/e2e/README.md#L1)
-that run each night on the latest commit of the project and on the code in the
-tip of each supported backport branch. These tests start a network of
-containerized Tendermint processes and run automated checks that the network
-functions as expected in both stable and unstable conditions. During the feature
-freeze, these tests are run nightly and must pass consistently for a release of
-Tendermint to be considered stable.
-
-### Upgrade Harness
-
-> TODO(williambanfield): Change to past tense and clarify this section once
-> upgrade harness is complete.
-
-The Tendermint team is creating an upgrade test harness to exercise the workflow
-of stopping an instance of Tendermint running one version of the software and
-starting up the same application running the next version. To support upgrade
-testing, we will add the ability to terminate the Tendermint process at specific
-pre-defined points in its execution so that we can verify upgrades work in a
-representative sample of stop conditions.
-
-### Large Scale Testnets
-
-The Tendermint end-to-end tests run a small network (~10s of nodes) to exercise
-basic consensus interactions. Real world deployments of Tendermint often have
-over a hundred nodes just in the validator set, with many others acting as full
-nodes and sentry nodes. To gain more assurance before a release, we will also
-run larger-scale test networks to shake out emergent behaviors at scale.
-
-Large-scale test networks are run on a set of virtual machines (VMs). Each VM is
-equipped with 4 Gigabytes of RAM and 2 CPU cores. The network runs a very simple
-key-value store application. The application adds artificial delays to different
-ABCI calls to simulate a slow application. Each testnet is briefly run with no
-load being generated to collect a baseline performance. Once baseline is
-captured, a consistent load is applied across the network. This load takes the
-form of 10% of the running nodes all receiving a consistent stream of two
-hundred transactions per minute each.
-
-During each test net, the following metrics are monitored and collected on each
-node:
-
-* Consensus rounds per height
-* Maximum connected peers, Minimum connected peers, Rate of change of peer connections
-* Memory resident set size
-* CPU utilization
-* Blocks produced per minute
-* Seconds for each step of consensus (Propose, Prevote, Precommit, Commit)
-* Latency to receive block proposals
-
-For these tests we intentionally target low-powered host machines (with low core
-counts and limited memory) to ensure we observe similar kinds of resource contention
-and limitation that real-world  deployments of Tendermint experience in production.
-
-#### 200 Node Testnet
-
-To test the stability and performance of Tendermint in a real world scenario,
-a 200 node test network is run. The network comprises 5 seed nodes, 100
-validators and 95 non-validating full nodes. All nodes begin by dialing
-a subset of the seed nodes to discover peers. The network is run for several
-days, with metrics being collected continuously. In cases of changes to performance
-critical systems, testnets of larger sizes should be considered.
-
-#### Rotating Node Testnet
-
-Real-world deployments of Tendermint frequently see new nodes arrive and old
-nodes exit the network. The rotating node testnet ensures that Tendermint is
-able to handle this reliably. In this test, a network with 10 validators and
-3 seed nodes is started. A rolling set of 25 full nodes are started and each
-connects to the network by dialing one of the seed nodes. Once the node is able
-to blocksync to the head of the chain and begins producing blocks using
-Tendermint consensus it is stopped. Once stopped, a new node is started and
-takes its place. This network is run for several days.
-
-#### Network Partition Testnet
-
-Tendermint is expected to recover from network partitions. A partition where no
-subset of the nodes is left with the super-majority of the stake is expected to
-stop making blocks. Upon alleviation of the partition, the network is expected
-to once again become fully connected and capable of producing blocks. The
-network partition testnet ensures that Tendermint is able to handle this
-reliably at scale. In this test, a network with 100 validators and 95 full
-nodes is started. All validators have equal stake. Once the network is
-producing blocks, a set of firewall rules is deployed to create a partitioned
-network with 50% of the stake on one side and 50% on the other. Once the
-network stops producing blocks, the firewall rules are removed and the nodes
-are monitored to ensure they reconnect and that the network again begins
-producing blocks.
-
-#### Absent Stake Testnet
-
-Tendermint networks often run with _some_ portion of the voting power offline.
-The absent stake testnet ensures that large networks are able to handle this
-reliably. A set of 150 validator nodes and three seed nodes is started. The set
-of 150 validators is configured to only possess a cumulative stake of 67% of
-the total stake. The remaining 33% of the stake is configured to belong to
-a validator that is never actually run in the test network. The network is run
-for multiple days, ensuring that it is able to produce blocks without issue.

STYLE_GUIDE.md

@@ -98,7 +98,7 @@ Sometimes it's necessary to rename libraries to avoid naming collisions or ambig
     * Make use of table driven testing where possible and not-cumbersome
         * [Inspiration](https://dave.cheney.net/2013/06/09/writing-table-driven-tests-in-go)
     * Make use of [assert](https://godoc.org/github.com/stretchr/testify/assert) and [require](https://godoc.org/github.com/stretchr/testify/require)
-* When using mocks, it is recommended to use Testify [mock] (<https://pkg.go.dev/github.com/stretchr/testify/mock>
+* When using mocks, it is recommended to use Testify [mock](<https://pkg.go.dev/github.com/stretchr/testify/mock>
  ) along with [Mockery](https://github.com/vektra/mockery) for autogeneration
 
 ## Errors

UPGRADING.md

@@ -1,14 +1,15 @@
 # Upgrading Tendermint Core
 
-This guide provides instructions for upgrading to specific versions of Tendermint Core.
+This guide provides instructions for upgrading to specific versions of
+Tendermint Core.
 
+## v0.34.24
 
-## v0.37 (Unreleased)
-
-This version requires a coordinated network upgrade. It alters the elements in the predigest of the `LastResultsHash` and thus
-all nodes must upgrade together (see #9175).
-
-NOTE: v0.35 was recalled and v0.36 was skipped
+Note that in [\#9724](https://github.com/tendermint/tendermint/pull/9724) we
+un-prettified the JSON output (i.e. removed all indentation) of the HTTP and
+WebSocket RPC for performance and subscription stability reasons. We recommend
+using a tool such as [jq](https://github.com/stedolan/jq) to obtain prettified
+output if you rely on that prettified output in some way.
 
 ## v0.34.20
 
@@ -23,7 +24,7 @@ and gas cost).
 Operators can enable the priority mempool by setting `mempool.version` to
 `"v1"` in the `config.toml`. For more technical details about the priority
 mempool, see [ADR 067: Mempool
-Refactor](https://github.com/tendermint/tendermint/blob/master/docs/architecture/adr-067-mempool-refactor.md).
+Refactor](https://github.com/tendermint/tendermint/blob/main/docs/architecture/adr-067-mempool-refactor.md).
 
 ## v0.34.0
 
@@ -31,7 +32,7 @@ Refactor](https://github.com/tendermint/tendermint/blob/master/docs/architecture
 This release is not compatible with previous blockchains due to changes to
 the encoding format (see "Protocol Buffers," below) and the block header (see "Blockchain Protocol").
 
-Note also that Tendermint 0.34 also requires Go 1.15 or higher.
+Note also that Tendermint 0.34 also requires Go 1.16 or higher.
 
 ### ABCI Changes
 
@@ -41,7 +42,7 @@ Note also that Tendermint 0.34 also requires Go 1.15 or higher.
   were added to support the new State Sync feature.
   Previously, syncing a new node to a preexisting network could take days; but with State Sync,
   new nodes are able to join a network in a matter of seconds.
-  Read [the spec](https://docs.tendermint.com/master/spec/abci/apps.html#state-sync)
+  Read [the spec](https://github.com/tendermint/tendermint/blob/v0.34.x/spec/abci/apps.md#state-sync)
   if you want to learn more about State Sync, or if you'd like your application to use it.
   (If you don't want to support State Sync in your application, you can just implement these new
   ABCI methods as no-ops, leaving them empty.)
@@ -57,7 +58,7 @@ Note also that Tendermint 0.34 also requires Go 1.15 or higher.
   Applications should be able to handle these evidence types
   (i.e., through slashing or other accountability measures).
 
-* The [`PublicKey` type](https://github.com/tendermint/tendermint/blob/master/proto/tendermint/crypto/keys.proto#L13-L15)
+* The [`PublicKey` type](https://github.com/tendermint/tendermint/blob/v0.34.x/proto/tendermint/crypto/keys.proto#L13-L15)
   (used in ABCI as part of `ValidatorUpdate`) now uses a `oneof` protobuf type.
   Note that since Tendermint only supports ed25519 validator keys, there's only one
   option in the `oneof`.  For more, see "Protocol Buffers," below.
@@ -72,12 +73,9 @@ directory. For more, see "Protobuf," below.
 
 ### Blockchain Protocol
 
-* `Header#LastResultsHash` previously was the root hash of a Merkle tree built from `ResponseDeliverTx(Code, Data)` responses.
-  As of 0.34,`Header#LastResultsHash` is now the root hash of a Merkle tree built from:
-    * `BeginBlock#Events`
-    * Root hash of a Merkle tree built from `ResponseDeliverTx(Code, Data,
-      GasWanted, GasUsed, Events)` responses
-    * `BeginBlock#Events`
+* `Header#LastResultsHash`, which is the root hash of a Merkle tree built from
+  `ResponseDeliverTx(Code, Data)` as of v0.34 also includes `GasWanted` and `GasUsed`
+  fields.
 
 * Merkle hashes of empty trees previously returned nothing, but now return the hash of an empty input,
   to conform with [RFC-6962](https://tools.ietf.org/html/rfc6962).
@@ -167,7 +165,7 @@ The `bech32` package has moved to the Cosmos SDK:
 ### CLI
 
 The `tendermint lite` command has been renamed to `tendermint light` and has a slightly different API.
-See [the docs](https://docs.tendermint.com/master/tendermint-core/light-client-protocol.html#http-proxy) for details.
+See [the docs](https://docs.tendermint.com/v0.33/tendermint-core/light-client-protocol.html#http-proxy) for details.
 
 ### Light Client
 
@@ -181,6 +179,7 @@ Other user-relevant changes include:
 * The `Verifier` was broken up into two pieces:
     * Core verification logic (pure `VerifyX` functions)
     * `Client` object, which represents the complete light client
+* The new light client stores headers and validator sets as `LightBlock`s
 * The RPC client can be found in the `/rpc` directory.
 * The HTTP(S) proxy is located in the `/proxy` directory.
 
@@ -322,7 +321,7 @@ Evidence Params has been changed to include duration.
 ### RPC Changes
 
 * `/validators` is now paginated (default: 30 vals per page)
-* `/block_results` response format updated [see RPC docs for details](https://docs.tendermint.com/master/rpc/#/Info/block_results)
+* `/block_results` response format updated [see RPC docs for details](https://docs.tendermint.com/v0.33/rpc/#/Info/block_results)
 * Event suffix has been removed from the ID in event responses
 * IDs are now integers not `json-client-XYZ`
 
@@ -441,7 +440,7 @@ the compilation tag:
 
 Use `cleveldb` tag instead of `gcc` to compile Tendermint with CLevelDB or
 use `make build_c` / `make install_c` (full instructions can be found at
-<https://tendermint.com/docs/introduction/install.html#compile-with-cleveldb-support>)
+<https://docs.tendermint.com/v0.33/introduction/install.html#compile-with-cleveldb-support>)
 
 ## v0.31.0
 
@@ -516,14 +515,14 @@ due to changes in how various data structures are hashed.
 Any implementations of Tendermint blockchain verification, including lite clients,
 will need to be updated. For specific details:
 
-* [Merkle tree](https://github.com/tendermint/spec/blob/master/spec/blockchain/encoding.md#merkle-trees)
-* [ConsensusParams](https://github.com/tendermint/spec/blob/master/spec/blockchain/state.md#consensusparams)
+* [Merkle tree](https://github.com/tendermint/tendermint/blob/v0.34.x/spec/blockchain/encoding.md#merkle-trees)
+* [ConsensusParams](https://github.com/tendermint/tendermint/blob/v0.34.x/spec/blockchain/state.md#consensusparams)
 
 There was also a small change to field ordering in the vote struct. Any
 implementations of an out-of-process validator (like a Key-Management Server)
 will need to be updated. For specific details:
 
-* [Vote](https://github.com/tendermint/spec/blob/master/spec/consensus/signing.md#votes)
+* [Vote](https://github.com/tendermint/tendermint/blob/v0.34.x/spec/consensus/signing.md#votes)
 
 Finally, the proposer selection algorithm continues to evolve. See the
 [work-in-progress

abci/README.md

@@ -19,7 +19,7 @@ To get up and running quickly, see the [getting started guide](../docs/app-dev/g
 
 A detailed description of the ABCI methods and message types is contained in:
 
-- [The main spec](https://github.com/tendermint/spec/blob/master/spec/abci/abci.md)
+- [The main spec](https://github.com/tendermint/tendermint/blob/v0.34.x/spec/abci/abci.md)
 - [A protobuf file](./types/types.proto)
 - [A Go interface](./types/application.go)
 

abci/cmd/abci-cli/abci-cli.go

@@ -16,6 +16,7 @@ import (
 
 	abcicli "github.com/tendermint/tendermint/abci/client"
 	"github.com/tendermint/tendermint/abci/example/code"
+	"github.com/tendermint/tendermint/abci/example/counter"
 	"github.com/tendermint/tendermint/abci/example/kvstore"
 	"github.com/tendermint/tendermint/abci/server"
 	servertest "github.com/tendermint/tendermint/abci/tests/server"
@@ -43,6 +44,9 @@ var (
 	flagHeight int
 	flagProve  bool
 
+	// counter
+	flagSerial bool
+
 	// kvstore
 	flagPersist string
 )
@@ -54,7 +58,9 @@ var RootCmd = &cobra.Command{
 	PersistentPreRunE: func(cmd *cobra.Command, args []string) error {
 
 		switch cmd.Use {
-		case "kvstore", "version":
+		case "counter", "kvstore": // for the examples apps, don't pre-run
+			return nil
+		case "version": // skip running for version command
 			return nil
 		}
 
@@ -129,6 +135,10 @@ func addQueryFlags() {
 		"whether or not to return a merkle proof of the query result")
 }
 
+func addCounterFlags() {
+	counterCmd.PersistentFlags().BoolVarP(&flagSerial, "serial", "", false, "enforce incrementing (serial) transactions")
+}
+
 func addKVStoreFlags() {
 	kvstoreCmd.PersistentFlags().StringVarP(&flagPersist, "persist", "", "", "directory to use for a database")
 }
@@ -148,6 +158,8 @@ func addCommands() {
 	RootCmd.AddCommand(queryCmd)
 
 	// examples
+	addCounterFlags()
+	RootCmd.AddCommand(counterCmd)
 	addKVStoreFlags()
 	RootCmd.AddCommand(kvstoreCmd)
 }
@@ -255,6 +267,14 @@ var queryCmd = &cobra.Command{
 	RunE:  cmdQuery,
 }
 
+var counterCmd = &cobra.Command{
+	Use:   "counter",
+	Short: "ABCI demo example",
+	Long:  "ABCI demo example",
+	Args:  cobra.ExactArgs(0),
+	RunE:  cmdCounter,
+}
+
 var kvstoreCmd = &cobra.Command{
 	Use:   "kvstore",
 	Short: "ABCI demo example",
@@ -605,6 +625,32 @@ func cmdQuery(cmd *cobra.Command, args []string) error {
 	return nil
 }
 
+func cmdCounter(cmd *cobra.Command, args []string) error {
+	app := counter.NewApplication(flagSerial)
+	logger := log.NewTMLogger(log.NewSyncWriter(os.Stdout))
+
+	// Start the listener
+	srv, err := server.NewServer(flagAddress, flagAbci, app)
+	if err != nil {
+		return err
+	}
+	srv.SetLogger(logger.With("module", "abci-server"))
+	if err := srv.Start(); err != nil {
+		return err
+	}
+
+	// Stop upon receiving SIGTERM or CTRL-C.
+	tmos.TrapSignal(logger, func() {
+		// Cleanup
+		if err := srv.Stop(); err != nil {
+			logger.Error("Error while stopping server", "err", err)
+		}
+	})
+
+	// Run forever.
+	select {}
+}
+
 func cmdKVStore(cmd *cobra.Command, args []string) error {
 	logger := log.NewTMLogger(log.NewSyncWriter(os.Stdout))
 

abci/example/counter/counter.go

@@ -0,0 +1,103 @@
+package counter
+
+import (
+	"encoding/binary"
+	"fmt"
+
+	"github.com/tendermint/tendermint/abci/example/code"
+	"github.com/tendermint/tendermint/abci/types"
+)
+
+type Application struct {
+	types.BaseApplication
+
+	hashCount int
+	txCount   int
+	serial    bool
+}
+
+func NewApplication(serial bool) *Application {
+	return &Application{serial: serial}
+}
+
+func (app *Application) Info(req types.RequestInfo) types.ResponseInfo {
+	return types.ResponseInfo{Data: fmt.Sprintf("{\"hashes\":%v,\"txs\":%v}", app.hashCount, app.txCount)}
+}
+
+func (app *Application) SetOption(req types.RequestSetOption) types.ResponseSetOption {
+	key, value := req.Key, req.Value
+	if key == "serial" && value == "on" {
+		app.serial = true
+	} else {
+		/*
+			TODO Panic and have the ABCI server pass an exception.
+			The client can call SetOptionSync() and get an `error`.
+			return types.ResponseSetOption{
+				Error: fmt.Sprintf("Unknown key (%s) or value (%s)", key, value),
+			}
+		*/
+		return types.ResponseSetOption{}
+	}
+
+	return types.ResponseSetOption{}
+}
+
+func (app *Application) DeliverTx(req types.RequestDeliverTx) types.ResponseDeliverTx {
+	if app.serial {
+		if len(req.Tx) > 8 {
+			return types.ResponseDeliverTx{
+				Code: code.CodeTypeEncodingError,
+				Log:  fmt.Sprintf("Max tx size is 8 bytes, got %d", len(req.Tx))}
+		}
+		tx8 := make([]byte, 8)
+		copy(tx8[len(tx8)-len(req.Tx):], req.Tx)
+		txValue := binary.BigEndian.Uint64(tx8)
+		if txValue != uint64(app.txCount) {
+			return types.ResponseDeliverTx{
+				Code: code.CodeTypeBadNonce,
+				Log:  fmt.Sprintf("Invalid nonce. Expected %v, got %v", app.txCount, txValue)}
+		}
+	}
+	app.txCount++
+	return types.ResponseDeliverTx{Code: code.CodeTypeOK}
+}
+
+func (app *Application) CheckTx(req types.RequestCheckTx) types.ResponseCheckTx {
+	if app.serial {
+		if len(req.Tx) > 8 {
+			return types.ResponseCheckTx{
+				Code: code.CodeTypeEncodingError,
+				Log:  fmt.Sprintf("Max tx size is 8 bytes, got %d", len(req.Tx))}
+		}
+		tx8 := make([]byte, 8)
+		copy(tx8[len(tx8)-len(req.Tx):], req.Tx)
+		txValue := binary.BigEndian.Uint64(tx8)
+		if txValue < uint64(app.txCount) {
+			return types.ResponseCheckTx{
+				Code: code.CodeTypeBadNonce,
+				Log:  fmt.Sprintf("Invalid nonce. Expected >= %v, got %v", app.txCount, txValue)}
+		}
+	}
+	return types.ResponseCheckTx{Code: code.CodeTypeOK}
+}
+
+func (app *Application) Commit() (resp types.ResponseCommit) {
+	app.hashCount++
+	if app.txCount == 0 {
+		return types.ResponseCommit{}
+	}
+	hash := make([]byte, 8)
+	binary.BigEndian.PutUint64(hash, uint64(app.txCount))
+	return types.ResponseCommit{Data: hash}
+}
+
+func (app *Application) Query(reqQuery types.RequestQuery) types.ResponseQuery {
+	switch reqQuery.Path {
+	case "hash":
+		return types.ResponseQuery{Value: []byte(fmt.Sprintf("%v", app.hashCount))}
+	case "tx":
+		return types.ResponseQuery{Value: []byte(fmt.Sprintf("%v", app.txCount))}
+	default:
+		return types.ResponseQuery{Log: fmt.Sprintf("Invalid query path. Expected hash or tx, got %v", reqQuery.Path)}
+	}
+}

abci/example/kvstore/kvstore_test.go

@@ -2,7 +2,7 @@ package kvstore
 
 import (
 	"fmt"
-	"io/ioutil"
+	"os"
 	"sort"
 	"testing"
 
@@ -71,7 +71,7 @@ func TestKVStoreKV(t *testing.T) {
 }
 
 func TestPersistentKVStoreKV(t *testing.T) {
-	dir, err := ioutil.TempDir("/tmp", "abci-kvstore-test") // TODO
+	dir, err := os.MkdirTemp("/tmp", "abci-kvstore-test") // TODO
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -87,7 +87,7 @@ func TestPersistentKVStoreKV(t *testing.T) {
 }
 
 func TestPersistentKVStoreInfo(t *testing.T) {
-	dir, err := ioutil.TempDir("/tmp", "abci-kvstore-test") // TODO
+	dir, err := os.MkdirTemp("/tmp", "abci-kvstore-test") // TODO
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -114,12 +114,11 @@ func TestPersistentKVStoreInfo(t *testing.T) {
 	if resInfo.LastBlockHeight != height {
 		t.Fatalf("expected height of %d, got %d", height, resInfo.LastBlockHeight)
 	}
-
 }
 
 // add a validator, remove a validator, update a validator
 func TestValUpdates(t *testing.T) {
-	dir, err := ioutil.TempDir("/tmp", "abci-kvstore-test") // TODO
+	dir, err := os.MkdirTemp("/tmp", "abci-kvstore-test") // TODO
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -162,7 +161,7 @@ func TestValUpdates(t *testing.T) {
 
 	makeApplyBlock(t, kvstore, 2, diff, tx1, tx2, tx3)
 
-	vals1 = append(vals[:nInit-2], vals[nInit+1]) // nolint: gocritic
+	vals1 = append(vals[:nInit-2], vals[nInit+1]) //nolint: gocritic
 	vals2 = kvstore.Validators()
 	valsEqual(t, vals1, vals2)
 
@@ -181,7 +180,6 @@ func TestValUpdates(t *testing.T) {
 	vals1 = append([]types.ValidatorUpdate{v1}, vals1[1:]...)
 	vals2 = kvstore.Validators()
 	valsEqual(t, vals1, vals2)
-
 }
 
 func makeApplyBlock(
@@ -189,7 +187,8 @@ func makeApplyBlock(
 	kvstore types.Application,
 	heightInt int,
 	diff []types.ValidatorUpdate,
-	txs ...[]byte) {
+	txs ...[]byte,
+) {
 	// make and apply block
 	height := int64(heightInt)
 	hash := []byte("foo")
@@ -207,7 +206,6 @@ func makeApplyBlock(
 	kvstore.Commit()
 
 	valsEqual(t, diff, resEndBlock.ValidatorUpdates)
-
 }
 
 // order doesn't matter

abci/server/server.go

@@ -2,9 +2,8 @@
 Package server is used to start a new ABCI server.
 
 It contains two server implementation:
- * gRPC server
- * socket server
-
+  - gRPC server
+  - socket server
 */
 package server
 

abci/tests/client_server_test.go

@@ -19,12 +19,9 @@ func TestClientServerNoAddrPrefix(t *testing.T) {
 	assert.NoError(t, err, "expected no error on NewServer")
 	err = server.Start()
 	assert.NoError(t, err, "expected no error on server.Start")
-	defer func() { _ = server.Stop() }()
 
 	client, err := abciclient.NewClient(addr, transport, true)
 	assert.NoError(t, err, "expected no error on NewClient")
 	err = client.Start()
 	assert.NoError(t, err, "expected no error on client.Start")
-
-	_ = client.Stop()
 }

abci/tests/test_app/app.go

@@ -0,0 +1,78 @@
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+
+	abcicli "github.com/tendermint/tendermint/abci/client"
+	"github.com/tendermint/tendermint/abci/types"
+	"github.com/tendermint/tendermint/libs/log"
+)
+
+func startClient(abciType string) abcicli.Client {
+	// Start client
+	client, err := abcicli.NewClient("tcp://127.0.0.1:26658", abciType, true)
+	if err != nil {
+		panic(err.Error())
+	}
+	logger := log.NewTMLogger(log.NewSyncWriter(os.Stdout))
+	client.SetLogger(logger.With("module", "abcicli"))
+	if err := client.Start(); err != nil {
+		panicf("connecting to abci_app: %v", err.Error())
+	}
+
+	return client
+}
+
+func setOption(client abcicli.Client, key, value string) {
+	_, err := client.SetOptionSync(types.RequestSetOption{Key: key, Value: value})
+	if err != nil {
+		panicf("setting %v=%v: \nerr: %v", key, value, err)
+	}
+}
+
+func commit(client abcicli.Client, hashExp []byte) {
+	res, err := client.CommitSync()
+	if err != nil {
+		panicf("client error: %v", err)
+	}
+	if !bytes.Equal(res.Data, hashExp) {
+		panicf("Commit hash was unexpected. Got %X expected %X", res.Data, hashExp)
+	}
+}
+
+func deliverTx(client abcicli.Client, txBytes []byte, codeExp uint32, dataExp []byte) {
+	res, err := client.DeliverTxSync(types.RequestDeliverTx{Tx: txBytes})
+	if err != nil {
+		panicf("client error: %v", err)
+	}
+	if res.Code != codeExp {
+		panicf("DeliverTx response code was unexpected. Got %v expected %v. Log: %v", res.Code, codeExp, res.Log)
+	}
+	if !bytes.Equal(res.Data, dataExp) {
+		panicf("DeliverTx response data was unexpected. Got %X expected %X", res.Data, dataExp)
+	}
+}
+
+/*func checkTx(client abcicli.Client, txBytes []byte, codeExp uint32, dataExp []byte) {
+	res, err := client.CheckTxSync(txBytes)
+	if err != nil {
+		panicf("client error: %v", err)
+	}
+	if res.IsErr() {
+		panicf("checking tx %X: %v\nlog: %v", txBytes, res.Log)
+	}
+	if res.Code != codeExp {
+		panicf("CheckTx response code was unexpected. Got %v expected %v. Log: %v",
+			res.Code, codeExp, res.Log)
+	}
+	if !bytes.Equal(res.Data, dataExp) {
+		panicf("CheckTx response data was unexpected. Got %X expected %X",
+			res.Data, dataExp)
+	}
+}*/
+
+func panicf(format string, a ...interface{}) {
+	panic(fmt.Sprintf(format, a...))
+}

abci/tests/test_app/main.go

@@ -0,0 +1,95 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"os/exec"
+	"time"
+
+	"github.com/tendermint/tendermint/abci/example/code"
+	"github.com/tendermint/tendermint/abci/types"
+)
+
+var abciType string
+
+func init() {
+	abciType = os.Getenv("ABCI")
+	if abciType == "" {
+		abciType = "socket"
+	}
+}
+
+func main() {
+	testCounter()
+}
+
+const (
+	maxABCIConnectTries = 10
+)
+
+func ensureABCIIsUp(typ string, n int) error {
+	var err error
+	cmdString := "abci-cli echo hello"
+	if typ == "grpc" {
+		cmdString = "abci-cli --abci grpc echo hello"
+	}
+
+	for i := 0; i < n; i++ {
+		cmd := exec.Command("bash", "-c", cmdString)
+		_, err = cmd.CombinedOutput()
+		if err == nil {
+			break
+		}
+		<-time.After(500 * time.Millisecond)
+	}
+	return err
+}
+
+func testCounter() {
+	abciApp := os.Getenv("ABCI_APP")
+	if abciApp == "" {
+		panic("No ABCI_APP specified")
+	}
+
+	fmt.Printf("Running %s test with abci=%s\n", abciApp, abciType)
+	subCommand := fmt.Sprintf("abci-cli %s", abciApp)
+	cmd := exec.Command("bash", "-c", subCommand)
+	cmd.Stdout = os.Stdout
+	if err := cmd.Start(); err != nil {
+		log.Fatalf("starting %q err: %v", abciApp, err)
+	}
+	defer func() {
+		if err := cmd.Process.Kill(); err != nil {
+			log.Printf("error on process kill: %v", err)
+		}
+		if err := cmd.Wait(); err != nil {
+			log.Printf("error while waiting for cmd to exit: %v", err)
+		}
+	}()
+
+	if err := ensureABCIIsUp(abciType, maxABCIConnectTries); err != nil {
+		log.Fatalf("echo failed: %v", err) //nolint:gocritic
+	}
+
+	client := startClient(abciType)
+	defer func() {
+		if err := client.Stop(); err != nil {
+			log.Printf("error trying client stop: %v", err)
+		}
+	}()
+
+	setOption(client, "serial", "on")
+	commit(client, nil)
+	deliverTx(client, []byte("abc"), code.CodeTypeBadNonce, nil)
+	commit(client, nil)
+	deliverTx(client, []byte{0x00}, types.CodeTypeOK, nil)
+	commit(client, []byte{0, 0, 0, 0, 0, 0, 0, 1})
+	deliverTx(client, []byte{0x00}, code.CodeTypeBadNonce, nil)
+	deliverTx(client, []byte{0x01}, types.CodeTypeOK, nil)
+	deliverTx(client, []byte{0x00, 0x02}, types.CodeTypeOK, nil)
+	deliverTx(client, []byte{0x00, 0x03}, types.CodeTypeOK, nil)
+	deliverTx(client, []byte{0x00, 0x00, 0x04}, types.CodeTypeOK, nil)
+	deliverTx(client, []byte{0x00, 0x00, 0x06}, code.CodeTypeBadNonce, nil)
+	commit(client, []byte{0, 0, 0, 0, 0, 0, 0, 5})
+}

abci/tests/test_app/test.sh

@@ -0,0 +1,28 @@
+#! /bin/bash
+set -e
+
+# These tests spawn the counter app and server by execing the ABCI_APP command and run some simple client tests against it
+
+# Get the directory of where this script is.
+export PATH="$GOBIN:$PATH"
+SOURCE="${BASH_SOURCE[0]}"
+while [ -h "$SOURCE" ] ; do SOURCE="$(readlink "$SOURCE")"; done
+DIR="$( cd -P "$( dirname "$SOURCE" )" && pwd )"
+
+# Change into that dir because we expect that.
+cd "$DIR"
+
+echo "RUN COUNTER OVER SOCKET"
+# test golang counter
+ABCI_APP="counter" go run -mod=readonly ./*.go
+echo "----------------------"
+
+
+echo "RUN COUNTER OVER GRPC"
+# test golang counter via grpc
+ABCI_APP="counter --abci=grpc" ABCI="grpc" go run -mod=readonly ./*.go
+echo "----------------------"
+
+# test nodejs counter
+# TODO: fix node app
+#ABCI_APP="node $GOPATH/src/github.com/tendermint/js-abci/example/app.js" go test -test.run TestCounter

abci/tests/test_cli/test.sh

@@ -37,6 +37,7 @@ function testExample() {
 }
 
 testExample 1 tests/test_cli/ex1.abci abci-cli kvstore
+testExample 2 tests/test_cli/ex2.abci abci-cli counter
 
 echo ""
 echo "PASS"

appveyor.yml

@@ -1,12 +1,12 @@
 version: 1.0.{build}
 configuration: Release
 platform:
-  - x64
-  - x86
+- x64
+- x86
 clone_folder: c:\go\path\src\github.com\tendermint\tendermint
 before_build:
-  - cmd: set GOPATH=%GOROOT%\path
-  - cmd: set PATH=%GOPATH%\bin;%PATH%
+- cmd: set GOPATH=%GOROOT%\path
+- cmd: set PATH=%GOPATH%\bin;%PATH%
 build_script:
-  - cmd: make test
+- cmd: make test
 test: off

behaviour/doc.go

@@ -0,0 +1,41 @@
+/*
+Package Behaviour provides a mechanism for reactors to report behaviour of peers.
+
+Instead of a reactor calling the switch directly it will call the behaviour module which will
+handle the stoping and marking peer as good on behalf of the reactor.
+
+There are four different behaviours a reactor can report.
+
+1. bad message
+
+	type badMessage struct {
+		explanation string
+	}
+
+# This message will request the peer be stopped for an error
+
+2. message out of order
+
+	type messageOutOfOrder struct {
+		explanation string
+	}
+
+# This message will request the peer be stopped for an error
+
+3. consesnsus Vote
+
+	type consensusVote struct {
+		explanation string
+	}
+
+# This message will request the peer be marked as good
+
+4. block part
+
+	type blockPart struct {
+		explanation string
+	}
+
+This message will request the peer be marked as good
+*/
+package behaviour

behaviour/peer_behaviour.go

@@ -0,0 +1,49 @@
+package behaviour
+
+import (
+	"github.com/tendermint/tendermint/p2p"
+)
+
+// PeerBehaviour is a struct describing a behaviour a peer performed.
+// `peerID` identifies the peer and reason characterizes the specific
+// behaviour performed by the peer.
+type PeerBehaviour struct {
+	peerID p2p.ID
+	reason interface{}
+}
+
+type badMessage struct {
+	explanation string
+}
+
+// BadMessage returns a badMessage PeerBehaviour.
+func BadMessage(peerID p2p.ID, explanation string) PeerBehaviour {
+	return PeerBehaviour{peerID: peerID, reason: badMessage{explanation}}
+}
+
+type messageOutOfOrder struct {
+	explanation string
+}
+
+// MessageOutOfOrder returns a messagOutOfOrder PeerBehaviour.
+func MessageOutOfOrder(peerID p2p.ID, explanation string) PeerBehaviour {
+	return PeerBehaviour{peerID: peerID, reason: messageOutOfOrder{explanation}}
+}
+
+type consensusVote struct {
+	explanation string
+}
+
+// ConsensusVote returns a consensusVote PeerBehaviour.
+func ConsensusVote(peerID p2p.ID, explanation string) PeerBehaviour {
+	return PeerBehaviour{peerID: peerID, reason: consensusVote{explanation}}
+}
+
+type blockPart struct {
+	explanation string
+}
+
+// BlockPart returns blockPart PeerBehaviour.
+func BlockPart(peerID p2p.ID, explanation string) PeerBehaviour {
+	return PeerBehaviour{peerID: peerID, reason: blockPart{explanation}}
+}

behaviour/reporter.go

@@ -0,0 +1,86 @@
+package behaviour
+
+import (
+	"errors"
+
+	tmsync "github.com/tendermint/tendermint/libs/sync"
+	"github.com/tendermint/tendermint/p2p"
+)
+
+// Reporter provides an interface for reactors to report the behaviour
+// of peers synchronously to other components.
+type Reporter interface {
+	Report(behaviour PeerBehaviour) error
+}
+
+// SwitchReporter reports peer behaviour to an internal Switch.
+type SwitchReporter struct {
+	sw *p2p.Switch
+}
+
+// NewSwitchReporter return a new SwitchReporter instance which wraps the Switch.
+func NewSwitchReporter(sw *p2p.Switch) *SwitchReporter {
+	return &SwitchReporter{
+		sw: sw,
+	}
+}
+
+// Report reports the behaviour of a peer to the Switch.
+func (spbr *SwitchReporter) Report(behaviour PeerBehaviour) error {
+	peer := spbr.sw.Peers().Get(behaviour.peerID)
+	if peer == nil {
+		return errors.New("peer not found")
+	}
+
+	switch reason := behaviour.reason.(type) {
+	case consensusVote, blockPart:
+		spbr.sw.MarkPeerAsGood(peer)
+	case badMessage:
+		spbr.sw.StopPeerForError(peer, reason.explanation)
+	case messageOutOfOrder:
+		spbr.sw.StopPeerForError(peer, reason.explanation)
+	default:
+		return errors.New("unknown reason reported")
+	}
+
+	return nil
+}
+
+// MockReporter is a concrete implementation of the Reporter
+// interface used in reactor tests to ensure reactors report the correct
+// behaviour in manufactured scenarios.
+type MockReporter struct {
+	mtx tmsync.RWMutex
+	pb  map[p2p.ID][]PeerBehaviour
+}
+
+// NewMockReporter returns a Reporter which records all reported
+// behaviours in memory.
+func NewMockReporter() *MockReporter {
+	return &MockReporter{
+		pb: map[p2p.ID][]PeerBehaviour{},
+	}
+}
+
+// Report stores the PeerBehaviour produced by the peer identified by peerID.
+func (mpbr *MockReporter) Report(behaviour PeerBehaviour) error {
+	mpbr.mtx.Lock()
+	defer mpbr.mtx.Unlock()
+	mpbr.pb[behaviour.peerID] = append(mpbr.pb[behaviour.peerID], behaviour)
+
+	return nil
+}
+
+// GetBehaviours returns all behaviours reported on the peer identified by peerID.
+func (mpbr *MockReporter) GetBehaviours(peerID p2p.ID) []PeerBehaviour {
+	mpbr.mtx.RLock()
+	defer mpbr.mtx.RUnlock()
+	if items, ok := mpbr.pb[peerID]; ok {
+		result := make([]PeerBehaviour, len(items))
+		copy(result, items)
+
+		return result
+	}
+
+	return []PeerBehaviour{}
+}

behaviour/reporter_test.go

@@ -0,0 +1,205 @@
+package behaviour_test
+
+import (
+	"sync"
+	"testing"
+
+	bh "github.com/tendermint/tendermint/behaviour"
+	"github.com/tendermint/tendermint/p2p"
+)
+
+// TestMockReporter tests the MockReporter's ability to store reported
+// peer behaviour in memory indexed by the peerID.
+func TestMockReporter(t *testing.T) {
+	var peerID p2p.ID = "MockPeer"
+	pr := bh.NewMockReporter()
+
+	behaviours := pr.GetBehaviours(peerID)
+	if len(behaviours) != 0 {
+		t.Error("Expected to have no behaviours reported")
+	}
+
+	badMessage := bh.BadMessage(peerID, "bad message")
+	if err := pr.Report(badMessage); err != nil {
+		t.Error(err)
+	}
+	behaviours = pr.GetBehaviours(peerID)
+	if len(behaviours) != 1 {
+		t.Error("Expected the peer have one reported behaviour")
+	}
+
+	if behaviours[0] != badMessage {
+		t.Error("Expected Bad Message to have been reported")
+	}
+}
+
+type scriptItem struct {
+	peerID    p2p.ID
+	behaviour bh.PeerBehaviour
+}
+
+// equalBehaviours returns true if a and b contain the same PeerBehaviours with
+// the same freequencies and otherwise false.
+func equalBehaviours(a []bh.PeerBehaviour, b []bh.PeerBehaviour) bool {
+	aHistogram := map[bh.PeerBehaviour]int{}
+	bHistogram := map[bh.PeerBehaviour]int{}
+
+	for _, behaviour := range a {
+		aHistogram[behaviour]++
+	}
+
+	for _, behaviour := range b {
+		bHistogram[behaviour]++
+	}
+
+	if len(aHistogram) != len(bHistogram) {
+		return false
+	}
+
+	for _, behaviour := range a {
+		if aHistogram[behaviour] != bHistogram[behaviour] {
+			return false
+		}
+	}
+
+	for _, behaviour := range b {
+		if bHistogram[behaviour] != aHistogram[behaviour] {
+			return false
+		}
+	}
+
+	return true
+}
+
+// TestEqualPeerBehaviours tests that equalBehaviours can tell that two slices
+// of peer behaviours can be compared for the behaviours they contain and the
+// freequencies that those behaviours occur.
+func TestEqualPeerBehaviours(t *testing.T) {
+	var (
+		peerID        p2p.ID = "MockPeer"
+		consensusVote        = bh.ConsensusVote(peerID, "voted")
+		blockPart            = bh.BlockPart(peerID, "blocked")
+		equals               = []struct {
+			left  []bh.PeerBehaviour
+			right []bh.PeerBehaviour
+		}{
+			// Empty sets
+			{[]bh.PeerBehaviour{}, []bh.PeerBehaviour{}},
+			// Single behaviours
+			{[]bh.PeerBehaviour{consensusVote}, []bh.PeerBehaviour{consensusVote}},
+			// Equal Frequencies
+			{[]bh.PeerBehaviour{consensusVote, consensusVote},
+				[]bh.PeerBehaviour{consensusVote, consensusVote}},
+			// Equal frequencies different orders
+			{[]bh.PeerBehaviour{consensusVote, blockPart},
+				[]bh.PeerBehaviour{blockPart, consensusVote}},
+		}
+		unequals = []struct {
+			left  []bh.PeerBehaviour
+			right []bh.PeerBehaviour
+		}{
+			// Comparing empty sets to non empty sets
+			{[]bh.PeerBehaviour{}, []bh.PeerBehaviour{consensusVote}},
+			// Different behaviours
+			{[]bh.PeerBehaviour{consensusVote}, []bh.PeerBehaviour{blockPart}},
+			// Same behaviour with different frequencies
+			{[]bh.PeerBehaviour{consensusVote},
+				[]bh.PeerBehaviour{consensusVote, consensusVote}},
+		}
+	)
+
+	for _, test := range equals {
+		if !equalBehaviours(test.left, test.right) {
+			t.Errorf("expected %#v and %#v to be equal", test.left, test.right)
+		}
+	}
+
+	for _, test := range unequals {
+		if equalBehaviours(test.left, test.right) {
+			t.Errorf("expected %#v and %#v to be unequal", test.left, test.right)
+		}
+	}
+}
+
+// TestPeerBehaviourConcurrency constructs a scenario in which
+// multiple goroutines are using the same MockReporter instance.
+// This test reproduces the conditions in which MockReporter will
+// be used within a Reactor `Receive` method tests to ensure thread safety.
+func TestMockPeerBehaviourReporterConcurrency(t *testing.T) {
+	var (
+		behaviourScript = []struct {
+			peerID     p2p.ID
+			behaviours []bh.PeerBehaviour
+		}{
+			{"1", []bh.PeerBehaviour{bh.ConsensusVote("1", "")}},
+			{"2", []bh.PeerBehaviour{bh.ConsensusVote("2", ""), bh.ConsensusVote("2", ""), bh.ConsensusVote("2", "")}},
+			{
+				"3",
+				[]bh.PeerBehaviour{bh.BlockPart("3", ""),
+					bh.ConsensusVote("3", ""),
+					bh.BlockPart("3", ""),
+					bh.ConsensusVote("3", "")}},
+			{
+				"4",
+				[]bh.PeerBehaviour{bh.ConsensusVote("4", ""),
+					bh.ConsensusVote("4", ""),
+					bh.ConsensusVote("4", ""),
+					bh.ConsensusVote("4", "")}},
+			{
+				"5",
+				[]bh.PeerBehaviour{bh.BlockPart("5", ""),
+					bh.ConsensusVote("5", ""),
+					bh.BlockPart("5", ""),
+					bh.ConsensusVote("5", "")}},
+		}
+	)
+
+	var receiveWg sync.WaitGroup
+	pr := bh.NewMockReporter()
+	scriptItems := make(chan scriptItem)
+	done := make(chan int)
+	numConsumers := 3
+	for i := 0; i < numConsumers; i++ {
+		receiveWg.Add(1)
+		go func() {
+			defer receiveWg.Done()
+			for {
+				select {
+				case pb := <-scriptItems:
+					if err := pr.Report(pb.behaviour); err != nil {
+						t.Error(err)
+					}
+				case <-done:
+					return
+				}
+			}
+		}()
+	}
+
+	var sendingWg sync.WaitGroup
+	sendingWg.Add(1)
+	go func() {
+		defer sendingWg.Done()
+		for _, item := range behaviourScript {
+			for _, reason := range item.behaviours {
+				scriptItems <- scriptItem{item.peerID, reason}
+			}
+		}
+	}()
+
+	sendingWg.Wait()
+
+	for i := 0; i < numConsumers; i++ {
+		done <- 1
+	}
+
+	receiveWg.Wait()
+
+	for _, items := range behaviourScript {
+		reported := pr.GetBehaviours(items.peerID)
+		if !equalBehaviours(reported, items.behaviours) {
+			t.Errorf("expected peer %s to have behaved \nExpected: %#v \nGot %#v \n",
+				items.peerID, items.behaviours, reported)
+		}
+	}
+}

blockchain/msgs.go

@@ -6,6 +6,7 @@ import (
 
 	"github.com/gogo/protobuf/proto"
 
+	"github.com/tendermint/tendermint/p2p"
 	bcproto "github.com/tendermint/tendermint/proto/tendermint/blockchain"
 	"github.com/tendermint/tendermint/types"
 )
@@ -19,58 +20,6 @@ const (
 		BlockResponseMessageFieldKeySize
 )
 
-// EncodeMsg encodes a Protobuf message
-func EncodeMsg(pb proto.Message) ([]byte, error) {
-	msg := bcproto.Message{}
-
-	switch pb := pb.(type) {
-	case *bcproto.BlockRequest:
-		msg.Sum = &bcproto.Message_BlockRequest{BlockRequest: pb}
-	case *bcproto.BlockResponse:
-		msg.Sum = &bcproto.Message_BlockResponse{BlockResponse: pb}
-	case *bcproto.NoBlockResponse:
-		msg.Sum = &bcproto.Message_NoBlockResponse{NoBlockResponse: pb}
-	case *bcproto.StatusRequest:
-		msg.Sum = &bcproto.Message_StatusRequest{StatusRequest: pb}
-	case *bcproto.StatusResponse:
-		msg.Sum = &bcproto.Message_StatusResponse{StatusResponse: pb}
-	default:
-		return nil, fmt.Errorf("unknown message type %T", pb)
-	}
-
-	bz, err := proto.Marshal(&msg)
-	if err != nil {
-		return nil, fmt.Errorf("unable to marshal %T: %w", pb, err)
-	}
-
-	return bz, nil
-}
-
-// DecodeMsg decodes a Protobuf message.
-func DecodeMsg(bz []byte) (proto.Message, error) {
-	pb := &bcproto.Message{}
-
-	err := proto.Unmarshal(bz, pb)
-	if err != nil {
-		return nil, err
-	}
-
-	switch msg := pb.Sum.(type) {
-	case *bcproto.Message_BlockRequest:
-		return msg.BlockRequest, nil
-	case *bcproto.Message_BlockResponse:
-		return msg.BlockResponse, nil
-	case *bcproto.Message_NoBlockResponse:
-		return msg.NoBlockResponse, nil
-	case *bcproto.Message_StatusRequest:
-		return msg.StatusRequest, nil
-	case *bcproto.Message_StatusResponse:
-		return msg.StatusResponse, nil
-	default:
-		return nil, fmt.Errorf("unknown message type %T", msg)
-	}
-}
-
 // ValidateMsg validates a message.
 func ValidateMsg(pb proto.Message) error {
 	if pb == nil {
@@ -108,3 +57,31 @@ func ValidateMsg(pb proto.Message) error {
 	}
 	return nil
 }
+
+// EncodeMsg encodes a Protobuf message
+//
+// Deprecated: Will be removed in v0.37.
+func EncodeMsg(pb proto.Message) ([]byte, error) {
+	if um, ok := pb.(p2p.Wrapper); ok {
+		pb = um.Wrap()
+	}
+	bz, err := proto.Marshal(pb)
+	if err != nil {
+		return nil, fmt.Errorf("unable to marshal %T: %w", pb, err)
+	}
+
+	return bz, nil
+}
+
+// DecodeMsg decodes a Protobuf message.
+//
+// Deprecated: Will be removed in v0.37.
+func DecodeMsg(bz []byte) (proto.Message, error) {
+	pb := &bcproto.Message{}
+
+	err := proto.Unmarshal(bz, pb)
+	if err != nil {
+		return nil, err
+	}
+	return pb.Unwrap()
+}

blockchain/msgs_test.go

@@ -78,7 +78,7 @@ func TestBcStatusResponseMessageValidateBasic(t *testing.T) {
 	}
 }
 
-// nolint:lll // ignore line length in tests
+//nolint:lll // ignore line length in tests
 func TestBlockchainMessageVectors(t *testing.T) {
 	block := types.MakeBlock(int64(3), []types.Tx{types.Tx("Hello World")}, nil, nil)
 	block.Version.Block = 11 // overwrite updated protocol version

blockchain/v0/pool.go

@@ -1,4 +1,4 @@
-package blockchain
+package v0
 
 import (
 	"errors"
@@ -32,6 +32,7 @@ const (
 	maxTotalRequesters        = 600
 	maxPendingRequests        = maxTotalRequesters
 	maxPendingRequestsPerPeer = 20
+	requestRetrySeconds       = 30
 
 	// Minimum recv rate to ensure we're receiving blocks from a peer fast
 	// enough. If a peer is not sending us data at at least that rate, we
@@ -410,6 +411,7 @@ func (pool *BlockPool) sendError(err error, peerID p2p.ID) {
 }
 
 // for debugging purposes
+//
 //nolint:unused
 func (pool *BlockPool) debug() string {
 	pool.mtx.Lock()
@@ -601,7 +603,7 @@ OUTER_LOOP:
 			}
 			peer = bpr.pool.pickIncrAvailablePeer(bpr.height)
 			if peer == nil {
-				// log.Info("No peers available", "height", height)
+				bpr.Logger.Debug("No peers currently available; will retry shortly", "height", bpr.height)
 				time.Sleep(requestIntervalMS * time.Millisecond)
 				continue PICK_PEER_LOOP
 			}
@@ -611,6 +613,7 @@ OUTER_LOOP:
 		bpr.peerID = peer.id
 		bpr.mtx.Unlock()
 
+		to := time.NewTimer(requestRetrySeconds * time.Second)
 		// Send request and wait.
 		bpr.pool.sendRequest(bpr.height, peer.id)
 	WAIT_LOOP:
@@ -623,6 +626,11 @@ OUTER_LOOP:
 				return
 			case <-bpr.Quit():
 				return
+			case <-to.C:
+				bpr.Logger.Debug("Retrying block request after timeout", "height", bpr.height, "peer", bpr.peerID)
+				// Simulate a redo
+				bpr.reset()
+				continue OUTER_LOOP
 			case peerID := <-bpr.redoCh:
 				if peerID == bpr.peerID {
 					bpr.reset()

blockchain/v0/pool_test.go

@@ -1,4 +1,4 @@
-package blockchain
+package v0
 
 import (
 	"fmt"

blockchain/v0/reactor.go

@@ -1,10 +1,13 @@
-package blockchain
+package v0
 
 import (
 	"fmt"
 	"reflect"
 	"time"
 
+	"github.com/gogo/protobuf/proto"
+
+	bc "github.com/tendermint/tendermint/blockchain"
 	"github.com/tendermint/tendermint/libs/log"
 	"github.com/tendermint/tendermint/p2p"
 	bcproto "github.com/tendermint/tendermint/proto/tendermint/blockchain"
@@ -44,8 +47,8 @@ func (e peerError) Error() string {
 	return fmt.Sprintf("error with peer %v: %s", e.peerID, e.err.Error())
 }
 
-// Reactor handles long-term catchup syncing.
-type Reactor struct {
+// BlockchainReactor handles long-term catchup syncing.
+type BlockchainReactor struct {
 	p2p.BaseReactor
 
 	// immutable
@@ -60,9 +63,9 @@ type Reactor struct {
 	errorsCh   <-chan peerError
 }
 
-// NewReactor returns new reactor instance.
-func NewReactor(state sm.State, blockExec *sm.BlockExecutor, store *store.BlockStore,
-	fastSync bool) *Reactor {
+// NewBlockchainReactor returns new reactor instance.
+func NewBlockchainReactor(state sm.State, blockExec *sm.BlockExecutor, store *store.BlockStore,
+	fastSync bool) *BlockchainReactor {
 
 	if state.LastBlockHeight != store.Height() {
 		panic(fmt.Sprintf("state (%v) and store (%v) height mismatch", state.LastBlockHeight,
@@ -80,7 +83,7 @@ func NewReactor(state sm.State, blockExec *sm.BlockExecutor, store *store.BlockS
 	}
 	pool := NewBlockPool(startHeight, requestsCh, errorsCh)
 
-	bcR := &Reactor{
+	bcR := &BlockchainReactor{
 		initialState: state,
 		blockExec:    blockExec,
 		store:        store,
@@ -89,18 +92,18 @@ func NewReactor(state sm.State, blockExec *sm.BlockExecutor, store *store.BlockS
 		requestsCh:   requestsCh,
 		errorsCh:     errorsCh,
 	}
-	bcR.BaseReactor = *p2p.NewBaseReactor("Reactor", bcR)
+	bcR.BaseReactor = *p2p.NewBaseReactor("BlockchainReactor", bcR)
 	return bcR
 }
 
 // SetLogger implements service.Service by setting the logger on reactor and pool.
-func (bcR *Reactor) SetLogger(l log.Logger) {
+func (bcR *BlockchainReactor) SetLogger(l log.Logger) {
 	bcR.BaseService.Logger = l
 	bcR.pool.Logger = l
 }
 
 // OnStart implements service.Service.
-func (bcR *Reactor) OnStart() error {
+func (bcR *BlockchainReactor) OnStart() error {
 	if bcR.fastSync {
 		err := bcR.pool.Start()
 		if err != nil {
@@ -112,7 +115,7 @@ func (bcR *Reactor) OnStart() error {
 }
 
 // SwitchToFastSync is called by the state sync reactor when switching to fast sync.
-func (bcR *Reactor) SwitchToFastSync(state sm.State) error {
+func (bcR *BlockchainReactor) SwitchToFastSync(state sm.State) error {
 	bcR.fastSync = true
 	bcR.initialState = state
 
@@ -126,7 +129,7 @@ func (bcR *Reactor) SwitchToFastSync(state sm.State) error {
 }
 
 // OnStop implements service.Service.
-func (bcR *Reactor) OnStop() {
+func (bcR *BlockchainReactor) OnStop() {
 	if bcR.fastSync {
 		if err := bcR.pool.Stop(); err != nil {
 			bcR.Logger.Error("Error stopping pool", "err", err)
@@ -135,29 +138,28 @@ func (bcR *Reactor) OnStop() {
 }
 
 // GetChannels implements Reactor
-func (bcR *Reactor) GetChannels() []*p2p.ChannelDescriptor {
+func (bcR *BlockchainReactor) GetChannels() []*p2p.ChannelDescriptor {
 	return []*p2p.ChannelDescriptor{
 		{
 			ID:                  BlockchainChannel,
 			Priority:            5,
 			SendQueueCapacity:   1000,
 			RecvBufferCapacity:  50 * 4096,
-			RecvMessageCapacity: MaxMsgSize,
+			RecvMessageCapacity: bc.MaxMsgSize,
+			MessageType:         &bcproto.Message{},
 		},
 	}
 }
 
 // AddPeer implements Reactor by sending our state to peer.
-func (bcR *Reactor) AddPeer(peer p2p.Peer) {
-	msgBytes, err := EncodeMsg(&bcproto.StatusResponse{
-		Base:   bcR.store.Base(),
-		Height: bcR.store.Height()})
-	if err != nil {
-		bcR.Logger.Error("could not convert msg to protobuf", "err", err)
-		return
-	}
-
-	peer.Send(BlockchainChannel, msgBytes)
+func (bcR *BlockchainReactor) AddPeer(peer p2p.Peer) {
+	p2p.SendEnvelopeShim(peer, p2p.Envelope{ //nolint: staticcheck
+		ChannelID: BlockchainChannel,
+		Message: &bcproto.StatusResponse{
+			Base:   bcR.store.Base(),
+			Height: bcR.store.Height(),
+		},
+	}, bcR.Logger)
 	// it's OK if send fails. will try later in poolRoutine
 
 	// peer is added to the pool once we receive the first
@@ -165,13 +167,13 @@ func (bcR *Reactor) AddPeer(peer p2p.Peer) {
 }
 
 // RemovePeer implements Reactor by removing peer from the pool.
-func (bcR *Reactor) RemovePeer(peer p2p.Peer, reason interface{}) {
+func (bcR *BlockchainReactor) RemovePeer(peer p2p.Peer, reason interface{}) {
 	bcR.pool.RemovePeer(peer.ID())
 }
 
 // respondToPeer loads a block and sends it to the requesting peer,
 // if we have it. Otherwise, we'll respond saying we don't have it.
-func (bcR *Reactor) respondToPeer(msg *bcproto.BlockRequest,
+func (bcR *BlockchainReactor) respondToPeer(msg *bcproto.BlockRequest,
 	src p2p.Peer) (queued bool) {
 
 	block := bcR.store.LoadBlock(msg.Height)
@@ -181,78 +183,76 @@ func (bcR *Reactor) respondToPeer(msg *bcproto.BlockRequest,
 			bcR.Logger.Error("could not convert msg to protobuf", "err", err)
 			return false
 		}
-
-		msgBytes, err := EncodeMsg(&bcproto.BlockResponse{Block: bl})
-		if err != nil {
-			bcR.Logger.Error("could not marshal msg", "err", err)
-			return false
-		}
-
-		return src.TrySend(BlockchainChannel, msgBytes)
+		return p2p.TrySendEnvelopeShim(src, p2p.Envelope{ //nolint: staticcheck
+			ChannelID: BlockchainChannel,
+			Message:   &bcproto.BlockResponse{Block: bl},
+		}, bcR.Logger)
 	}
 
-	bcR.Logger.Info("Peer asking for a block we don't have", "src", src, "height", msg.Height)
-
-	msgBytes, err := EncodeMsg(&bcproto.NoBlockResponse{Height: msg.Height})
-	if err != nil {
-		bcR.Logger.Error("could not convert msg to protobuf", "err", err)
-		return false
-	}
-
-	return src.TrySend(BlockchainChannel, msgBytes)
+	return p2p.TrySendEnvelopeShim(src, p2p.Envelope{ //nolint: staticcheck
+		ChannelID: BlockchainChannel,
+		Message:   &bcproto.NoBlockResponse{Height: msg.Height},
+	}, bcR.Logger)
 }
 
-// Receive implements Reactor by handling 4 types of messages (look below).
-func (bcR *Reactor) Receive(chID byte, src p2p.Peer, msgBytes []byte) {
-	msg, err := DecodeMsg(msgBytes)
-	if err != nil {
-		bcR.Logger.Error("Error decoding message", "src", src, "chId", chID, "err", err)
-		bcR.Switch.StopPeerForError(src, err)
+func (bcR *BlockchainReactor) ReceiveEnvelope(e p2p.Envelope) {
+	if err := bc.ValidateMsg(e.Message); err != nil {
+		bcR.Logger.Error("Peer sent us invalid msg", "peer", e.Src, "msg", e.Message, "err", err)
+		bcR.Switch.StopPeerForError(e.Src, err)
 		return
 	}
 
-	if err = ValidateMsg(msg); err != nil {
-		bcR.Logger.Error("Peer sent us invalid msg", "peer", src, "msg", msg, "err", err)
-		bcR.Switch.StopPeerForError(src, err)
-		return
-	}
+	bcR.Logger.Debug("Receive", "e.Src", e.Src, "chID", e.ChannelID, "msg", e.Message)
 
-	bcR.Logger.Debug("Receive", "src", src, "chID", chID, "msg", msg)
-
-	switch msg := msg.(type) {
+	switch msg := e.Message.(type) {
 	case *bcproto.BlockRequest:
-		bcR.respondToPeer(msg, src)
+		bcR.respondToPeer(msg, e.Src)
 	case *bcproto.BlockResponse:
 		bi, err := types.BlockFromProto(msg.Block)
 		if err != nil {
 			bcR.Logger.Error("Block content is invalid", "err", err)
 			return
 		}
-		bcR.pool.AddBlock(src.ID(), bi, len(msgBytes))
+		bcR.pool.AddBlock(e.Src.ID(), bi, msg.Block.Size())
 	case *bcproto.StatusRequest:
 		// Send peer our state.
-		msgBytes, err := EncodeMsg(&bcproto.StatusResponse{
-			Height: bcR.store.Height(),
-			Base:   bcR.store.Base(),
-		})
-		if err != nil {
-			bcR.Logger.Error("could not convert msg to protobut", "err", err)
-			return
-		}
-		src.TrySend(BlockchainChannel, msgBytes)
+		p2p.TrySendEnvelopeShim(e.Src, p2p.Envelope{ //nolint: staticcheck
+			ChannelID: BlockchainChannel,
+			Message: &bcproto.StatusResponse{
+				Height: bcR.store.Height(),
+				Base:   bcR.store.Base(),
+			},
+		}, bcR.Logger)
 	case *bcproto.StatusResponse:
 		// Got a peer status. Unverified.
-		bcR.pool.SetPeerRange(src.ID(), msg.Base, msg.Height)
+		bcR.pool.SetPeerRange(e.Src.ID(), msg.Base, msg.Height)
 	case *bcproto.NoBlockResponse:
-		bcR.Logger.Debug("Peer does not have requested block", "peer", src, "height", msg.Height)
+		bcR.Logger.Debug("Peer does not have requested block", "peer", e.Src, "height", msg.Height)
 	default:
 		bcR.Logger.Error(fmt.Sprintf("Unknown message type %v", reflect.TypeOf(msg)))
 	}
 }
 
+func (bcR *BlockchainReactor) Receive(chID byte, peer p2p.Peer, msgBytes []byte) {
+	msg := &bcproto.Message{}
+	err := proto.Unmarshal(msgBytes, msg)
+	if err != nil {
+		panic(err)
+	}
+	uw, err := msg.Unwrap()
+	if err != nil {
+		panic(err)
+	}
+	bcR.ReceiveEnvelope(p2p.Envelope{
+		ChannelID: chID,
+		Src:       peer,
+		Message:   uw,
+	})
+}
+
 // Handle messages from the poolReactor telling the reactor what to do.
 // NOTE: Don't sleep in the FOR_LOOP or otherwise slow it down!
-func (bcR *Reactor) poolRoutine(stateSynced bool) {
+func (bcR *BlockchainReactor) poolRoutine(stateSynced bool) {
 
 	trySyncTicker := time.NewTicker(trySyncIntervalMS * time.Millisecond)
 	defer trySyncTicker.Stop()
@@ -285,13 +285,10 @@ func (bcR *Reactor) poolRoutine(stateSynced bool) {
 				if peer == nil {
 					continue
 				}
-				msgBytes, err := EncodeMsg(&bcproto.BlockRequest{Height: request.Height})
-				if err != nil {
-					bcR.Logger.Error("could not convert msg to proto", "err", err)
-					continue
-				}
-
-				queued := peer.TrySend(BlockchainChannel, msgBytes)
+				queued := p2p.TrySendEnvelopeShim(peer, p2p.Envelope{ //nolint: staticcheck
+					ChannelID: BlockchainChannel,
+					Message:   &bcproto.BlockRequest{Height: request.Height},
+				}, bcR.Logger)
 				if !queued {
 					bcR.Logger.Debug("Send queue is full, drop block request", "peer", peer.ID(), "height", request.Height)
 				}
@@ -303,7 +300,7 @@ func (bcR *Reactor) poolRoutine(stateSynced bool) {
 
 			case <-statusUpdateTicker.C:
 				// ask for status updates
-				go bcR.BroadcastStatusRequest() // nolint: errcheck
+				go bcR.BroadcastStatusRequest() //nolint: errcheck
 
 			}
 		}
@@ -381,14 +378,14 @@ FOR_LOOP:
 				if peer != nil {
 					// NOTE: we've already removed the peer's request, but we
 					// still need to clean up the rest.
-					bcR.Switch.StopPeerForError(peer, fmt.Errorf("Reactor validation error: %v", err))
+					bcR.Switch.StopPeerForError(peer, fmt.Errorf("blockchainReactor validation error: %v", err))
 				}
 				peerID2 := bcR.pool.RedoRequest(second.Height)
 				peer2 := bcR.Switch.Peers().Get(peerID2)
 				if peer2 != nil && peer2 != peer {
 					// NOTE: we've already removed the peer's request, but we
 					// still need to clean up the rest.
-					bcR.Switch.StopPeerForError(peer2, fmt.Errorf("Reactor validation error: %v", err))
+					bcR.Switch.StopPeerForError(peer2, fmt.Errorf("blockchainReactor validation error: %v", err))
 				}
 				continue FOR_LOOP
 			}
@@ -423,14 +420,10 @@ FOR_LOOP:
 }
 
 // BroadcastStatusRequest broadcasts `BlockStore` base and height.
-func (bcR *Reactor) BroadcastStatusRequest() error {
-	bm, err := EncodeMsg(&bcproto.StatusRequest{})
-	if err != nil {
-		bcR.Logger.Error("could not convert msg to proto", "err", err)
-		return fmt.Errorf("could not convert msg to proto: %w", err)
-	}
-
-	bcR.Switch.Broadcast(BlockchainChannel, bm)
-
+func (bcR *BlockchainReactor) BroadcastStatusRequest() error {
+	bcR.Switch.BroadcastEnvelope(p2p.Envelope{
+		ChannelID: BlockchainChannel,
+		Message:   &bcproto.StatusRequest{},
+	})
 	return nil
 }

blockchain/v0/reactor_test.go

@@ -1,4 +1,4 @@
-package blockchain
+package v0
 
 import (
 	"fmt"
@@ -7,6 +7,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/gogo/protobuf/proto"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 
@@ -17,6 +18,7 @@ import (
 	"github.com/tendermint/tendermint/libs/log"
 	"github.com/tendermint/tendermint/mempool/mock"
 	"github.com/tendermint/tendermint/p2p"
+	bcproto "github.com/tendermint/tendermint/proto/tendermint/blockchain"
 	"github.com/tendermint/tendermint/proxy"
 	sm "github.com/tendermint/tendermint/state"
 	"github.com/tendermint/tendermint/store"
@@ -46,23 +48,23 @@ func randGenesisDoc(numValidators int, randPower bool, minPower int64) (*types.G
 	}, privValidators
 }
 
-type ReactorPair struct {
-	reactor *Reactor
+type BlockchainReactorPair struct {
+	reactor *BlockchainReactor
 	app     proxy.AppConns
 }
 
-func newReactor(
+func newBlockchainReactor(
 	logger log.Logger,
 	genDoc *types.GenesisDoc,
 	privVals []types.PrivValidator,
-	maxBlockHeight int64) ReactorPair {
+	maxBlockHeight int64) BlockchainReactorPair {
 	if len(privVals) != 1 {
 		panic("only support one validator")
 	}
 
 	app := &testApp{}
 	cc := proxy.NewLocalClientCreator(app)
-	proxyApp := proxy.NewAppConns(cc, proxy.NopMetrics())
+	proxyApp := proxy.NewAppConns(cc)
 	err := proxyApp.Start()
 	if err != nil {
 		panic(fmt.Errorf("error start app: %w", err))
@@ -70,7 +72,9 @@ func newReactor(
 
 	blockDB := dbm.NewMemDB()
 	stateDB := dbm.NewMemDB()
-	stateStore := sm.NewStore(stateDB)
+	stateStore := sm.NewStore(stateDB, sm.StoreOptions{
+		DiscardABCIResponses: false,
+	})
 	blockStore := store.NewBlockStore(blockDB)
 
 	state, err := stateStore.LoadFromDBOrGenesisDoc(genDoc)
@@ -78,12 +82,14 @@ func newReactor(
 		panic(fmt.Errorf("error constructing state from genesis file: %w", err))
 	}
 
-	// Make the Reactor itself.
+	// Make the BlockchainReactor itself.
 	// NOTE we have to create and commit the blocks first because
 	// pool.height is determined from the store.
 	fastSync := true
 	db := dbm.NewMemDB()
-	stateStore = sm.NewStore(db)
+	stateStore = sm.NewStore(db, sm.StoreOptions{
+		DiscardABCIResponses: false,
+	})
 	blockExec := sm.NewBlockExecutor(stateStore, log.TestingLogger(), proxyApp.Consensus(),
 		mock.Mempool{}, sm.EmptyEvidencePool{})
 	if err = stateStore.Save(state); err != nil {
@@ -125,10 +131,10 @@ func newReactor(
 		blockStore.SaveBlock(thisBlock, thisParts, lastCommit)
 	}
 
-	bcReactor := NewReactor(state.Copy(), blockExec, blockStore, fastSync)
+	bcReactor := NewBlockchainReactor(state.Copy(), blockExec, blockStore, fastSync)
 	bcReactor.SetLogger(logger.With("module", "blockchain"))
 
-	return ReactorPair{bcReactor, proxyApp}
+	return BlockchainReactorPair{bcReactor, proxyApp}
 }
 
 func TestNoBlockResponse(t *testing.T) {
@@ -138,10 +144,10 @@ func TestNoBlockResponse(t *testing.T) {
 
 	maxBlockHeight := int64(65)
 
-	reactorPairs := make([]ReactorPair, 2)
+	reactorPairs := make([]BlockchainReactorPair, 2)
 
-	reactorPairs[0] = newReactor(log.TestingLogger(), genDoc, privVals, maxBlockHeight)
-	reactorPairs[1] = newReactor(log.TestingLogger(), genDoc, privVals, 0)
+	reactorPairs[0] = newBlockchainReactor(log.TestingLogger(), genDoc, privVals, maxBlockHeight)
+	reactorPairs[1] = newBlockchainReactor(log.TestingLogger(), genDoc, privVals, 0)
 
 	p2p.MakeConnectedSwitches(config.P2P, 2, func(i int, s *p2p.Switch) *p2p.Switch {
 		s.AddReactor("BLOCKCHAIN", reactorPairs[i].reactor)
@@ -188,6 +194,25 @@ func TestNoBlockResponse(t *testing.T) {
 	}
 }
 
+func TestLegacyReactorReceiveBasic(t *testing.T) {
+	config = cfg.ResetTestRoot("blockchain_reactor_test")
+	defer os.RemoveAll(config.RootDir)
+	genDoc, privVals := randGenesisDoc(1, false, 30)
+	reactor := newBlockchainReactor(log.TestingLogger(), genDoc, privVals, 10).reactor
+	peer := p2p.CreateRandomPeer(false)
+
+	reactor.InitPeer(peer)
+	reactor.AddPeer(peer)
+	m := &bcproto.StatusRequest{}
+	wm := m.Wrap()
+	msg, err := proto.Marshal(wm)
+	assert.NoError(t, err)
+
+	assert.NotPanics(t, func() {
+		reactor.Receive(BlockchainChannel, peer, msg)
+	})
+}
+
 // NOTE: This is too hard to test without
 // an easy way to add test peer to switch
 // or without significant refactoring of the module.
@@ -202,7 +227,7 @@ func TestBadBlockStopsPeer(t *testing.T) {
 
 	// Other chain needs a different validator set
 	otherGenDoc, otherPrivVals := randGenesisDoc(1, false, 30)
-	otherChain := newReactor(log.TestingLogger(), otherGenDoc, otherPrivVals, maxBlockHeight)
+	otherChain := newBlockchainReactor(log.TestingLogger(), otherGenDoc, otherPrivVals, maxBlockHeight)
 
 	defer func() {
 		err := otherChain.reactor.Stop()
@@ -211,12 +236,12 @@ func TestBadBlockStopsPeer(t *testing.T) {
 		require.NoError(t, err)
 	}()
 
-	reactorPairs := make([]ReactorPair, 4)
+	reactorPairs := make([]BlockchainReactorPair, 4)
 
-	reactorPairs[0] = newReactor(log.TestingLogger(), genDoc, privVals, maxBlockHeight)
-	reactorPairs[1] = newReactor(log.TestingLogger(), genDoc, privVals, 0)
-	reactorPairs[2] = newReactor(log.TestingLogger(), genDoc, privVals, 0)
-	reactorPairs[3] = newReactor(log.TestingLogger(), genDoc, privVals, 0)
+	reactorPairs[0] = newBlockchainReactor(log.TestingLogger(), genDoc, privVals, maxBlockHeight)
+	reactorPairs[1] = newBlockchainReactor(log.TestingLogger(), genDoc, privVals, 0)
+	reactorPairs[2] = newBlockchainReactor(log.TestingLogger(), genDoc, privVals, 0)
+	reactorPairs[3] = newBlockchainReactor(log.TestingLogger(), genDoc, privVals, 0)
 
 	switches := p2p.MakeConnectedSwitches(config.P2P, 4, func(i int, s *p2p.Switch) *p2p.Switch {
 		s.AddReactor("BLOCKCHAIN", reactorPairs[i].reactor)
@@ -254,7 +279,7 @@ func TestBadBlockStopsPeer(t *testing.T) {
 	// race, but can't be easily avoided.
 	reactorPairs[3].reactor.store = otherChain.reactor.store
 
-	lastReactorPair := newReactor(log.TestingLogger(), genDoc, privVals, 0)
+	lastReactorPair := newBlockchainReactor(log.TestingLogger(), genDoc, privVals, 0)
 	reactorPairs = append(reactorPairs, lastReactorPair)
 
 	switches = append(switches, p2p.MakeConnectedSwitches(config.P2P, 1, func(i int, s *p2p.Switch) *p2p.Switch {

blockchain/v1/peer.go

@@ -0,0 +1,211 @@
+package v1
+
+import (
+	"fmt"
+	"math"
+	"time"
+
+	flow "github.com/tendermint/tendermint/libs/flowrate"
+	"github.com/tendermint/tendermint/libs/log"
+	"github.com/tendermint/tendermint/p2p"
+	"github.com/tendermint/tendermint/types"
+)
+
+//--------
+// Peer
+
+// BpPeerParams stores the peer parameters that are used when creating a peer.
+type BpPeerParams struct {
+	timeout     time.Duration
+	minRecvRate int64
+	sampleRate  time.Duration
+	windowSize  time.Duration
+}
+
+// BpPeer is the datastructure associated with a fast sync peer.
+type BpPeer struct {
+	logger log.Logger
+	ID     p2p.ID
+
+	Base                    int64                  // the peer reported base
+	Height                  int64                  // the peer reported height
+	NumPendingBlockRequests int                    // number of requests still waiting for block responses
+	blocks                  map[int64]*types.Block // blocks received or expected to be received from this peer
+	blockResponseTimer      *time.Timer
+	recvMonitor             *flow.Monitor
+	params                  *BpPeerParams // parameters for timer and monitor
+
+	onErr func(err error, peerID p2p.ID) // function to call on error
+}
+
+// NewBpPeer creates a new peer.
+func NewBpPeer(peerID p2p.ID, base int64, height int64,
+	onErr func(err error, peerID p2p.ID), params *BpPeerParams) *BpPeer {
+
+	if params == nil {
+		params = BpPeerDefaultParams()
+	}
+	return &BpPeer{
+		ID:     peerID,
+		Base:   base,
+		Height: height,
+		blocks: make(map[int64]*types.Block, maxRequestsPerPeer),
+		logger: log.NewNopLogger(),
+		onErr:  onErr,
+		params: params,
+	}
+}
+
+// String returns a string representation of a peer.
+func (peer *BpPeer) String() string {
+	return fmt.Sprintf("peer: %v height: %v pending: %v", peer.ID, peer.Height, peer.NumPendingBlockRequests)
+}
+
+// SetLogger sets the logger of the peer.
+func (peer *BpPeer) SetLogger(l log.Logger) {
+	peer.logger = l
+}
+
+// Cleanup performs cleanup of the peer, removes blocks, requests, stops timer and monitor.
+func (peer *BpPeer) Cleanup() {
+	if peer.blockResponseTimer != nil {
+		peer.blockResponseTimer.Stop()
+	}
+	if peer.NumPendingBlockRequests != 0 {
+		peer.logger.Info("peer with pending requests is being cleaned", "peer", peer.ID)
+	}
+	if len(peer.blocks)-peer.NumPendingBlockRequests != 0 {
+		peer.logger.Info("peer with pending blocks is being cleaned", "peer", peer.ID)
+	}
+	for h := range peer.blocks {
+		delete(peer.blocks, h)
+	}
+	peer.NumPendingBlockRequests = 0
+	peer.recvMonitor = nil
+}
+
+// BlockAtHeight returns the block at a given height if available and errMissingBlock otherwise.
+func (peer *BpPeer) BlockAtHeight(height int64) (*types.Block, error) {
+	block, ok := peer.blocks[height]
+	if !ok {
+		return nil, errMissingBlock
+	}
+	if block == nil {
+		return nil, errMissingBlock
+	}
+	return peer.blocks[height], nil
+}
+
+// AddBlock adds a block at peer level. Block must be non-nil and recvSize a positive integer
+// The peer must have a pending request for this block.
+func (peer *BpPeer) AddBlock(block *types.Block, recvSize int) error {
+	if block == nil || recvSize < 0 {
+		panic("bad parameters")
+	}
+	existingBlock, ok := peer.blocks[block.Height]
+	if !ok {
+		peer.logger.Error("unsolicited block", "blockHeight", block.Height, "peer", peer.ID)
+		return errMissingBlock
+	}
+	if existingBlock != nil {
+		peer.logger.Error("already have a block for height", "height", block.Height)
+		return errDuplicateBlock
+	}
+	if peer.NumPendingBlockRequests == 0 {
+		panic("peer does not have pending requests")
+	}
+	peer.blocks[block.Height] = block
+	peer.NumPendingBlockRequests--
+	if peer.NumPendingBlockRequests == 0 {
+		peer.stopMonitor()
+		peer.stopBlockResponseTimer()
+	} else {
+		peer.recvMonitor.Update(recvSize)
+		peer.resetBlockResponseTimer()
+	}
+	return nil
+}
+
+// RemoveBlock removes the block of given height
+func (peer *BpPeer) RemoveBlock(height int64) {
+	delete(peer.blocks, height)
+}
+
+// RequestSent records that a request was sent, and starts the peer timer and monitor if needed.
+func (peer *BpPeer) RequestSent(height int64) {
+	peer.blocks[height] = nil
+
+	if peer.NumPendingBlockRequests == 0 {
+		peer.startMonitor()
+		peer.resetBlockResponseTimer()
+	}
+	peer.NumPendingBlockRequests++
+}
+
+// CheckRate verifies that the response rate of the peer is acceptable (higher than the minimum allowed).
+func (peer *BpPeer) CheckRate() error {
+	if peer.NumPendingBlockRequests == 0 {
+		return nil
+	}
+	curRate := peer.recvMonitor.Status().CurRate
+	// curRate can be 0 on start
+	if curRate != 0 && curRate < peer.params.minRecvRate {
+		err := errSlowPeer
+		peer.logger.Error("SendTimeout", "peer", peer,
+			"reason", err,
+			"curRate", fmt.Sprintf("%d KB/s", curRate/1024),
+			"minRate", fmt.Sprintf("%d KB/s", peer.params.minRecvRate/1024))
+		return err
+	}
+	return nil
+}
+
+func (peer *BpPeer) onTimeout() {
+	peer.onErr(errNoPeerResponse, peer.ID)
+}
+
+func (peer *BpPeer) stopMonitor() {
+	peer.recvMonitor.Done()
+	peer.recvMonitor = nil
+}
+
+func (peer *BpPeer) startMonitor() {
+	peer.recvMonitor = flow.New(peer.params.sampleRate, peer.params.windowSize)
+	initialValue := float64(peer.params.minRecvRate) * math.E
+	peer.recvMonitor.SetREMA(initialValue)
+}
+
+func (peer *BpPeer) resetBlockResponseTimer() {
+	if peer.blockResponseTimer == nil {
+		peer.blockResponseTimer = time.AfterFunc(peer.params.timeout, peer.onTimeout)
+	} else {
+		peer.blockResponseTimer.Reset(peer.params.timeout)
+	}
+}
+
+func (peer *BpPeer) stopBlockResponseTimer() bool {
+	if peer.blockResponseTimer == nil {
+		return false
+	}
+	return peer.blockResponseTimer.Stop()
+}
+
+// BpPeerDefaultParams returns the default peer parameters.
+func BpPeerDefaultParams() *BpPeerParams {
+	return &BpPeerParams{
+		// Timeout for a peer to respond to a block request.
+		timeout: 15 * time.Second,
+
+		// Minimum recv rate to ensure we're receiving blocks from a peer fast
+		// enough. If a peer is not sending data at at least that rate, we
+		// consider them to have timedout and we disconnect.
+		//
+		// Assuming a DSL connection (not a good choice) 128 Kbps (upload) ~ 15 KB/s,
+		// sending data across atlantic ~ 7.5 KB/s.
+		minRecvRate: int64(7680),
+
+		// Monitor parameters
+		sampleRate: time.Second,
+		windowSize: 40 * time.Second,
+	}
+}

blockchain/v1/peer_test.go

@@ -0,0 +1,280 @@
+package v1
+
+import (
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/tendermint/tendermint/libs/log"
+	tmrand "github.com/tendermint/tendermint/libs/rand"
+	"github.com/tendermint/tendermint/p2p"
+	"github.com/tendermint/tendermint/types"
+)
+
+func TestPeerMonitor(t *testing.T) {
+	peer := NewBpPeer(
+		p2p.ID(tmrand.Str(12)), 0, 10,
+		func(err error, _ p2p.ID) {},
+		nil)
+	peer.SetLogger(log.TestingLogger())
+	peer.startMonitor()
+	assert.NotNil(t, peer.recvMonitor)
+	peer.stopMonitor()
+	assert.Nil(t, peer.recvMonitor)
+}
+
+func TestPeerResetBlockResponseTimer(t *testing.T) {
+	var (
+		numErrFuncCalls int        // number of calls to the errFunc
+		lastErr         error      // last generated error
+		peerTestMtx     sync.Mutex // modifications of ^^ variables are also done from timer handler goroutine
+	)
+	params := &BpPeerParams{timeout: 20 * time.Millisecond}
+
+	peer := NewBpPeer(
+		p2p.ID(tmrand.Str(12)), 0, 10,
+		func(err error, _ p2p.ID) {
+			peerTestMtx.Lock()
+			defer peerTestMtx.Unlock()
+			lastErr = err
+			numErrFuncCalls++
+		},
+		params)
+
+	peer.SetLogger(log.TestingLogger())
+	checkByStoppingPeerTimer(t, peer, false)
+
+	// initial reset call with peer having a nil timer
+	peer.resetBlockResponseTimer()
+	assert.NotNil(t, peer.blockResponseTimer)
+	// make sure timer is running and stop it
+	checkByStoppingPeerTimer(t, peer, true)
+
+	// reset with running timer
+	peer.resetBlockResponseTimer()
+	time.Sleep(5 * time.Millisecond)
+	peer.resetBlockResponseTimer()
+	assert.NotNil(t, peer.blockResponseTimer)
+
+	// let the timer expire and ...
+	time.Sleep(50 * time.Millisecond)
+	// ... check timer is not running
+	checkByStoppingPeerTimer(t, peer, false)
+
+	peerTestMtx.Lock()
+	// ... check errNoPeerResponse has been sent
+	assert.Equal(t, 1, numErrFuncCalls)
+	assert.Equal(t, lastErr, errNoPeerResponse)
+	peerTestMtx.Unlock()
+}
+
+func TestPeerRequestSent(t *testing.T) {
+	params := &BpPeerParams{timeout: 2 * time.Millisecond}
+
+	peer := NewBpPeer(
+		p2p.ID(tmrand.Str(12)), 0, 10,
+		func(err error, _ p2p.ID) {},
+		params)
+
+	peer.SetLogger(log.TestingLogger())
+
+	peer.RequestSent(1)
+	assert.NotNil(t, peer.recvMonitor)
+	assert.NotNil(t, peer.blockResponseTimer)
+	assert.Equal(t, 1, peer.NumPendingBlockRequests)
+
+	peer.RequestSent(1)
+	assert.NotNil(t, peer.recvMonitor)
+	assert.NotNil(t, peer.blockResponseTimer)
+	assert.Equal(t, 2, peer.NumPendingBlockRequests)
+}
+
+func TestPeerGetAndRemoveBlock(t *testing.T) {
+	peer := NewBpPeer(
+		p2p.ID(tmrand.Str(12)), 0, 100,
+		func(err error, _ p2p.ID) {},
+		nil)
+
+	// Change peer height
+	peer.Height = int64(10)
+	assert.Equal(t, int64(10), peer.Height)
+
+	// request some blocks and receive few of them
+	for i := 1; i <= 10; i++ {
+		peer.RequestSent(int64(i))
+		if i > 5 {
+			// only receive blocks 1..5
+			continue
+		}
+		_ = peer.AddBlock(makeSmallBlock(i), 10)
+	}
+
+	tests := []struct {
+		name         string
+		height       int64
+		wantErr      error
+		blockPresent bool
+	}{
+		{"no request", 100, errMissingBlock, false},
+		{"no block", 6, errMissingBlock, false},
+		{"block 1 present", 1, nil, true},
+		{"block max present", 5, nil, true},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			// try to get the block
+			b, err := peer.BlockAtHeight(tt.height)
+			assert.Equal(t, tt.wantErr, err)
+			assert.Equal(t, tt.blockPresent, b != nil)
+
+			// remove the block
+			peer.RemoveBlock(tt.height)
+			_, err = peer.BlockAtHeight(tt.height)
+			assert.Equal(t, errMissingBlock, err)
+		})
+	}
+}
+
+func TestPeerAddBlock(t *testing.T) {
+	peer := NewBpPeer(
+		p2p.ID(tmrand.Str(12)), 0, 100,
+		func(err error, _ p2p.ID) {},
+		nil)
+
+	// request some blocks, receive one
+	for i := 1; i <= 10; i++ {
+		peer.RequestSent(int64(i))
+		if i == 5 {
+			// receive block 5
+			_ = peer.AddBlock(makeSmallBlock(i), 10)
+		}
+	}
+
+	tests := []struct {
+		name         string
+		height       int64
+		wantErr      error
+		blockPresent bool
+	}{
+		{"no request", 50, errMissingBlock, false},
+		{"duplicate block", 5, errDuplicateBlock, true},
+		{"block 1 successfully received", 1, nil, true},
+		{"block max successfully received", 10, nil, true},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			// try to get the block
+			err := peer.AddBlock(makeSmallBlock(int(tt.height)), 10)
+			assert.Equal(t, tt.wantErr, err)
+			_, err = peer.BlockAtHeight(tt.height)
+			assert.Equal(t, tt.blockPresent, err == nil)
+		})
+	}
+}
+
+func TestPeerOnErrFuncCalledDueToExpiration(t *testing.T) {
+
+	params := &BpPeerParams{timeout: 10 * time.Millisecond}
+	var (
+		numErrFuncCalls int        // number of calls to the onErr function
+		lastErr         error      // last generated error
+		peerTestMtx     sync.Mutex // modifications of ^^ variables are also done from timer handler goroutine
+	)
+
+	peer := NewBpPeer(
+		p2p.ID(tmrand.Str(12)), 0, 10,
+		func(err error, _ p2p.ID) {
+			peerTestMtx.Lock()
+			defer peerTestMtx.Unlock()
+			lastErr = err
+			numErrFuncCalls++
+		},
+		params)
+
+	peer.SetLogger(log.TestingLogger())
+
+	peer.RequestSent(1)
+	time.Sleep(50 * time.Millisecond)
+	// timer should have expired by now, check that the on error function was called
+	peerTestMtx.Lock()
+	assert.Equal(t, 1, numErrFuncCalls)
+	assert.Equal(t, errNoPeerResponse, lastErr)
+	peerTestMtx.Unlock()
+}
+
+func TestPeerCheckRate(t *testing.T) {
+	params := &BpPeerParams{
+		timeout:     time.Second,
+		minRecvRate: int64(100), // 100 bytes/sec exponential moving average
+	}
+	peer := NewBpPeer(
+		p2p.ID(tmrand.Str(12)), 0, 10,
+		func(err error, _ p2p.ID) {},
+		params)
+	peer.SetLogger(log.TestingLogger())
+
+	require.Nil(t, peer.CheckRate())
+
+	for i := 0; i < 40; i++ {
+		peer.RequestSent(int64(i))
+	}
+
+	// monitor starts with a higher rEMA (~ 2*minRecvRate), wait for it to go down
+	time.Sleep(900 * time.Millisecond)
+
+	// normal peer - send a bit more than 100 bytes/sec, > 10 bytes/100msec, check peer is not considered slow
+	for i := 0; i < 10; i++ {
+		_ = peer.AddBlock(makeSmallBlock(i), 11)
+		time.Sleep(100 * time.Millisecond)
+		require.Nil(t, peer.CheckRate())
+	}
+
+	// slow peer - send a bit less than 10 bytes/100msec
+	for i := 10; i < 20; i++ {
+		_ = peer.AddBlock(makeSmallBlock(i), 9)
+		time.Sleep(100 * time.Millisecond)
+	}
+	// check peer is considered slow
+	assert.Equal(t, errSlowPeer, peer.CheckRate())
+}
+
+func TestPeerCleanup(t *testing.T) {
+	params := &BpPeerParams{timeout: 2 * time.Millisecond}
+
+	peer := NewBpPeer(
+		p2p.ID(tmrand.Str(12)), 0, 10,
+		func(err error, _ p2p.ID) {},
+		params)
+	peer.SetLogger(log.TestingLogger())
+
+	assert.Nil(t, peer.blockResponseTimer)
+	peer.RequestSent(1)
+	assert.NotNil(t, peer.blockResponseTimer)
+
+	peer.Cleanup()
+	checkByStoppingPeerTimer(t, peer, false)
+}
+
+// Check if peer timer is running or not (a running timer can be successfully stopped).
+// Note: stops the timer.
+func checkByStoppingPeerTimer(t *testing.T, peer *BpPeer, running bool) {
+	assert.NotPanics(t, func() {
+		stopped := peer.stopBlockResponseTimer()
+		if running {
+			assert.True(t, stopped)
+		} else {
+			assert.False(t, stopped)
+		}
+	})
+}
+
+func makeSmallBlock(height int) *types.Block {
+	return types.MakeBlock(int64(height), []types.Tx{types.Tx("foo")}, nil, nil)
+}

blockchain/v1/pool.go

@@ -0,0 +1,370 @@
+package v1
+
+import (
+	"sort"
+
+	"github.com/tendermint/tendermint/libs/log"
+	"github.com/tendermint/tendermint/p2p"
+	"github.com/tendermint/tendermint/types"
+)
+
+// BlockPool keeps track of the fast sync peers, block requests and block responses.
+type BlockPool struct {
+	logger log.Logger
+	// Set of peers that have sent status responses, with height bigger than pool.Height
+	peers map[p2p.ID]*BpPeer
+	// Set of block heights and the corresponding peers from where a block response is expected or has been received.
+	blocks map[int64]p2p.ID
+
+	plannedRequests   map[int64]struct{} // list of blocks to be assigned peers for blockRequest
+	nextRequestHeight int64              // next height to be added to plannedRequests
+
+	Height        int64 // height of next block to execute
+	MaxPeerHeight int64 // maximum height of all peers
+	toBcR         bcReactor
+}
+
+// NewBlockPool creates a new BlockPool.
+func NewBlockPool(height int64, toBcR bcReactor) *BlockPool {
+	return &BlockPool{
+		Height:            height,
+		MaxPeerHeight:     0,
+		peers:             make(map[p2p.ID]*BpPeer),
+		blocks:            make(map[int64]p2p.ID),
+		plannedRequests:   make(map[int64]struct{}),
+		nextRequestHeight: height,
+		toBcR:             toBcR,
+	}
+}
+
+// SetLogger sets the logger of the pool.
+func (pool *BlockPool) SetLogger(l log.Logger) {
+	pool.logger = l
+}
+
+// ReachedMaxHeight check if the pool has reached the maximum peer height.
+func (pool *BlockPool) ReachedMaxHeight() bool {
+	return pool.Height >= pool.MaxPeerHeight
+}
+
+func (pool *BlockPool) rescheduleRequest(peerID p2p.ID, height int64) {
+	pool.logger.Info("reschedule requests made to peer for height ", "peerID", peerID, "height", height)
+	pool.plannedRequests[height] = struct{}{}
+	delete(pool.blocks, height)
+	pool.peers[peerID].RemoveBlock(height)
+}
+
+// Updates the pool's max height. If no peers are left MaxPeerHeight is set to 0.
+func (pool *BlockPool) updateMaxPeerHeight() {
+	var newMax int64
+	for _, peer := range pool.peers {
+		peerHeight := peer.Height
+		if peerHeight > newMax {
+			newMax = peerHeight
+		}
+	}
+	pool.MaxPeerHeight = newMax
+}
+
+// UpdatePeer adds a new peer or updates an existing peer with a new base and height.
+// If a peer is short it is not added.
+func (pool *BlockPool) UpdatePeer(peerID p2p.ID, base int64, height int64) error {
+
+	peer := pool.peers[peerID]
+
+	if peer == nil {
+		if height < pool.Height {
+			pool.logger.Info("Peer height too small",
+				"peer", peerID, "height", height, "fsm_height", pool.Height)
+			return errPeerTooShort
+		}
+		// Add new peer.
+		peer = NewBpPeer(peerID, base, height, pool.toBcR.sendPeerError, nil)
+		peer.SetLogger(pool.logger.With("peer", peerID))
+		pool.peers[peerID] = peer
+		pool.logger.Info("added peer", "peerID", peerID, "base", base, "height", height, "num_peers", len(pool.peers))
+	} else {
+		// Check if peer is lowering its height. This is not allowed.
+		if height < peer.Height {
+			pool.RemovePeer(peerID, errPeerLowersItsHeight)
+			return errPeerLowersItsHeight
+		}
+		// Update existing peer.
+		peer.Base = base
+		peer.Height = height
+	}
+
+	// Update the pool's MaxPeerHeight if needed.
+	pool.updateMaxPeerHeight()
+
+	return nil
+}
+
+// Cleans and deletes the peer. Recomputes the max peer height.
+func (pool *BlockPool) deletePeer(peer *BpPeer) {
+	if peer == nil {
+		return
+	}
+	peer.Cleanup()
+	delete(pool.peers, peer.ID)
+
+	if peer.Height == pool.MaxPeerHeight {
+		pool.updateMaxPeerHeight()
+	}
+}
+
+// RemovePeer removes the blocks and requests from the peer, reschedules them and deletes the peer.
+func (pool *BlockPool) RemovePeer(peerID p2p.ID, err error) {
+	peer := pool.peers[peerID]
+	if peer == nil {
+		return
+	}
+	pool.logger.Info("removing peer", "peerID", peerID, "error", err)
+
+	// Reschedule the block requests made to the peer, or received and not processed yet.
+	// Note that some of the requests may be removed further down.
+	for h := range pool.peers[peerID].blocks {
+		pool.rescheduleRequest(peerID, h)
+	}
+
+	oldMaxPeerHeight := pool.MaxPeerHeight
+	// Delete the peer. This operation may result in the pool's MaxPeerHeight being lowered.
+	pool.deletePeer(peer)
+
+	// Check if the pool's MaxPeerHeight has been lowered.
+	// This may happen if the tallest peer has been removed.
+	if oldMaxPeerHeight > pool.MaxPeerHeight {
+		// Remove any planned requests for heights over the new MaxPeerHeight.
+		for h := range pool.plannedRequests {
+			if h > pool.MaxPeerHeight {
+				delete(pool.plannedRequests, h)
+			}
+		}
+		// Adjust the nextRequestHeight to the new max plus one.
+		if pool.nextRequestHeight > pool.MaxPeerHeight {
+			pool.nextRequestHeight = pool.MaxPeerHeight + 1
+		}
+	}
+}
+
+func (pool *BlockPool) removeShortPeers() {
+	for _, peer := range pool.peers {
+		if peer.Height < pool.Height {
+			pool.RemovePeer(peer.ID, nil)
+		}
+	}
+}
+
+func (pool *BlockPool) removeBadPeers() {
+	pool.removeShortPeers()
+	for _, peer := range pool.peers {
+		if err := peer.CheckRate(); err != nil {
+			pool.RemovePeer(peer.ID, err)
+			pool.toBcR.sendPeerError(err, peer.ID)
+		}
+	}
+}
+
+// MakeNextRequests creates more requests if the block pool is running low.
+func (pool *BlockPool) MakeNextRequests(maxNumRequests int) {
+	heights := pool.makeRequestBatch(maxNumRequests)
+	if len(heights) != 0 {
+		pool.logger.Info("makeNextRequests will make following requests",
+			"number", len(heights), "heights", heights)
+	}
+
+	for _, height := range heights {
+		h := int64(height)
+		if !pool.sendRequest(h) {
+			// If a good peer was not found for sending the request at height h then return,
+			// as it shouldn't be possible to find a peer for h+1.
+			return
+		}
+		delete(pool.plannedRequests, h)
+	}
+}
+
+// Makes a batch of requests sorted by height such that the block pool has up to maxNumRequests entries.
+func (pool *BlockPool) makeRequestBatch(maxNumRequests int) []int {
+	pool.removeBadPeers()
+	// At this point pool.requests may include heights for requests to be redone due to removal of peers:
+	// - peers timed out or were removed by switch
+	// - FSM timed out on waiting to advance the block execution due to missing blocks at h or h+1
+	// Determine the number of requests needed by subtracting the number of requests already made from the maximum
+	// allowed
+	numNeeded := maxNumRequests - len(pool.blocks)
+	for len(pool.plannedRequests) < numNeeded {
+		if pool.nextRequestHeight > pool.MaxPeerHeight {
+			break
+		}
+		pool.plannedRequests[pool.nextRequestHeight] = struct{}{}
+		pool.nextRequestHeight++
+	}
+
+	heights := make([]int, 0, len(pool.plannedRequests))
+	for k := range pool.plannedRequests {
+		heights = append(heights, int(k))
+	}
+	sort.Ints(heights)
+	return heights
+}
+
+func (pool *BlockPool) sendRequest(height int64) bool {
+	for _, peer := range pool.peers {
+		if peer.NumPendingBlockRequests >= maxRequestsPerPeer {
+			continue
+		}
+		if peer.Base > height || peer.Height < height {
+			continue
+		}
+
+		err := pool.toBcR.sendBlockRequest(peer.ID, height)
+		if err == errNilPeerForBlockRequest {
+			// Switch does not have this peer, remove it and continue to look for another peer.
+			pool.logger.Error("switch does not have peer..removing peer selected for height", "peer",
+				peer.ID, "height", height)
+			pool.RemovePeer(peer.ID, err)
+			continue
+		}
+
+		if err == errSendQueueFull {
+			pool.logger.Error("peer queue is full", "peer", peer.ID, "height", height)
+			continue
+		}
+
+		pool.logger.Info("assigned request to peer", "peer", peer.ID, "height", height)
+
+		pool.blocks[height] = peer.ID
+		peer.RequestSent(height)
+
+		return true
+	}
+	pool.logger.Error("could not find peer to send request for block at height", "height", height)
+	return false
+}
+
+// AddBlock validates that the block comes from the peer it was expected from and stores it in the 'blocks' map.
+func (pool *BlockPool) AddBlock(peerID p2p.ID, block *types.Block, blockSize int) error {
+	peer, ok := pool.peers[peerID]
+	if !ok {
+		pool.logger.Error("block from unknown peer", "height", block.Height, "peer", peerID)
+		return errBadDataFromPeer
+	}
+	if wantPeerID, ok := pool.blocks[block.Height]; ok && wantPeerID != peerID {
+		pool.logger.Error("block received from wrong peer", "height", block.Height,
+			"peer", peerID, "expected_peer", wantPeerID)
+		return errBadDataFromPeer
+	}
+
+	return peer.AddBlock(block, blockSize)
+}
+
+// BlockData stores the peer responsible to deliver a block and the actual block if delivered.
+type BlockData struct {
+	block *types.Block
+	peer  *BpPeer
+}
+
+// BlockAndPeerAtHeight retrieves the block and delivery peer at specified height.
+// Returns errMissingBlock if a block was not found
+func (pool *BlockPool) BlockAndPeerAtHeight(height int64) (bData *BlockData, err error) {
+	peerID := pool.blocks[height]
+	peer := pool.peers[peerID]
+	if peer == nil {
+		return nil, errMissingBlock
+	}
+
+	block, err := peer.BlockAtHeight(height)
+	if err != nil {
+		return nil, err
+	}
+
+	return &BlockData{peer: peer, block: block}, nil
+
+}
+
+// FirstTwoBlocksAndPeers returns the blocks and the delivery peers at pool's height H and H+1.
+func (pool *BlockPool) FirstTwoBlocksAndPeers() (first, second *BlockData, err error) {
+	first, err = pool.BlockAndPeerAtHeight(pool.Height)
+	second, err2 := pool.BlockAndPeerAtHeight(pool.Height + 1)
+	if err == nil {
+		err = err2
+	}
+	return
+}
+
+// InvalidateFirstTwoBlocks removes the peers that sent us the first two blocks, blocks are removed by RemovePeer().
+func (pool *BlockPool) InvalidateFirstTwoBlocks(err error) {
+	first, err1 := pool.BlockAndPeerAtHeight(pool.Height)
+	second, err2 := pool.BlockAndPeerAtHeight(pool.Height + 1)
+
+	if err1 == nil {
+		pool.RemovePeer(first.peer.ID, err)
+	}
+	if err2 == nil {
+		pool.RemovePeer(second.peer.ID, err)
+	}
+}
+
+// ProcessedCurrentHeightBlock performs cleanup after a block is processed. It removes block at pool height and
+// the peers that are now short.
+func (pool *BlockPool) ProcessedCurrentHeightBlock() {
+	peerID, peerOk := pool.blocks[pool.Height]
+	if peerOk {
+		pool.peers[peerID].RemoveBlock(pool.Height)
+	}
+	delete(pool.blocks, pool.Height)
+	pool.logger.Debug("removed block at height", "height", pool.Height)
+	pool.Height++
+	pool.removeShortPeers()
+}
+
+// RemovePeerAtCurrentHeights checks if a block at pool's height H exists and if not, it removes the
+// delivery peer and returns. If a block at height H exists then the check and peer removal is done for H+1.
+// This function is called when the FSM is not able to make progress for some time.
+// This happens if either the block H or H+1 have not been delivered.
+func (pool *BlockPool) RemovePeerAtCurrentHeights(err error) {
+	peerID := pool.blocks[pool.Height]
+	peer, ok := pool.peers[peerID]
+	if ok {
+		if _, err := peer.BlockAtHeight(pool.Height); err != nil {
+			pool.logger.Info("remove peer that hasn't sent block at pool.Height",
+				"peer", peerID, "height", pool.Height)
+			pool.RemovePeer(peerID, err)
+			return
+		}
+	}
+	peerID = pool.blocks[pool.Height+1]
+	peer, ok = pool.peers[peerID]
+	if ok {
+		if _, err := peer.BlockAtHeight(pool.Height + 1); err != nil {
+			pool.logger.Info("remove peer that hasn't sent block at pool.Height+1",
+				"peer", peerID, "height", pool.Height+1)
+			pool.RemovePeer(peerID, err)
+			return
+		}
+	}
+}
+
+// Cleanup performs pool and peer cleanup
+func (pool *BlockPool) Cleanup() {
+	for id, peer := range pool.peers {
+		peer.Cleanup()
+		delete(pool.peers, id)
+	}
+	pool.plannedRequests = make(map[int64]struct{})
+	pool.blocks = make(map[int64]p2p.ID)
+	pool.nextRequestHeight = 0
+	pool.Height = 0
+	pool.MaxPeerHeight = 0
+}
+
+// NumPeers returns the number of peers in the pool
+func (pool *BlockPool) NumPeers() int {
+	return len(pool.peers)
+}
+
+// NeedsBlocks returns true if more blocks are required.
+func (pool *BlockPool) NeedsBlocks() bool {
+	return len(pool.blocks) < maxNumRequests
+}

blockchain/v1/pool_test.go

@@ -0,0 +1,691 @@
+package v1
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+
+	"github.com/tendermint/tendermint/libs/log"
+	"github.com/tendermint/tendermint/p2p"
+	"github.com/tendermint/tendermint/types"
+)
+
+type testPeer struct {
+	id     p2p.ID
+	base   int64
+	height int64
+}
+
+type testBcR struct {
+	logger log.Logger
+}
+
+type testValues struct {
+	numRequestsSent int
+}
+
+var testResults testValues
+
+func resetPoolTestResults() {
+	testResults.numRequestsSent = 0
+}
+
+func (testR *testBcR) sendPeerError(err error, peerID p2p.ID) {
+}
+
+func (testR *testBcR) sendStatusRequest() {
+}
+
+func (testR *testBcR) sendBlockRequest(peerID p2p.ID, height int64) error {
+	testResults.numRequestsSent++
+	return nil
+}
+
+func (testR *testBcR) resetStateTimer(name string, timer **time.Timer, timeout time.Duration) {
+}
+
+func (testR *testBcR) switchToConsensus() {
+
+}
+
+func newTestBcR() *testBcR {
+	testBcR := &testBcR{logger: log.TestingLogger()}
+	return testBcR
+}
+
+type tPBlocks struct {
+	id     p2p.ID
+	create bool
+}
+
+// Makes a block pool with specified current height, list of peers, block requests and block responses
+func makeBlockPool(bcr *testBcR, height int64, peers []BpPeer, blocks map[int64]tPBlocks) *BlockPool {
+	bPool := NewBlockPool(height, bcr)
+	bPool.SetLogger(bcr.logger)
+
+	txs := []types.Tx{types.Tx("foo"), types.Tx("bar")}
+
+	var maxH int64
+	for _, p := range peers {
+		if p.Height > maxH {
+			maxH = p.Height
+		}
+		bPool.peers[p.ID] = NewBpPeer(p.ID, p.Base, p.Height, bcr.sendPeerError, nil)
+		bPool.peers[p.ID].SetLogger(bcr.logger)
+
+	}
+	bPool.MaxPeerHeight = maxH
+	for h, p := range blocks {
+		bPool.blocks[h] = p.id
+		bPool.peers[p.id].RequestSent(h)
+		if p.create {
+			// simulate that a block at height h has been received
+			_ = bPool.peers[p.id].AddBlock(types.MakeBlock(h, txs, nil, nil), 100)
+		}
+	}
+	return bPool
+}
+
+func assertPeerSetsEquivalent(t *testing.T, set1 map[p2p.ID]*BpPeer, set2 map[p2p.ID]*BpPeer) {
+	assert.Equal(t, len(set1), len(set2))
+	for peerID, peer1 := range set1 {
+		peer2 := set2[peerID]
+		assert.NotNil(t, peer2)
+		assert.Equal(t, peer1.NumPendingBlockRequests, peer2.NumPendingBlockRequests)
+		assert.Equal(t, peer1.Height, peer2.Height)
+		assert.Equal(t, peer1.Base, peer2.Base)
+		assert.Equal(t, len(peer1.blocks), len(peer2.blocks))
+		for h, block1 := range peer1.blocks {
+			block2 := peer2.blocks[h]
+			// block1 and block2 could be nil if a request was made but no block was received
+			assert.Equal(t, block1, block2)
+		}
+	}
+}
+
+func assertBlockPoolEquivalent(t *testing.T, poolWanted, pool *BlockPool) {
+	assert.Equal(t, poolWanted.blocks, pool.blocks)
+	assertPeerSetsEquivalent(t, poolWanted.peers, pool.peers)
+	assert.Equal(t, poolWanted.MaxPeerHeight, pool.MaxPeerHeight)
+	assert.Equal(t, poolWanted.Height, pool.Height)
+
+}
+
+func TestBlockPoolUpdatePeer(t *testing.T) {
+	testBcR := newTestBcR()
+
+	tests := []struct {
+		name       string
+		pool       *BlockPool
+		args       testPeer
+		poolWanted *BlockPool
+		errWanted  error
+	}{
+		{
+			name:       "add a first short peer",
+			pool:       makeBlockPool(testBcR, 100, []BpPeer{}, map[int64]tPBlocks{}),
+			args:       testPeer{"P1", 0, 50},
+			errWanted:  errPeerTooShort,
+			poolWanted: makeBlockPool(testBcR, 100, []BpPeer{}, map[int64]tPBlocks{}),
+		},
+		{
+			name:       "add a first good peer",
+			pool:       makeBlockPool(testBcR, 100, []BpPeer{}, map[int64]tPBlocks{}),
+			args:       testPeer{"P1", 0, 101},
+			poolWanted: makeBlockPool(testBcR, 100, []BpPeer{{ID: "P1", Height: 101}}, map[int64]tPBlocks{}),
+		},
+		{
+			name:       "add a first good peer with base",
+			pool:       makeBlockPool(testBcR, 100, []BpPeer{}, map[int64]tPBlocks{}),
+			args:       testPeer{"P1", 10, 101},
+			poolWanted: makeBlockPool(testBcR, 100, []BpPeer{{ID: "P1", Base: 10, Height: 101}}, map[int64]tPBlocks{}),
+		},
+		{
+			name:       "increase the height of P1 from 120 to 123",
+			pool:       makeBlockPool(testBcR, 100, []BpPeer{{ID: "P1", Height: 120}}, map[int64]tPBlocks{}),
+			args:       testPeer{"P1", 0, 123},
+			poolWanted: makeBlockPool(testBcR, 100, []BpPeer{{ID: "P1", Height: 123}}, map[int64]tPBlocks{}),
+		},
+		{
+			name:       "decrease the height of P1 from 120 to 110",
+			pool:       makeBlockPool(testBcR, 100, []BpPeer{{ID: "P1", Height: 120}}, map[int64]tPBlocks{}),
+			args:       testPeer{"P1", 0, 110},
+			errWanted:  errPeerLowersItsHeight,
+			poolWanted: makeBlockPool(testBcR, 100, []BpPeer{}, map[int64]tPBlocks{}),
+		},
+		{
+			name: "decrease the height of P1 from 105 to 102 with blocks",
+			pool: makeBlockPool(testBcR, 100, []BpPeer{{ID: "P1", Height: 105}},
+				map[int64]tPBlocks{
+					100: {"P1", true}, 101: {"P1", true}, 102: {"P1", true}}),
+			args:      testPeer{"P1", 0, 102},
+			errWanted: errPeerLowersItsHeight,
+			poolWanted: makeBlockPool(testBcR, 100, []BpPeer{},
+				map[int64]tPBlocks{}),
+		},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			pool := tt.pool
+			err := pool.UpdatePeer(tt.args.id, tt.args.base, tt.args.height)
+			assert.Equal(t, tt.errWanted, err)
+			assert.Equal(t, tt.poolWanted.blocks, tt.pool.blocks)
+			assertPeerSetsEquivalent(t, tt.poolWanted.peers, tt.pool.peers)
+			assert.Equal(t, tt.poolWanted.MaxPeerHeight, tt.pool.MaxPeerHeight)
+		})
+	}
+}
+
+func TestBlockPoolRemovePeer(t *testing.T) {
+	testBcR := newTestBcR()
+
+	type args struct {
+		peerID p2p.ID
+		err    error
+	}
+
+	tests := []struct {
+		name       string
+		pool       *BlockPool
+		args       args
+		poolWanted *BlockPool
+	}{
+		{
+			name:       "attempt to delete non-existing peer",
+			pool:       makeBlockPool(testBcR, 100, []BpPeer{{ID: "P1", Height: 120}}, map[int64]tPBlocks{}),
+			args:       args{"P99", nil},
+			poolWanted: makeBlockPool(testBcR, 100, []BpPeer{{ID: "P1", Height: 120}}, map[int64]tPBlocks{}),
+		},
+		{
+			name:       "delete the only peer without blocks",
+			pool:       makeBlockPool(testBcR, 100, []BpPeer{{ID: "P1", Height: 120}}, map[int64]tPBlocks{}),
+			args:       args{"P1", nil},
+			poolWanted: makeBlockPool(testBcR, 100, []BpPeer{}, map[int64]tPBlocks{}),
+		},
+		{
+			name: "delete the shortest of two peers without blocks",
+			pool: makeBlockPool(
+				testBcR,
+				100,
+				[]BpPeer{{ID: "P1", Height: 100}, {ID: "P2", Height: 120}},
+				map[int64]tPBlocks{}),
+			args:       args{"P1", nil},
+			poolWanted: makeBlockPool(testBcR, 100, []BpPeer{{ID: "P2", Height: 120}}, map[int64]tPBlocks{}),
+		},
+		{
+			name: "delete the tallest of two peers without blocks",
+			pool: makeBlockPool(
+				testBcR,
+				100,
+				[]BpPeer{{ID: "P1", Height: 100}, {ID: "P2", Height: 120}},
+				map[int64]tPBlocks{}),
+			args:       args{"P2", nil},
+			poolWanted: makeBlockPool(testBcR, 100, []BpPeer{{ID: "P1", Height: 100}}, map[int64]tPBlocks{}),
+		},
+		{
+			name: "delete the only peer with block requests sent and blocks received",
+			pool: makeBlockPool(testBcR, 100, []BpPeer{{ID: "P1", Height: 120}},
+				map[int64]tPBlocks{100: {"P1", true}, 101: {"P1", false}}),
+			args:       args{"P1", nil},
+			poolWanted: makeBlockPool(testBcR, 100, []BpPeer{}, map[int64]tPBlocks{}),
+		},
+		{
+			name: "delete the shortest of two peers with block requests sent and blocks received",
+			pool: makeBlockPool(testBcR, 100, []BpPeer{{ID: "P1", Height: 120}, {ID: "P2", Height: 200}},
+				map[int64]tPBlocks{100: {"P1", true}, 101: {"P1", false}}),
+			args:       args{"P1", nil},
+			poolWanted: makeBlockPool(testBcR, 100, []BpPeer{{ID: "P2", Height: 200}}, map[int64]tPBlocks{}),
+		},
+		{
+			name: "delete the tallest of two peers with block requests sent and blocks received",
+			pool: makeBlockPool(testBcR, 100, []BpPeer{{ID: "P1", Height: 120}, {ID: "P2", Height: 110}},
+				map[int64]tPBlocks{100: {"P1", true}, 101: {"P1", false}}),
+			args:       args{"P1", nil},
+			poolWanted: makeBlockPool(testBcR, 100, []BpPeer{{ID: "P2", Height: 110}}, map[int64]tPBlocks{}),
+		},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			tt.pool.RemovePeer(tt.args.peerID, tt.args.err)
+			assertBlockPoolEquivalent(t, tt.poolWanted, tt.pool)
+		})
+	}
+}
+
+func TestBlockPoolRemoveShortPeers(t *testing.T) {
+	testBcR := newTestBcR()
+
+	tests := []struct {
+		name       string
+		pool       *BlockPool
+		poolWanted *BlockPool
+	}{
+		{
+			name: "no short peers",
+			pool: makeBlockPool(testBcR, 100,
+				[]BpPeer{{ID: "P1", Height: 100}, {ID: "P2", Height: 110}, {ID: "P3", Height: 120}}, map[int64]tPBlocks{}),
+			poolWanted: makeBlockPool(testBcR, 100,
+				[]BpPeer{{ID: "P1", Height: 100}, {ID: "P2", Height: 110}, {ID: "P3", Height: 120}}, map[int64]tPBlocks{}),
+		},
+
+		{
+			name: "one short peer",
+			pool: makeBlockPool(testBcR, 100,
+				[]BpPeer{{ID: "P1", Height: 100}, {ID: "P2", Height: 90}, {ID: "P3", Height: 120}}, map[int64]tPBlocks{}),
+			poolWanted: makeBlockPool(testBcR, 100,
+				[]BpPeer{{ID: "P1", Height: 100}, {ID: "P3", Height: 120}}, map[int64]tPBlocks{}),
+		},
+
+		{
+			name: "all short peers",
+			pool: makeBlockPool(testBcR, 100,
+				[]BpPeer{{ID: "P1", Height: 90}, {ID: "P2", Height: 91}, {ID: "P3", Height: 92}}, map[int64]tPBlocks{}),
+			poolWanted: makeBlockPool(testBcR, 100, []BpPeer{}, map[int64]tPBlocks{}),
+		},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			pool := tt.pool
+			pool.removeShortPeers()
+			assertBlockPoolEquivalent(t, tt.poolWanted, tt.pool)
+		})
+	}
+}
+
+func TestBlockPoolSendRequestBatch(t *testing.T) {
+	type testPeerResult struct {
+		id                      p2p.ID
+		numPendingBlockRequests int
+	}
+
+	testBcR := newTestBcR()
+
+	tests := []struct {
+		name               string
+		pool               *BlockPool
+		maxRequestsPerPeer int
+		expRequests        map[int64]bool
+		expRequestsSent    int
+		expPeerResults     []testPeerResult
+	}{
+		{
+			name:               "one peer - send up to maxRequestsPerPeer block requests",
+			pool:               makeBlockPool(testBcR, 10, []BpPeer{{ID: "P1", Height: 100}}, map[int64]tPBlocks{}),
+			maxRequestsPerPeer: 2,
+			expRequests:        map[int64]bool{10: true, 11: true},
+			expRequestsSent:    2,
+			expPeerResults:     []testPeerResult{{id: "P1", numPendingBlockRequests: 2}},
+		},
+		{
+			name: "multiple peers - stops at gap between height and base",
+			pool: makeBlockPool(testBcR, 10, []BpPeer{
+				{ID: "P1", Base: 1, Height: 12},
+				{ID: "P2", Base: 15, Height: 100},
+			}, map[int64]tPBlocks{}),
+			maxRequestsPerPeer: 10,
+			expRequests:        map[int64]bool{10: true, 11: true, 12: true},
+			expRequestsSent:    3,
+			expPeerResults: []testPeerResult{
+				{id: "P1", numPendingBlockRequests: 3},
+				{id: "P2", numPendingBlockRequests: 0},
+			},
+		},
+		{
+			name: "n peers - send n*maxRequestsPerPeer block requests",
+			pool: makeBlockPool(
+				testBcR,
+				10,
+				[]BpPeer{{ID: "P1", Height: 100}, {ID: "P2", Height: 100}},
+				map[int64]tPBlocks{}),
+			maxRequestsPerPeer: 2,
+			expRequests:        map[int64]bool{10: true, 11: true},
+			expRequestsSent:    4,
+			expPeerResults: []testPeerResult{
+				{id: "P1", numPendingBlockRequests: 2},
+				{id: "P2", numPendingBlockRequests: 2}},
+		},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			resetPoolTestResults()
+
+			var pool = tt.pool
+			maxRequestsPerPeer = tt.maxRequestsPerPeer
+			pool.MakeNextRequests(10)
+
+			assert.Equal(t, tt.expRequestsSent, testResults.numRequestsSent)
+			for _, tPeer := range tt.expPeerResults {
+				var peer = pool.peers[tPeer.id]
+				assert.NotNil(t, peer)
+				assert.Equal(t, tPeer.numPendingBlockRequests, peer.NumPendingBlockRequests)
+			}
+		})
+	}
+}
+
+func TestBlockPoolAddBlock(t *testing.T) {
+	testBcR := newTestBcR()
+	txs := []types.Tx{types.Tx("foo"), types.Tx("bar")}
+
+	type args struct {
+		peerID    p2p.ID
+		block     *types.Block
+		blockSize int
+	}
+	tests := []struct {
+		name       string
+		pool       *BlockPool
+		args       args
+		poolWanted *BlockPool
+		errWanted  error
+	}{
+		{name: "block from unknown peer",
+			pool: makeBlockPool(testBcR, 10, []BpPeer{{ID: "P1", Height: 100}}, map[int64]tPBlocks{}),
+			args: args{
+				peerID:    "P2",
+				block:     types.MakeBlock(int64(10), txs, nil, nil),
+				blockSize: 100,
+			},
+			poolWanted: makeBlockPool(testBcR, 10, []BpPeer{{ID: "P1", Height: 100}}, map[int64]tPBlocks{}),
+			errWanted:  errBadDataFromPeer,
+		},
+		{name: "unexpected block 11 from known peer - waiting for 10",
+			pool: makeBlockPool(testBcR, 10,
+				[]BpPeer{{ID: "P1", Height: 100}},
+				map[int64]tPBlocks{10: {"P1", false}}),
+			args: args{
+				peerID:    "P1",
+				block:     types.MakeBlock(int64(11), txs, nil, nil),
+				blockSize: 100,
+			},
+			poolWanted: makeBlockPool(testBcR, 10,
+				[]BpPeer{{ID: "P1", Height: 100}},
+				map[int64]tPBlocks{10: {"P1", false}}),
+			errWanted: errMissingBlock,
+		},
+		{name: "unexpected block 10 from known peer - already have 10",
+			pool: makeBlockPool(testBcR, 10,
+				[]BpPeer{{ID: "P1", Height: 100}},
+				map[int64]tPBlocks{10: {"P1", true}, 11: {"P1", false}}),
+			args: args{
+				peerID:    "P1",
+				block:     types.MakeBlock(int64(10), txs, nil, nil),
+				blockSize: 100,
+			},
+			poolWanted: makeBlockPool(testBcR, 10,
+				[]BpPeer{{ID: "P1", Height: 100}},
+				map[int64]tPBlocks{10: {"P1", true}, 11: {"P1", false}}),
+			errWanted: errDuplicateBlock,
+		},
+		{name: "unexpected block 10 from known peer P2 - expected 10 to come from P1",
+			pool: makeBlockPool(testBcR, 10,
+				[]BpPeer{{ID: "P1", Height: 100}, {ID: "P2", Height: 100}},
+				map[int64]tPBlocks{10: {"P1", false}}),
+			args: args{
+				peerID:    "P2",
+				block:     types.MakeBlock(int64(10), txs, nil, nil),
+				blockSize: 100,
+			},
+			poolWanted: makeBlockPool(testBcR, 10,
+				[]BpPeer{{ID: "P1", Height: 100}, {ID: "P2", Height: 100}},
+				map[int64]tPBlocks{10: {"P1", false}}),
+			errWanted: errBadDataFromPeer,
+		},
+		{name: "expected block from known peer",
+			pool: makeBlockPool(testBcR, 10,
+				[]BpPeer{{ID: "P1", Height: 100}},
+				map[int64]tPBlocks{10: {"P1", false}}),
+			args: args{
+				peerID:    "P1",
+				block:     types.MakeBlock(int64(10), txs, nil, nil),
+				blockSize: 100,
+			},
+			poolWanted: makeBlockPool(testBcR, 10,
+				[]BpPeer{{ID: "P1", Height: 100}},
+				map[int64]tPBlocks{10: {"P1", true}}),
+			errWanted: nil,
+		},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			err := tt.pool.AddBlock(tt.args.peerID, tt.args.block, tt.args.blockSize)
+			assert.Equal(t, tt.errWanted, err)
+			assertBlockPoolEquivalent(t, tt.poolWanted, tt.pool)
+		})
+	}
+}
+
+func TestBlockPoolFirstTwoBlocksAndPeers(t *testing.T) {
+	testBcR := newTestBcR()
+
+	tests := []struct {
+		name         string
+		pool         *BlockPool
+		firstWanted  int64
+		secondWanted int64
+		errWanted    error
+	}{
+		{
+			name: "both blocks missing",
+			pool: makeBlockPool(testBcR, 10,
+				[]BpPeer{{ID: "P1", Height: 100}, {ID: "P2", Height: 100}},
+				map[int64]tPBlocks{15: {"P1", true}, 16: {"P2", true}}),
+			errWanted: errMissingBlock,
+		},
+		{
+			name: "second block missing",
+			pool: makeBlockPool(testBcR, 15,
+				[]BpPeer{{ID: "P1", Height: 100}, {ID: "P2", Height: 100}},
+				map[int64]tPBlocks{15: {"P1", true}, 18: {"P2", true}}),
+			firstWanted: 15,
+			errWanted:   errMissingBlock,
+		},
+		{
+			name: "first block missing",
+			pool: makeBlockPool(testBcR, 15,
+				[]BpPeer{{ID: "P1", Height: 100}, {ID: "P2", Height: 100}},
+				map[int64]tPBlocks{16: {"P2", true}, 18: {"P2", true}}),
+			secondWanted: 16,
+			errWanted:    errMissingBlock,
+		},
+		{
+			name: "both blocks present",
+			pool: makeBlockPool(testBcR, 10,
+				[]BpPeer{{ID: "P1", Height: 100}, {ID: "P2", Height: 100}},
+				map[int64]tPBlocks{10: {"P1", true}, 11: {"P2", true}}),
+			firstWanted:  10,
+			secondWanted: 11,
+		},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			pool := tt.pool
+			gotFirst, gotSecond, err := pool.FirstTwoBlocksAndPeers()
+			assert.Equal(t, tt.errWanted, err)
+
+			if tt.firstWanted != 0 {
+				peer := pool.blocks[tt.firstWanted]
+				block := pool.peers[peer].blocks[tt.firstWanted]
+				assert.Equal(t, block, gotFirst.block,
+					"BlockPool.FirstTwoBlocksAndPeers() gotFirst = %v, want %v",
+					tt.firstWanted, gotFirst.block.Height)
+			}
+
+			if tt.secondWanted != 0 {
+				peer := pool.blocks[tt.secondWanted]
+				block := pool.peers[peer].blocks[tt.secondWanted]
+				assert.Equal(t, block, gotSecond.block,
+					"BlockPool.FirstTwoBlocksAndPeers() gotFirst = %v, want %v",
+					tt.secondWanted, gotSecond.block.Height)
+			}
+		})
+	}
+}
+
+func TestBlockPoolInvalidateFirstTwoBlocks(t *testing.T) {
+	testBcR := newTestBcR()
+
+	tests := []struct {
+		name       string
+		pool       *BlockPool
+		poolWanted *BlockPool
+	}{
+		{
+			name: "both blocks missing",
+			pool: makeBlockPool(testBcR, 10,
+				[]BpPeer{{ID: "P1", Height: 100}, {ID: "P2", Height: 100}},
+				map[int64]tPBlocks{15: {"P1", true}, 16: {"P2", true}}),
+			poolWanted: makeBlockPool(testBcR, 10,
+				[]BpPeer{{ID: "P1", Height: 100}, {ID: "P2", Height: 100}},
+				map[int64]tPBlocks{15: {"P1", true}, 16: {"P2", true}}),
+		},
+		{
+			name: "second block missing",
+			pool: makeBlockPool(testBcR, 15,
+				[]BpPeer{{ID: "P1", Height: 100}, {ID: "P2", Height: 100}},
+				map[int64]tPBlocks{15: {"P1", true}, 18: {"P2", true}}),
+			poolWanted: makeBlockPool(testBcR, 15,
+				[]BpPeer{{ID: "P2", Height: 100}},
+				map[int64]tPBlocks{18: {"P2", true}}),
+		},
+		{
+			name: "first block missing",
+			pool: makeBlockPool(testBcR, 15,
+				[]BpPeer{{ID: "P1", Height: 100}, {ID: "P2", Height: 100}},
+				map[int64]tPBlocks{18: {"P1", true}, 16: {"P2", true}}),
+			poolWanted: makeBlockPool(testBcR, 15,
+				[]BpPeer{{ID: "P1", Height: 100}},
+				map[int64]tPBlocks{18: {"P1", true}}),
+		},
+		{
+			name: "both blocks present",
+			pool: makeBlockPool(testBcR, 10,
+				[]BpPeer{{ID: "P1", Height: 100}, {ID: "P2", Height: 100}},
+				map[int64]tPBlocks{10: {"P1", true}, 11: {"P2", true}}),
+			poolWanted: makeBlockPool(testBcR, 10,
+				[]BpPeer{},
+				map[int64]tPBlocks{}),
+		},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			tt.pool.InvalidateFirstTwoBlocks(errNoPeerResponse)
+			assertBlockPoolEquivalent(t, tt.poolWanted, tt.pool)
+		})
+	}
+}
+
+func TestProcessedCurrentHeightBlock(t *testing.T) {
+	testBcR := newTestBcR()
+
+	tests := []struct {
+		name       string
+		pool       *BlockPool
+		poolWanted *BlockPool
+	}{
+		{
+			name: "one peer",
+			pool: makeBlockPool(testBcR, 100, []BpPeer{{ID: "P1", Height: 120}},
+				map[int64]tPBlocks{100: {"P1", true}, 101: {"P1", true}}),
+			poolWanted: makeBlockPool(testBcR, 101, []BpPeer{{ID: "P1", Height: 120}},
+				map[int64]tPBlocks{101: {"P1", true}}),
+		},
+		{
+			name: "multiple peers",
+			pool: makeBlockPool(testBcR, 100,
+				[]BpPeer{{ID: "P1", Height: 120}, {ID: "P2", Height: 120}, {ID: "P3", Height: 130}},
+				map[int64]tPBlocks{
+					100: {"P1", true}, 104: {"P1", true}, 105: {"P1", false},
+					101: {"P2", true}, 103: {"P2", false},
+					102: {"P3", true}, 106: {"P3", true}}),
+			poolWanted: makeBlockPool(testBcR, 101,
+				[]BpPeer{{ID: "P1", Height: 120}, {ID: "P2", Height: 120}, {ID: "P3", Height: 130}},
+				map[int64]tPBlocks{
+					104: {"P1", true}, 105: {"P1", false},
+					101: {"P2", true}, 103: {"P2", false},
+					102: {"P3", true}, 106: {"P3", true}}),
+		},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			tt.pool.ProcessedCurrentHeightBlock()
+			assertBlockPoolEquivalent(t, tt.poolWanted, tt.pool)
+		})
+	}
+}
+
+func TestRemovePeerAtCurrentHeight(t *testing.T) {
+	testBcR := newTestBcR()
+
+	tests := []struct {
+		name       string
+		pool       *BlockPool
+		poolWanted *BlockPool
+	}{
+		{
+			name: "one peer, remove peer for block at H",
+			pool: makeBlockPool(testBcR, 100, []BpPeer{{ID: "P1", Height: 120}},
+				map[int64]tPBlocks{100: {"P1", false}, 101: {"P1", true}}),
+			poolWanted: makeBlockPool(testBcR, 100, []BpPeer{}, map[int64]tPBlocks{}),
+		},
+		{
+			name: "one peer, remove peer for block at H+1",
+			pool: makeBlockPool(testBcR, 100, []BpPeer{{ID: "P1", Height: 120}},
+				map[int64]tPBlocks{100: {"P1", true}, 101: {"P1", false}}),
+			poolWanted: makeBlockPool(testBcR, 100, []BpPeer{}, map[int64]tPBlocks{}),
+		},
+		{
+			name: "multiple peers, remove peer for block at H",
+			pool: makeBlockPool(testBcR, 100,
+				[]BpPeer{{ID: "P1", Height: 120}, {ID: "P2", Height: 120}, {ID: "P3", Height: 130}},
+				map[int64]tPBlocks{
+					100: {"P1", false}, 104: {"P1", true}, 105: {"P1", false},
+					101: {"P2", true}, 103: {"P2", false},
+					102: {"P3", true}, 106: {"P3", true}}),
+			poolWanted: makeBlockPool(testBcR, 100,
+				[]BpPeer{{ID: "P2", Height: 120}, {ID: "P3", Height: 130}},
+				map[int64]tPBlocks{
+					101: {"P2", true}, 103: {"P2", false},
+					102: {"P3", true}, 106: {"P3", true}}),
+		},
+		{
+			name: "multiple peers, remove peer for block at H+1",
+			pool: makeBlockPool(testBcR, 100,
+				[]BpPeer{{ID: "P1", Height: 120}, {ID: "P2", Height: 120}, {ID: "P3", Height: 130}},
+				map[int64]tPBlocks{
+					100: {"P1", true}, 104: {"P1", true}, 105: {"P1", false},
+					101: {"P2", false}, 103: {"P2", false},
+					102: {"P3", true}, 106: {"P3", true}}),
+			poolWanted: makeBlockPool(testBcR, 100,
+				[]BpPeer{{ID: "P1", Height: 120}, {ID: "P3", Height: 130}},
+				map[int64]tPBlocks{
+					100: {"P1", true}, 104: {"P1", true}, 105: {"P1", false},
+					102: {"P3", true}, 106: {"P3", true}}),
+		},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			tt.pool.RemovePeerAtCurrentHeights(errNoPeerResponse)
+			assertBlockPoolEquivalent(t, tt.poolWanted, tt.pool)
+		})
+	}
+}

blockchain/v1/reactor.go

@@ -0,0 +1,570 @@
+package v1
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/gogo/protobuf/proto"
+
+	"github.com/tendermint/tendermint/behaviour"
+	bc "github.com/tendermint/tendermint/blockchain"
+	"github.com/tendermint/tendermint/libs/log"
+	"github.com/tendermint/tendermint/p2p"
+	bcproto "github.com/tendermint/tendermint/proto/tendermint/blockchain"
+	sm "github.com/tendermint/tendermint/state"
+	"github.com/tendermint/tendermint/store"
+	"github.com/tendermint/tendermint/types"
+)
+
+const (
+	// BlockchainChannel is a channel for blocks and status updates (`BlockStore` height)
+	BlockchainChannel = byte(0x40)
+	trySyncIntervalMS = 10
+	trySendIntervalMS = 10
+
+	// ask for best height every 10s
+	statusUpdateIntervalSeconds = 10
+)
+
+var (
+	// Maximum number of requests that can be pending per peer, i.e. for which requests have been sent but blocks
+	// have not been received.
+	maxRequestsPerPeer = 20
+	// Maximum number of block requests for the reactor, pending or for which blocks have been received.
+	maxNumRequests = 64
+)
+
+type consensusReactor interface {
+	// for when we switch from blockchain reactor and fast sync to
+	// the consensus machine
+	SwitchToConsensus(state sm.State, skipWAL bool)
+}
+
+// BlockchainReactor handles long-term catchup syncing.
+type BlockchainReactor struct {
+	p2p.BaseReactor
+
+	initialState sm.State // immutable
+	state        sm.State
+
+	blockExec *sm.BlockExecutor
+	store     *store.BlockStore
+
+	fastSync    bool
+	stateSynced bool
+
+	fsm          *BcReactorFSM
+	blocksSynced uint64
+
+	// Receive goroutine forwards messages to this channel to be processed in the context of the poolRoutine.
+	messagesForFSMCh chan bcReactorMessage
+
+	// Switch goroutine may send RemovePeer to the blockchain reactor. This is an error message that is relayed
+	// to this channel to be processed in the context of the poolRoutine.
+	errorsForFSMCh chan bcReactorMessage
+
+	// This channel is used by the FSM and indirectly the block pool to report errors to the blockchain reactor and
+	// the switch.
+	eventsFromFSMCh chan bcFsmMessage
+
+	swReporter *behaviour.SwitchReporter
+}
+
+// NewBlockchainReactor returns new reactor instance.
+func NewBlockchainReactor(state sm.State, blockExec *sm.BlockExecutor, store *store.BlockStore,
+	fastSync bool) *BlockchainReactor {
+
+	if state.LastBlockHeight != store.Height() {
+		panic(fmt.Sprintf("state (%v) and store (%v) height mismatch", state.LastBlockHeight,
+			store.Height()))
+	}
+
+	const capacity = 1000
+	eventsFromFSMCh := make(chan bcFsmMessage, capacity)
+	messagesForFSMCh := make(chan bcReactorMessage, capacity)
+	errorsForFSMCh := make(chan bcReactorMessage, capacity)
+
+	startHeight := store.Height() + 1
+	if startHeight == 1 {
+		startHeight = state.InitialHeight
+	}
+	bcR := &BlockchainReactor{
+		initialState:     state,
+		state:            state,
+		blockExec:        blockExec,
+		fastSync:         fastSync,
+		store:            store,
+		messagesForFSMCh: messagesForFSMCh,
+		eventsFromFSMCh:  eventsFromFSMCh,
+		errorsForFSMCh:   errorsForFSMCh,
+	}
+	fsm := NewFSM(startHeight, bcR)
+	bcR.fsm = fsm
+	bcR.BaseReactor = *p2p.NewBaseReactor("BlockchainReactor", bcR)
+	// bcR.swReporter = behaviour.NewSwitchReporter(bcR.BaseReactor.Switch)
+
+	return bcR
+}
+
+// bcReactorMessage is used by the reactor to send messages to the FSM.
+type bcReactorMessage struct {
+	event bReactorEvent
+	data  bReactorEventData
+}
+
+type bFsmEvent uint
+
+const (
+	// message type events
+	peerErrorEv = iota + 1
+	syncFinishedEv
+)
+
+type bFsmEventData struct {
+	peerID p2p.ID
+	err    error
+}
+
+// bcFsmMessage is used by the FSM to send messages to the reactor
+type bcFsmMessage struct {
+	event bFsmEvent
+	data  bFsmEventData
+}
+
+// SetLogger implements service.Service by setting the logger on reactor and pool.
+func (bcR *BlockchainReactor) SetLogger(l log.Logger) {
+	bcR.BaseService.Logger = l
+	bcR.fsm.SetLogger(l)
+}
+
+// OnStart implements service.Service.
+func (bcR *BlockchainReactor) OnStart() error {
+	bcR.swReporter = behaviour.NewSwitchReporter(bcR.BaseReactor.Switch)
+	if bcR.fastSync {
+		go bcR.poolRoutine()
+	}
+	return nil
+}
+
+// OnStop implements service.Service.
+func (bcR *BlockchainReactor) OnStop() {
+	_ = bcR.Stop()
+}
+
+// SwitchToFastSync is called by the state sync reactor when switching to fast sync.
+func (bcR *BlockchainReactor) SwitchToFastSync(state sm.State) error {
+	bcR.fastSync = true
+	bcR.initialState = state
+	bcR.state = state
+	bcR.stateSynced = true
+
+	bcR.fsm = NewFSM(state.LastBlockHeight+1, bcR)
+	bcR.fsm.SetLogger(bcR.Logger)
+	go bcR.poolRoutine()
+	return nil
+}
+
+// GetChannels implements Reactor
+func (bcR *BlockchainReactor) GetChannels() []*p2p.ChannelDescriptor {
+	return []*p2p.ChannelDescriptor{
+		{
+			ID:                  BlockchainChannel,
+			Priority:            10,
+			SendQueueCapacity:   2000,
+			RecvBufferCapacity:  50 * 4096,
+			RecvMessageCapacity: bc.MaxMsgSize,
+			MessageType:         &bcproto.Message{},
+		},
+	}
+}
+
+// AddPeer implements Reactor by sending our state to peer.
+func (bcR *BlockchainReactor) AddPeer(peer p2p.Peer) {
+	p2p.SendEnvelopeShim(peer, p2p.Envelope{ //nolint: staticcheck
+		ChannelID: BlockchainChannel,
+		Message: &bcproto.StatusResponse{
+			Base:   bcR.store.Base(),
+			Height: bcR.store.Height(),
+		},
+	}, bcR.Logger)
+	// it's OK if send fails. will try later in poolRoutine
+
+	// peer is added to the pool once we receive the first
+	// bcStatusResponseMessage from the peer and call pool.updatePeer()
+}
+
+// sendBlockToPeer loads a block and sends it to the requesting peer.
+// If the block doesn't exist a bcNoBlockResponseMessage is sent.
+// If all nodes are honest, no node should be requesting for a block that doesn't exist.
+func (bcR *BlockchainReactor) sendBlockToPeer(msg *bcproto.BlockRequest,
+	src p2p.Peer) (queued bool) {
+
+	block := bcR.store.LoadBlock(msg.Height)
+	if block != nil {
+		pbbi, err := block.ToProto()
+		if err != nil {
+			bcR.Logger.Error("Could not send block message to peer", "err", err)
+			return false
+		}
+		return p2p.TrySendEnvelopeShim(src, p2p.Envelope{ //nolint: staticcheck
+			ChannelID: BlockchainChannel,
+			Message:   &bcproto.BlockResponse{Block: pbbi},
+		}, bcR.Logger)
+	}
+
+	bcR.Logger.Info("peer asking for a block we don't have", "src", src, "height", msg.Height)
+
+	return p2p.TrySendEnvelopeShim(src, p2p.Envelope{ //nolint: staticcheck
+		ChannelID: BlockchainChannel,
+		Message:   &bcproto.NoBlockResponse{Height: msg.Height},
+	}, bcR.Logger)
+}
+
+func (bcR *BlockchainReactor) sendStatusResponseToPeer(msg *bcproto.StatusRequest, src p2p.Peer) (queued bool) {
+	return p2p.TrySendEnvelopeShim(src, p2p.Envelope{ //nolint: staticcheck
+		ChannelID: BlockchainChannel,
+		Message: &bcproto.StatusResponse{
+			Base:   bcR.store.Base(),
+			Height: bcR.store.Height(),
+		},
+	}, bcR.Logger)
+}
+
+// RemovePeer implements Reactor by removing peer from the pool.
+func (bcR *BlockchainReactor) RemovePeer(peer p2p.Peer, reason interface{}) {
+	msgData := bcReactorMessage{
+		event: peerRemoveEv,
+		data: bReactorEventData{
+			peerID: peer.ID(),
+			err:    errSwitchRemovesPeer,
+		},
+	}
+	bcR.errorsForFSMCh <- msgData
+}
+
+// Receive implements Reactor by handling 4 types of messages (look below).
+func (bcR *BlockchainReactor) ReceiveEnvelope(e p2p.Envelope) {
+	if err := bc.ValidateMsg(e.Message); err != nil {
+		bcR.Logger.Error("peer sent us invalid msg", "peer", e.Src, "msg", e.Message, "err", err)
+		_ = bcR.swReporter.Report(behaviour.BadMessage(e.Src.ID(), err.Error()))
+		return
+	}
+
+	bcR.Logger.Debug("Receive", "src", e.Src, "chID", e.ChannelID, "msg", e.Message)
+
+	switch msg := e.Message.(type) {
+	case *bcproto.BlockRequest:
+		if queued := bcR.sendBlockToPeer(msg, e.Src); !queued {
+			// Unfortunately not queued since the queue is full.
+			bcR.Logger.Error("Could not send block message to peer", "src", e.Src, "height", msg.Height)
+		}
+
+	case *bcproto.StatusRequest:
+		// Send peer our state.
+		if queued := bcR.sendStatusResponseToPeer(msg, e.Src); !queued {
+			// Unfortunately not queued since the queue is full.
+			bcR.Logger.Error("Could not send status message to peer", "src", e.Src)
+		}
+
+	case *bcproto.BlockResponse:
+		bi, err := types.BlockFromProto(msg.Block)
+		if err != nil {
+			bcR.Logger.Error("error transition block from protobuf", "err", err)
+			return
+		}
+		msgForFSM := bcReactorMessage{
+			event: blockResponseEv,
+			data: bReactorEventData{
+				peerID: e.Src.ID(),
+				height: bi.Height,
+				block:  bi,
+				length: msg.Size(),
+			},
+		}
+		bcR.Logger.Info("Received", "src", e.Src, "height", bi.Height)
+		bcR.messagesForFSMCh <- msgForFSM
+	case *bcproto.NoBlockResponse:
+		msgForFSM := bcReactorMessage{
+			event: noBlockResponseEv,
+			data: bReactorEventData{
+				peerID: e.Src.ID(),
+				height: msg.Height,
+			},
+		}
+		bcR.Logger.Debug("Peer does not have requested block", "peer", e.Src, "height", msg.Height)
+		bcR.messagesForFSMCh <- msgForFSM
+
+	case *bcproto.StatusResponse:
+		// Got a peer status. Unverified.
+		msgForFSM := bcReactorMessage{
+			event: statusResponseEv,
+			data: bReactorEventData{
+				peerID: e.Src.ID(),
+				height: msg.Height,
+				length: msg.Size(),
+			},
+		}
+		bcR.messagesForFSMCh <- msgForFSM
+
+	default:
+		bcR.Logger.Error(fmt.Sprintf("unknown message type %T", msg))
+	}
+}
+
+func (bcR *BlockchainReactor) Receive(chID byte, peer p2p.Peer, msgBytes []byte) {
+	msg := &bcproto.Message{}
+	err := proto.Unmarshal(msgBytes, msg)
+	if err != nil {
+		panic(err)
+	}
+	uw, err := msg.Unwrap()
+	if err != nil {
+		panic(err)
+	}
+	bcR.ReceiveEnvelope(p2p.Envelope{
+		ChannelID: chID,
+		Src:       peer,
+		Message:   uw,
+	})
+}
+
+// processBlocksRoutine processes blocks until signlaed to stop over the stopProcessing channel
+func (bcR *BlockchainReactor) processBlocksRoutine(stopProcessing chan struct{}) {
+
+	processReceivedBlockTicker := time.NewTicker(trySyncIntervalMS * time.Millisecond)
+	doProcessBlockCh := make(chan struct{}, 1)
+
+	lastHundred := time.Now()
+	lastRate := 0.0
+
+ForLoop:
+	for {
+		select {
+		case <-stopProcessing:
+			bcR.Logger.Info("finishing block execution")
+			break ForLoop
+		case <-processReceivedBlockTicker.C: // try to execute blocks
+			select {
+			case doProcessBlockCh <- struct{}{}:
+			default:
+			}
+		case <-doProcessBlockCh:
+			for {
+				err := bcR.processBlock()
+				if err == errMissingBlock {
+					break
+				}
+				// Notify FSM of block processing result.
+				msgForFSM := bcReactorMessage{
+					event: processedBlockEv,
+					data: bReactorEventData{
+						err: err,
+					},
+				}
+				_ = bcR.fsm.Handle(&msgForFSM)
+
+				if err != nil {
+					break
+				}
+
+				bcR.blocksSynced++
+				if bcR.blocksSynced%100 == 0 {
+					lastRate = 0.9*lastRate + 0.1*(100/time.Since(lastHundred).Seconds())
+					height, maxPeerHeight := bcR.fsm.Status()
+					bcR.Logger.Info("Fast Sync Rate", "height", height,
+						"max_peer_height", maxPeerHeight, "blocks/s", lastRate)
+					lastHundred = time.Now()
+				}
+			}
+		}
+	}
+}
+
+// poolRoutine receives and handles messages from the Receive() routine and from the FSM.
+func (bcR *BlockchainReactor) poolRoutine() {
+
+	bcR.fsm.Start()
+
+	sendBlockRequestTicker := time.NewTicker(trySendIntervalMS * time.Millisecond)
+	statusUpdateTicker := time.NewTicker(statusUpdateIntervalSeconds * time.Second)
+
+	stopProcessing := make(chan struct{}, 1)
+	go bcR.processBlocksRoutine(stopProcessing)
+
+ForLoop:
+	for {
+		select {
+
+		case <-sendBlockRequestTicker.C:
+			if !bcR.fsm.NeedsBlocks() {
+				continue
+			}
+			_ = bcR.fsm.Handle(&bcReactorMessage{
+				event: makeRequestsEv,
+				data: bReactorEventData{
+					maxNumRequests: maxNumRequests}})
+
+		case <-statusUpdateTicker.C:
+			// Ask for status updates.
+			go bcR.sendStatusRequest()
+
+		case msg := <-bcR.messagesForFSMCh:
+			// Sent from the Receive() routine when status (statusResponseEv) and
+			// block (blockResponseEv) response events are received
+			_ = bcR.fsm.Handle(&msg)
+
+		case msg := <-bcR.errorsForFSMCh:
+			// Sent from the switch.RemovePeer() routine (RemovePeerEv) and
+			// FSM state timer expiry routine (stateTimeoutEv).
+			_ = bcR.fsm.Handle(&msg)
+
+		case msg := <-bcR.eventsFromFSMCh:
+			switch msg.event {
+			case syncFinishedEv:
+				stopProcessing <- struct{}{}
+				// Sent from the FSM when it enters finished state.
+				break ForLoop
+			case peerErrorEv:
+				// Sent from the FSM when it detects peer error
+				bcR.reportPeerErrorToSwitch(msg.data.err, msg.data.peerID)
+				if msg.data.err == errNoPeerResponse {
+					// Sent from the peer timeout handler routine
+					_ = bcR.fsm.Handle(&bcReactorMessage{
+						event: peerRemoveEv,
+						data: bReactorEventData{
+							peerID: msg.data.peerID,
+							err:    msg.data.err,
+						},
+					})
+				}
+				// else {
+				// For slow peers, or errors due to blocks received from wrong peer
+				// the FSM had already removed the peers
+				// }
+			default:
+				bcR.Logger.Error("Event from FSM not supported", "type", msg.event)
+			}
+
+		case <-bcR.Quit():
+			break ForLoop
+		}
+	}
+}
+
+func (bcR *BlockchainReactor) reportPeerErrorToSwitch(err error, peerID p2p.ID) {
+	peer := bcR.Switch.Peers().Get(peerID)
+	if peer != nil {
+		_ = bcR.swReporter.Report(behaviour.BadMessage(peerID, err.Error()))
+	}
+}
+
+func (bcR *BlockchainReactor) processBlock() error {
+
+	first, second, err := bcR.fsm.FirstTwoBlocks()
+	if err != nil {
+		// We need both to sync the first block.
+		return err
+	}
+
+	chainID := bcR.initialState.ChainID
+
+	firstParts := first.MakePartSet(types.BlockPartSizeBytes)
+	firstPartSetHeader := firstParts.Header()
+	firstID := types.BlockID{Hash: first.Hash(), PartSetHeader: firstPartSetHeader}
+	// Finally, verify the first block using the second's commit
+	// NOTE: we can probably make this more efficient, but note that calling
+	// first.Hash() doesn't verify the tx contents, so MakePartSet() is
+	// currently necessary.
+	err = bcR.state.Validators.VerifyCommitLight(chainID, firstID, first.Height, second.LastCommit)
+	if err != nil {
+		bcR.Logger.Error("error during commit verification", "err", err,
+			"first", first.Height, "second", second.Height)
+		return errBlockVerificationFailure
+	}
+
+	bcR.store.SaveBlock(first, firstParts, second.LastCommit)
+
+	bcR.state, _, err = bcR.blockExec.ApplyBlock(bcR.state, firstID, first)
+	if err != nil {
+		panic(fmt.Sprintf("failed to process committed block (%d:%X): %v", first.Height, first.Hash(), err))
+	}
+
+	return nil
+}
+
+// Implements bcRNotifier
+// sendStatusRequest broadcasts `BlockStore` height.
+func (bcR *BlockchainReactor) sendStatusRequest() {
+	bcR.Switch.BroadcastEnvelope(p2p.Envelope{
+		ChannelID: BlockchainChannel,
+		Message:   &bcproto.StatusRequest{},
+	})
+}
+
+// Implements bcRNotifier
+// BlockRequest sends `BlockRequest` height.
+func (bcR *BlockchainReactor) sendBlockRequest(peerID p2p.ID, height int64) error {
+	peer := bcR.Switch.Peers().Get(peerID)
+	if peer == nil {
+		return errNilPeerForBlockRequest
+	}
+
+	queued := p2p.TrySendEnvelopeShim(peer, p2p.Envelope{ //nolint: staticcheck
+		ChannelID: BlockchainChannel,
+		Message:   &bcproto.BlockRequest{Height: height},
+	}, bcR.Logger)
+	if !queued {
+		return errSendQueueFull
+	}
+	return nil
+}
+
+// Implements bcRNotifier
+func (bcR *BlockchainReactor) switchToConsensus() {
+	conR, ok := bcR.Switch.Reactor("CONSENSUS").(consensusReactor)
+	if ok {
+		conR.SwitchToConsensus(bcR.state, bcR.blocksSynced > 0 || bcR.stateSynced)
+		bcR.eventsFromFSMCh <- bcFsmMessage{event: syncFinishedEv}
+	}
+	// else {
+	// Should only happen during testing.
+	// }
+}
+
+// Implements bcRNotifier
+// Called by FSM and pool:
+// - pool calls when it detects slow peer or when peer times out
+// - FSM calls when:
+//   - adding a block (addBlock) fails
+//   - reactor processing of a block reports failure and FSM sends back the peers of first and second blocks
+func (bcR *BlockchainReactor) sendPeerError(err error, peerID p2p.ID) {
+	bcR.Logger.Info("sendPeerError:", "peer", peerID, "error", err)
+	msgData := bcFsmMessage{
+		event: peerErrorEv,
+		data: bFsmEventData{
+			peerID: peerID,
+			err:    err,
+		},
+	}
+	bcR.eventsFromFSMCh <- msgData
+}
+
+// Implements bcRNotifier
+func (bcR *BlockchainReactor) resetStateTimer(name string, timer **time.Timer, timeout time.Duration) {
+	if timer == nil {
+		panic("nil timer pointer parameter")
+	}
+	if *timer == nil {
+		*timer = time.AfterFunc(timeout, func() {
+			msg := bcReactorMessage{
+				event: stateTimeoutEv,
+				data: bReactorEventData{
+					stateName: name,
+				},
+			}
+			bcR.errorsForFSMCh <- msg
+		})
+	} else {
+		(*timer).Reset(timeout)
+	}
+}

blockchain/v1/reactor_fsm.go

@@ -0,0 +1,462 @@
+package v1
+
+import (
+	"errors"
+	"fmt"
+	"sync"
+	"time"
+
+	"github.com/tendermint/tendermint/libs/log"
+	"github.com/tendermint/tendermint/p2p"
+	"github.com/tendermint/tendermint/types"
+)
+
+// Blockchain Reactor State
+type bcReactorFSMState struct {
+	name string
+
+	// called when transitioning out of current state
+	handle func(*BcReactorFSM, bReactorEvent, bReactorEventData) (next *bcReactorFSMState, err error)
+	// called when entering the state
+	enter func(fsm *BcReactorFSM)
+
+	// timeout to ensure FSM is not stuck in a state forever
+	// the timer is owned and run by the fsm instance
+	timeout time.Duration
+}
+
+func (s *bcReactorFSMState) String() string {
+	return s.name
+}
+
+// BcReactorFSM is the datastructure for the Blockchain Reactor State Machine
+type BcReactorFSM struct {
+	logger log.Logger
+	mtx    sync.Mutex
+
+	startTime time.Time
+
+	state      *bcReactorFSMState
+	stateTimer *time.Timer
+	pool       *BlockPool
+
+	// interface used to call the Blockchain reactor to send StatusRequest, BlockRequest, reporting errors, etc.
+	toBcR bcReactor
+}
+
+// NewFSM creates a new reactor FSM.
+func NewFSM(height int64, toBcR bcReactor) *BcReactorFSM {
+	return &BcReactorFSM{
+		state:     unknown,
+		startTime: time.Now(),
+		pool:      NewBlockPool(height, toBcR),
+		toBcR:     toBcR,
+	}
+}
+
+// bReactorEventData is part of the message sent by the reactor to the FSM and used by the state handlers.
+type bReactorEventData struct {
+	peerID         p2p.ID
+	err            error        // for peer error: timeout, slow; for processed block event if error occurred
+	base           int64        // for status response
+	height         int64        // for status response; for processed block event
+	block          *types.Block // for block response
+	stateName      string       // for state timeout events
+	length         int          // for block response event, length of received block, used to detect slow peers
+	maxNumRequests int          // for request needed event, maximum number of pending requests
+}
+
+// Blockchain Reactor Events (the input to the state machine)
+type bReactorEvent uint
+
+const (
+	// message type events
+	startFSMEv = iota + 1
+	statusResponseEv
+	blockResponseEv
+	noBlockResponseEv
+	processedBlockEv
+	makeRequestsEv
+	stopFSMEv
+
+	// other events
+	peerRemoveEv = iota + 256
+	stateTimeoutEv
+)
+
+func (msg *bcReactorMessage) String() string {
+	var dataStr string
+
+	switch msg.event {
+	case startFSMEv:
+		dataStr = ""
+	case statusResponseEv:
+		dataStr = fmt.Sprintf("peer=%v base=%v height=%v", msg.data.peerID, msg.data.base, msg.data.height)
+	case blockResponseEv:
+		dataStr = fmt.Sprintf("peer=%v block.height=%v length=%v",
+			msg.data.peerID, msg.data.block.Height, msg.data.length)
+	case noBlockResponseEv:
+		dataStr = fmt.Sprintf("peer=%v requested height=%v",
+			msg.data.peerID, msg.data.height)
+	case processedBlockEv:
+		dataStr = fmt.Sprintf("error=%v", msg.data.err)
+	case makeRequestsEv:
+		dataStr = ""
+	case stopFSMEv:
+		dataStr = ""
+	case peerRemoveEv:
+		dataStr = fmt.Sprintf("peer: %v is being removed by the switch", msg.data.peerID)
+	case stateTimeoutEv:
+		dataStr = fmt.Sprintf("state=%v", msg.data.stateName)
+	default:
+		dataStr = "cannot interpret message data"
+	}
+
+	return fmt.Sprintf("%v: %v", msg.event, dataStr)
+}
+
+func (ev bReactorEvent) String() string {
+	switch ev {
+	case startFSMEv:
+		return "startFSMEv"
+	case statusResponseEv:
+		return "statusResponseEv"
+	case blockResponseEv:
+		return "blockResponseEv"
+	case noBlockResponseEv:
+		return "noBlockResponseEv"
+	case processedBlockEv:
+		return "processedBlockEv"
+	case makeRequestsEv:
+		return "makeRequestsEv"
+	case stopFSMEv:
+		return "stopFSMEv"
+	case peerRemoveEv:
+		return "peerRemoveEv"
+	case stateTimeoutEv:
+		return "stateTimeoutEv"
+	default:
+		return "event unknown"
+	}
+
+}
+
+// states
+var (
+	unknown      *bcReactorFSMState
+	waitForPeer  *bcReactorFSMState
+	waitForBlock *bcReactorFSMState
+	finished     *bcReactorFSMState
+)
+
+// timeouts for state timers
+const (
+	waitForPeerTimeout                 = 3 * time.Second
+	waitForBlockAtCurrentHeightTimeout = 10 * time.Second
+)
+
+// errors
+var (
+	// internal to the package
+	errNoErrorFinished        = errors.New("fast sync is finished")
+	errInvalidEvent           = errors.New("invalid event in current state")
+	errMissingBlock           = errors.New("missing blocks")
+	errNilPeerForBlockRequest = errors.New("peer for block request does not exist in the switch")
+	errSendQueueFull          = errors.New("block request not made, send-queue is full")
+	errPeerTooShort           = errors.New("peer height too low, old peer removed/ new peer not added")
+	errSwitchRemovesPeer      = errors.New("switch is removing peer")
+	errTimeoutEventWrongState = errors.New("timeout event for a state different than the current one")
+	errNoTallerPeer           = errors.New("fast sync timed out on waiting for a peer taller than this node")
+
+	// reported eventually to the switch
+	// handle return
+	errPeerLowersItsHeight = errors.New("fast sync peer reports a height lower than previous")
+	// handle return
+	errNoPeerResponseForCurrentHeights = errors.New("fast sync timed out on peer block response for current heights")
+	errNoPeerResponse                  = errors.New("fast sync timed out on peer block response")               // xx
+	errBadDataFromPeer                 = errors.New("fast sync received block from wrong peer or block is bad") // xx
+	errDuplicateBlock                  = errors.New("fast sync received duplicate block from peer")
+	errBlockVerificationFailure        = errors.New("fast sync block verification failure")              // xx
+	errSlowPeer                        = errors.New("fast sync peer is not sending us data fast enough") // xx
+
+)
+
+func init() {
+	unknown = &bcReactorFSMState{
+		name: "unknown",
+		handle: func(fsm *BcReactorFSM, ev bReactorEvent, data bReactorEventData) (*bcReactorFSMState, error) {
+			switch ev {
+			case startFSMEv:
+				// Broadcast Status message. Currently doesn't return non-nil error.
+				fsm.toBcR.sendStatusRequest()
+				return waitForPeer, nil
+
+			case stopFSMEv:
+				return finished, errNoErrorFinished
+
+			default:
+				return unknown, errInvalidEvent
+			}
+		},
+	}
+
+	waitForPeer = &bcReactorFSMState{
+		name:    "waitForPeer",
+		timeout: waitForPeerTimeout,
+		enter: func(fsm *BcReactorFSM) {
+			// Stop when leaving the state.
+			fsm.resetStateTimer()
+		},
+		handle: func(fsm *BcReactorFSM, ev bReactorEvent, data bReactorEventData) (*bcReactorFSMState, error) {
+			switch ev {
+			case stateTimeoutEv:
+				if data.stateName != "waitForPeer" {
+					fsm.logger.Error("received a state timeout event for different state",
+						"state", data.stateName)
+					return waitForPeer, errTimeoutEventWrongState
+				}
+				// There was no statusResponse received from any peer.
+				// Should we send status request again?
+				return finished, errNoTallerPeer
+
+			case statusResponseEv:
+				if err := fsm.pool.UpdatePeer(data.peerID, data.base, data.height); err != nil {
+					if fsm.pool.NumPeers() == 0 {
+						return waitForPeer, err
+					}
+				}
+				if fsm.stateTimer != nil {
+					fsm.stateTimer.Stop()
+				}
+				return waitForBlock, nil
+
+			case stopFSMEv:
+				if fsm.stateTimer != nil {
+					fsm.stateTimer.Stop()
+				}
+				return finished, errNoErrorFinished
+
+			default:
+				return waitForPeer, errInvalidEvent
+			}
+		},
+	}
+
+	waitForBlock = &bcReactorFSMState{
+		name:    "waitForBlock",
+		timeout: waitForBlockAtCurrentHeightTimeout,
+		enter: func(fsm *BcReactorFSM) {
+			// Stop when leaving the state.
+			fsm.resetStateTimer()
+		},
+		handle: func(fsm *BcReactorFSM, ev bReactorEvent, data bReactorEventData) (*bcReactorFSMState, error) {
+			switch ev {
+
+			case statusResponseEv:
+				err := fsm.pool.UpdatePeer(data.peerID, data.base, data.height)
+				if fsm.pool.NumPeers() == 0 {
+					return waitForPeer, err
+				}
+				if fsm.pool.ReachedMaxHeight() {
+					return finished, err
+				}
+				return waitForBlock, err
+
+			case blockResponseEv:
+				fsm.logger.Debug("blockResponseEv", "H", data.block.Height)
+				err := fsm.pool.AddBlock(data.peerID, data.block, data.length)
+				if err != nil {
+					// A block was received that was unsolicited, from unexpected peer, or that we already have it.
+					// Ignore block, remove peer and send error to switch.
+					fsm.pool.RemovePeer(data.peerID, err)
+					fsm.toBcR.sendPeerError(err, data.peerID)
+				}
+				if fsm.pool.NumPeers() == 0 {
+					return waitForPeer, err
+				}
+				return waitForBlock, err
+			case noBlockResponseEv:
+				fsm.logger.Error("peer does not have requested block", "peer", data.peerID)
+
+				return waitForBlock, nil
+			case processedBlockEv:
+				if data.err != nil {
+					first, second, _ := fsm.pool.FirstTwoBlocksAndPeers()
+					fsm.logger.Error("error processing block", "err", data.err,
+						"first", first.block.Height, "second", second.block.Height)
+					fsm.logger.Error("send peer error for", "peer", first.peer.ID)
+					fsm.toBcR.sendPeerError(data.err, first.peer.ID)
+					fsm.logger.Error("send peer error for", "peer", second.peer.ID)
+					fsm.toBcR.sendPeerError(data.err, second.peer.ID)
+					// Remove the first two blocks. This will also remove the peers
+					fsm.pool.InvalidateFirstTwoBlocks(data.err)
+				} else {
+					fsm.pool.ProcessedCurrentHeightBlock()
+					// Since we advanced one block reset the state timer
+					fsm.resetStateTimer()
+				}
+
+				// Both cases above may result in achieving maximum height.
+				if fsm.pool.ReachedMaxHeight() {
+					return finished, nil
+				}
+
+				return waitForBlock, data.err
+
+			case peerRemoveEv:
+				// This event is sent by the switch to remove disconnected and errored peers.
+				fsm.pool.RemovePeer(data.peerID, data.err)
+				if fsm.pool.NumPeers() == 0 {
+					return waitForPeer, nil
+				}
+				if fsm.pool.ReachedMaxHeight() {
+					return finished, nil
+				}
+				return waitForBlock, nil
+
+			case makeRequestsEv:
+				fsm.makeNextRequests(data.maxNumRequests)
+				return waitForBlock, nil
+
+			case stateTimeoutEv:
+				if data.stateName != "waitForBlock" {
+					fsm.logger.Error("received a state timeout event for different state",
+						"state", data.stateName)
+					return waitForBlock, errTimeoutEventWrongState
+				}
+				// We haven't received the block at current height or height+1. Remove peer.
+				fsm.pool.RemovePeerAtCurrentHeights(errNoPeerResponseForCurrentHeights)
+				fsm.resetStateTimer()
+				if fsm.pool.NumPeers() == 0 {
+					return waitForPeer, errNoPeerResponseForCurrentHeights
+				}
+				if fsm.pool.ReachedMaxHeight() {
+					return finished, nil
+				}
+				return waitForBlock, errNoPeerResponseForCurrentHeights
+
+			case stopFSMEv:
+				if fsm.stateTimer != nil {
+					fsm.stateTimer.Stop()
+				}
+				return finished, errNoErrorFinished
+
+			default:
+				return waitForBlock, errInvalidEvent
+			}
+		},
+	}
+
+	finished = &bcReactorFSMState{
+		name: "finished",
+		enter: func(fsm *BcReactorFSM) {
+			fsm.logger.Info("Time to switch to consensus reactor!", "height", fsm.pool.Height)
+			fsm.toBcR.switchToConsensus()
+			fsm.cleanup()
+		},
+		handle: func(fsm *BcReactorFSM, ev bReactorEvent, data bReactorEventData) (*bcReactorFSMState, error) {
+			return finished, nil
+		},
+	}
+}
+
+// Interface used by FSM for sending Block and Status requests,
+// informing of peer errors and state timeouts
+// Implemented by BlockchainReactor and tests
+type bcReactor interface {
+	sendStatusRequest()
+	sendBlockRequest(peerID p2p.ID, height int64) error
+	sendPeerError(err error, peerID p2p.ID)
+	resetStateTimer(name string, timer **time.Timer, timeout time.Duration)
+	switchToConsensus()
+}
+
+// SetLogger sets the FSM logger.
+func (fsm *BcReactorFSM) SetLogger(l log.Logger) {
+	fsm.logger = l
+	fsm.pool.SetLogger(l)
+}
+
+// Start starts the FSM.
+func (fsm *BcReactorFSM) Start() {
+	_ = fsm.Handle(&bcReactorMessage{event: startFSMEv})
+}
+
+// Handle processes messages and events sent to the FSM.
+func (fsm *BcReactorFSM) Handle(msg *bcReactorMessage) error {
+	fsm.mtx.Lock()
+	defer fsm.mtx.Unlock()
+	fsm.logger.Debug("FSM received", "event", msg, "state", fsm.state)
+
+	if fsm.state == nil {
+		fsm.state = unknown
+	}
+	next, err := fsm.state.handle(fsm, msg.event, msg.data)
+	if err != nil {
+		fsm.logger.Error("FSM event handler returned", "err", err,
+			"state", fsm.state, "event", msg.event)
+	}
+
+	oldState := fsm.state.name
+	fsm.transition(next)
+	if oldState != fsm.state.name {
+		fsm.logger.Info("FSM changed state", "new_state", fsm.state)
+	}
+	return err
+}
+
+func (fsm *BcReactorFSM) transition(next *bcReactorFSMState) {
+	if next == nil {
+		return
+	}
+	if fsm.state != next {
+		fsm.state = next
+		if next.enter != nil {
+			next.enter(fsm)
+		}
+	}
+}
+
+// Called when entering an FSM state in order to detect lack of progress in the state machine.
+// Note the use of the 'bcr' interface to facilitate testing without timer expiring.
+func (fsm *BcReactorFSM) resetStateTimer() {
+	fsm.toBcR.resetStateTimer(fsm.state.name, &fsm.stateTimer, fsm.state.timeout)
+}
+
+func (fsm *BcReactorFSM) isCaughtUp() bool {
+	return fsm.state == finished
+}
+
+func (fsm *BcReactorFSM) makeNextRequests(maxNumRequests int) {
+	fsm.pool.MakeNextRequests(maxNumRequests)
+}
+
+func (fsm *BcReactorFSM) cleanup() {
+	fsm.pool.Cleanup()
+}
+
+// NeedsBlocks checks if more block requests are required.
+func (fsm *BcReactorFSM) NeedsBlocks() bool {
+	fsm.mtx.Lock()
+	defer fsm.mtx.Unlock()
+	return fsm.state.name == "waitForBlock" && fsm.pool.NeedsBlocks()
+}
+
+// FirstTwoBlocks returns the two blocks at pool height and height+1
+func (fsm *BcReactorFSM) FirstTwoBlocks() (first, second *types.Block, err error) {
+	fsm.mtx.Lock()
+	defer fsm.mtx.Unlock()
+	firstBP, secondBP, err := fsm.pool.FirstTwoBlocksAndPeers()
+	if err == nil {
+		first = firstBP.block
+		second = secondBP.block
+	}
+	return
+}
+
+// Status returns the pool's height and the maximum peer height.
+func (fsm *BcReactorFSM) Status() (height, maxPeerHeight int64) {
+	fsm.mtx.Lock()
+	defer fsm.mtx.Unlock()
+	return fsm.pool.Height, fsm.pool.MaxPeerHeight
+}

blockchain/v1/reactor_fsm_test.go

@@ -0,0 +1,944 @@
+package v1
+
+import (
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+
+	"github.com/tendermint/tendermint/libs/log"
+	tmmath "github.com/tendermint/tendermint/libs/math"
+	tmrand "github.com/tendermint/tendermint/libs/rand"
+	"github.com/tendermint/tendermint/p2p"
+	"github.com/tendermint/tendermint/types"
+)
+
+type lastBlockRequestT struct {
+	peerID p2p.ID
+	height int64
+}
+
+type lastPeerErrorT struct {
+	peerID p2p.ID
+	err    error
+}
+
+// reactor for FSM testing
+type testReactor struct {
+	logger            log.Logger
+	fsm               *BcReactorFSM
+	numStatusRequests int
+	numBlockRequests  int
+	lastBlockRequest  lastBlockRequestT
+	lastPeerError     lastPeerErrorT
+	stateTimerStarts  map[string]int
+}
+
+func sendEventToFSM(fsm *BcReactorFSM, ev bReactorEvent, data bReactorEventData) error {
+	return fsm.Handle(&bcReactorMessage{event: ev, data: data})
+}
+
+type fsmStepTestValues struct {
+	currentState string
+	event        bReactorEvent
+	data         bReactorEventData
+
+	wantErr           error
+	wantState         string
+	wantStatusReqSent bool
+	wantReqIncreased  bool
+	wantNewBlocks     []int64
+	wantRemovedPeers  []p2p.ID
+}
+
+// ---------------------------------------------------------------------------
+// helper test function for different FSM events, state and expected behavior
+func sStopFSMEv(current, expected string) fsmStepTestValues {
+	return fsmStepTestValues{
+		currentState: current,
+		event:        stopFSMEv,
+		wantState:    expected,
+		wantErr:      errNoErrorFinished}
+}
+
+func sUnknownFSMEv(current string) fsmStepTestValues {
+	return fsmStepTestValues{
+		currentState: current,
+		event:        1234,
+		wantState:    current,
+		wantErr:      errInvalidEvent}
+}
+
+func sStartFSMEv() fsmStepTestValues {
+	return fsmStepTestValues{
+		currentState:      "unknown",
+		event:             startFSMEv,
+		wantState:         "waitForPeer",
+		wantStatusReqSent: true}
+}
+
+func sStateTimeoutEv(current, expected string, timedoutState string, wantErr error) fsmStepTestValues {
+	return fsmStepTestValues{
+		currentState: current,
+		event:        stateTimeoutEv,
+		data: bReactorEventData{
+			stateName: timedoutState,
+		},
+		wantState: expected,
+		wantErr:   wantErr,
+	}
+}
+
+func sProcessedBlockEv(current, expected string, reactorError error) fsmStepTestValues {
+	return fsmStepTestValues{
+		currentState: current,
+		event:        processedBlockEv,
+		data: bReactorEventData{
+			err: reactorError,
+		},
+		wantState: expected,
+		wantErr:   reactorError,
+	}
+}
+
+func sStatusEv(current, expected string, peerID p2p.ID, height int64, err error) fsmStepTestValues {
+	return fsmStepTestValues{
+		currentState: current,
+		event:        statusResponseEv,
+		data:         bReactorEventData{peerID: peerID, height: height},
+		wantState:    expected,
+		wantErr:      err}
+}
+
+func sMakeRequestsEv(current, expected string, maxPendingRequests int) fsmStepTestValues {
+	return fsmStepTestValues{
+		currentState:     current,
+		event:            makeRequestsEv,
+		data:             bReactorEventData{maxNumRequests: maxPendingRequests},
+		wantState:        expected,
+		wantReqIncreased: true,
+	}
+}
+
+func sMakeRequestsEvErrored(current, expected string,
+	maxPendingRequests int, err error, peersRemoved []p2p.ID) fsmStepTestValues {
+	return fsmStepTestValues{
+		currentState:     current,
+		event:            makeRequestsEv,
+		data:             bReactorEventData{maxNumRequests: maxPendingRequests},
+		wantState:        expected,
+		wantErr:          err,
+		wantRemovedPeers: peersRemoved,
+		wantReqIncreased: true,
+	}
+}
+
+func sBlockRespEv(current, expected string, peerID p2p.ID, height int64, prevBlocks []int64) fsmStepTestValues {
+	txs := []types.Tx{types.Tx("foo"), types.Tx("bar")}
+	return fsmStepTestValues{
+		currentState: current,
+		event:        blockResponseEv,
+		data: bReactorEventData{
+			peerID: peerID,
+			height: height,
+			block:  types.MakeBlock(height, txs, nil, nil),
+			length: 100},
+		wantState:     expected,
+		wantNewBlocks: append(prevBlocks, height),
+	}
+}
+
+func sBlockRespEvErrored(current, expected string,
+	peerID p2p.ID, height int64, prevBlocks []int64, wantErr error, peersRemoved []p2p.ID) fsmStepTestValues {
+	txs := []types.Tx{types.Tx("foo"), types.Tx("bar")}
+
+	return fsmStepTestValues{
+		currentState: current,
+		event:        blockResponseEv,
+		data: bReactorEventData{
+			peerID: peerID,
+			height: height,
+			block:  types.MakeBlock(height, txs, nil, nil),
+			length: 100},
+		wantState:        expected,
+		wantErr:          wantErr,
+		wantRemovedPeers: peersRemoved,
+		wantNewBlocks:    prevBlocks,
+	}
+}
+
+func sPeerRemoveEv(current, expected string, peerID p2p.ID, err error, peersRemoved []p2p.ID) fsmStepTestValues {
+	return fsmStepTestValues{
+		currentState: current,
+		event:        peerRemoveEv,
+		data: bReactorEventData{
+			peerID: peerID,
+			err:    err,
+		},
+		wantState:        expected,
+		wantRemovedPeers: peersRemoved,
+	}
+}
+
+// --------------------------------------------
+
+func newTestReactor(height int64) *testReactor {
+	testBcR := &testReactor{logger: log.TestingLogger(), stateTimerStarts: make(map[string]int)}
+	testBcR.fsm = NewFSM(height, testBcR)
+	testBcR.fsm.SetLogger(testBcR.logger)
+	return testBcR
+}
+
+func fixBlockResponseEvStep(step *fsmStepTestValues, testBcR *testReactor) {
+	// There is currently no good way to know to which peer a block request was sent.
+	// So in some cases where it does not matter, before we simulate a block response
+	// we cheat and look where it is expected from.
+	if step.event == blockResponseEv {
+		height := step.data.height
+		peerID, ok := testBcR.fsm.pool.blocks[height]
+		if ok {
+			step.data.peerID = peerID
+		}
+	}
+}
+
+type testFields struct {
+	name               string
+	startingHeight     int64
+	maxRequestsPerPeer int
+	maxPendingRequests int
+	steps              []fsmStepTestValues
+}
+
+func executeFSMTests(t *testing.T, tests []testFields, matchRespToReq bool) {
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			// Create test reactor
+			testBcR := newTestReactor(tt.startingHeight)
+
+			if tt.maxRequestsPerPeer != 0 {
+				maxRequestsPerPeer = tt.maxRequestsPerPeer
+			}
+
+			for _, step := range tt.steps {
+				step := step
+				assert.Equal(t, step.currentState, testBcR.fsm.state.name)
+
+				var heightBefore int64
+				if step.event == processedBlockEv && step.data.err == errBlockVerificationFailure {
+					heightBefore = testBcR.fsm.pool.Height
+				}
+				oldNumStatusRequests := testBcR.numStatusRequests
+				oldNumBlockRequests := testBcR.numBlockRequests
+				if matchRespToReq {
+					fixBlockResponseEvStep(&step, testBcR)
+				}
+
+				fsmErr := sendEventToFSM(testBcR.fsm, step.event, step.data)
+				assert.Equal(t, step.wantErr, fsmErr)
+
+				if step.wantStatusReqSent {
+					assert.Equal(t, oldNumStatusRequests+1, testBcR.numStatusRequests)
+				} else {
+					assert.Equal(t, oldNumStatusRequests, testBcR.numStatusRequests)
+				}
+
+				if step.wantReqIncreased {
+					assert.True(t, oldNumBlockRequests < testBcR.numBlockRequests)
+				} else {
+					assert.Equal(t, oldNumBlockRequests, testBcR.numBlockRequests)
+				}
+
+				for _, height := range step.wantNewBlocks {
+					_, err := testBcR.fsm.pool.BlockAndPeerAtHeight(height)
+					assert.Nil(t, err)
+				}
+				if step.event == processedBlockEv && step.data.err == errBlockVerificationFailure {
+					heightAfter := testBcR.fsm.pool.Height
+					assert.Equal(t, heightBefore, heightAfter)
+					firstAfter, err1 := testBcR.fsm.pool.BlockAndPeerAtHeight(testBcR.fsm.pool.Height)
+					secondAfter, err2 := testBcR.fsm.pool.BlockAndPeerAtHeight(testBcR.fsm.pool.Height + 1)
+					assert.NotNil(t, err1)
+					assert.NotNil(t, err2)
+					assert.Nil(t, firstAfter)
+					assert.Nil(t, secondAfter)
+				}
+
+				assert.Equal(t, step.wantState, testBcR.fsm.state.name)
+
+				if step.wantState == "finished" {
+					assert.True(t, testBcR.fsm.isCaughtUp())
+				}
+			}
+		})
+	}
+}
+
+func TestFSMBasic(t *testing.T) {
+	tests := []testFields{
+		{
+			name:               "one block, one peer - TS2",
+			startingHeight:     1,
+			maxRequestsPerPeer: 2,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 2, nil),
+				sMakeRequestsEv("waitForBlock", "waitForBlock", maxNumRequests),
+				sBlockRespEv("waitForBlock", "waitForBlock", "P1", 1, []int64{}),
+				sBlockRespEv("waitForBlock", "waitForBlock", "P2", 2, []int64{1}),
+				sProcessedBlockEv("waitForBlock", "finished", nil),
+			},
+		},
+		{
+			name:               "multi block, multi peer - TS2",
+			startingHeight:     1,
+			maxRequestsPerPeer: 2,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 4, nil),
+				sStatusEv("waitForBlock", "waitForBlock", "P2", 4, nil),
+				sMakeRequestsEv("waitForBlock", "waitForBlock", maxNumRequests),
+
+				sBlockRespEv("waitForBlock", "waitForBlock", "P1", 1, []int64{}),
+				sBlockRespEv("waitForBlock", "waitForBlock", "P1", 2, []int64{1}),
+				sBlockRespEv("waitForBlock", "waitForBlock", "P2", 3, []int64{1, 2}),
+				sBlockRespEv("waitForBlock", "waitForBlock", "P2", 4, []int64{1, 2, 3}),
+
+				sProcessedBlockEv("waitForBlock", "waitForBlock", nil),
+				sProcessedBlockEv("waitForBlock", "waitForBlock", nil),
+				sProcessedBlockEv("waitForBlock", "finished", nil),
+			},
+		},
+	}
+
+	executeFSMTests(t, tests, true)
+}
+
+func TestFSMBlockVerificationFailure(t *testing.T) {
+	tests := []testFields{
+		{
+			name:               "block verification failure - TS2 variant",
+			startingHeight:     1,
+			maxRequestsPerPeer: 3,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+
+				// add P1 and get blocks 1-3 from it
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 3, nil),
+				sMakeRequestsEv("waitForBlock", "waitForBlock", maxNumRequests),
+				sBlockRespEv("waitForBlock", "waitForBlock", "P1", 1, []int64{}),
+				sBlockRespEv("waitForBlock", "waitForBlock", "P1", 2, []int64{1}),
+				sBlockRespEv("waitForBlock", "waitForBlock", "P1", 3, []int64{1, 2}),
+
+				// add P2
+				sStatusEv("waitForBlock", "waitForBlock", "P2", 3, nil),
+
+				// process block failure, should remove P1 and all blocks
+				sProcessedBlockEv("waitForBlock", "waitForBlock", errBlockVerificationFailure),
+
+				// get blocks 1-3 from P2
+				sMakeRequestsEv("waitForBlock", "waitForBlock", maxNumRequests),
+				sBlockRespEv("waitForBlock", "waitForBlock", "P2", 1, []int64{}),
+				sBlockRespEv("waitForBlock", "waitForBlock", "P2", 2, []int64{1}),
+				sBlockRespEv("waitForBlock", "waitForBlock", "P2", 3, []int64{1, 2}),
+
+				// finish after processing blocks 1 and 2
+				sProcessedBlockEv("waitForBlock", "waitForBlock", nil),
+				sProcessedBlockEv("waitForBlock", "finished", nil),
+			},
+		},
+	}
+
+	executeFSMTests(t, tests, false)
+}
+
+func TestFSMBadBlockFromPeer(t *testing.T) {
+	tests := []testFields{
+		{
+			name:               "block we haven't asked for",
+			startingHeight:     1,
+			maxRequestsPerPeer: 3,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				// add P1 and ask for blocks 1-3
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 300, nil),
+				sMakeRequestsEv("waitForBlock", "waitForBlock", maxNumRequests),
+
+				// blockResponseEv for height 100 should cause an error
+				sBlockRespEvErrored("waitForBlock", "waitForPeer",
+					"P1", 100, []int64{}, errMissingBlock, []p2p.ID{}),
+			},
+		},
+		{
+			name:               "block we already have",
+			startingHeight:     1,
+			maxRequestsPerPeer: 3,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				// add P1 and get block 1
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 100, nil),
+				sMakeRequestsEv("waitForBlock", "waitForBlock", maxNumRequests),
+				sBlockRespEv("waitForBlock", "waitForBlock",
+					"P1", 1, []int64{}),
+
+				// Get block 1 again. Since peer is removed together with block 1,
+				// the blocks present in the pool should be {}
+				sBlockRespEvErrored("waitForBlock", "waitForPeer",
+					"P1", 1, []int64{}, errDuplicateBlock, []p2p.ID{"P1"}),
+			},
+		},
+		{
+			name:               "block from unknown peer",
+			startingHeight:     1,
+			maxRequestsPerPeer: 3,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				// add P1 and get block 1
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 3, nil),
+
+				// get block 1 from unknown peer P2
+				sMakeRequestsEv("waitForBlock", "waitForBlock", maxNumRequests),
+				sBlockRespEvErrored("waitForBlock", "waitForBlock",
+					"P2", 1, []int64{}, errBadDataFromPeer, []p2p.ID{"P2"}),
+			},
+		},
+		{
+			name:               "block from wrong peer",
+			startingHeight:     1,
+			maxRequestsPerPeer: 3,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				// add P1, make requests for blocks 1-3 to P1
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 3, nil),
+				sMakeRequestsEv("waitForBlock", "waitForBlock", maxNumRequests),
+
+				// add P2
+				sStatusEv("waitForBlock", "waitForBlock", "P2", 3, nil),
+
+				// receive block 1 from P2
+				sBlockRespEvErrored("waitForBlock", "waitForBlock",
+					"P2", 1, []int64{}, errBadDataFromPeer, []p2p.ID{"P2"}),
+			},
+		},
+	}
+
+	executeFSMTests(t, tests, false)
+}
+
+func TestFSMBlockAtCurrentHeightDoesNotArriveInTime(t *testing.T) {
+	tests := []testFields{
+		{
+			name:               "block at current height undelivered - TS5",
+			startingHeight:     1,
+			maxRequestsPerPeer: 3,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				// add P1, get blocks 1 and 2, process block 1
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 3, nil),
+				sMakeRequestsEv("waitForBlock", "waitForBlock", maxNumRequests),
+				sBlockRespEv("waitForBlock", "waitForBlock",
+					"P1", 1, []int64{}),
+				sBlockRespEv("waitForBlock", "waitForBlock",
+					"P1", 2, []int64{1}),
+				sProcessedBlockEv("waitForBlock", "waitForBlock", nil),
+
+				// add P2
+				sStatusEv("waitForBlock", "waitForBlock", "P2", 3, nil),
+
+				// timeout on block 3, P1 should be removed
+				sStateTimeoutEv("waitForBlock", "waitForBlock", "waitForBlock", errNoPeerResponseForCurrentHeights),
+
+				// make requests and finish by receiving blocks 2 and 3 from P2
+				sMakeRequestsEv("waitForBlock", "waitForBlock", maxNumRequests),
+				sBlockRespEv("waitForBlock", "waitForBlock", "P2", 2, []int64{}),
+				sBlockRespEv("waitForBlock", "waitForBlock", "P2", 3, []int64{2}),
+				sProcessedBlockEv("waitForBlock", "finished", nil),
+			},
+		},
+		{
+			name:               "block at current height undelivered, at maxPeerHeight after peer removal - TS3",
+			startingHeight:     1,
+			maxRequestsPerPeer: 3,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				// add P1, request blocks 1-3 from P1
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 3, nil),
+				sMakeRequestsEv("waitForBlock", "waitForBlock", maxNumRequests),
+
+				// add P2 (tallest)
+				sStatusEv("waitForBlock", "waitForBlock", "P2", 30, nil),
+				sMakeRequestsEv("waitForBlock", "waitForBlock", maxNumRequests),
+
+				// receive blocks 1-3 from P1
+				sBlockRespEv("waitForBlock", "waitForBlock", "P1", 1, []int64{}),
+				sBlockRespEv("waitForBlock", "waitForBlock", "P1", 2, []int64{1}),
+				sBlockRespEv("waitForBlock", "waitForBlock", "P1", 3, []int64{1, 2}),
+
+				// process blocks at heights 1 and 2
+				sProcessedBlockEv("waitForBlock", "waitForBlock", nil),
+				sProcessedBlockEv("waitForBlock", "waitForBlock", nil),
+
+				// timeout on block at height 4
+				sStateTimeoutEv("waitForBlock", "finished", "waitForBlock", nil),
+			},
+		},
+	}
+
+	executeFSMTests(t, tests, true)
+}
+
+func TestFSMPeerRelatedEvents(t *testing.T) {
+	tests := []testFields{
+		{
+			name:           "peer remove event with no blocks",
+			startingHeight: 1,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				// add P1, P2, P3
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 3, nil),
+				sStatusEv("waitForBlock", "waitForBlock", "P2", 3, nil),
+				sStatusEv("waitForBlock", "waitForBlock", "P3", 3, nil),
+
+				// switch removes P2
+				sPeerRemoveEv("waitForBlock", "waitForBlock", "P2", errSwitchRemovesPeer, []p2p.ID{"P2"}),
+			},
+		},
+		{
+			name:           "only peer removed while in waitForBlock state",
+			startingHeight: 100,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				// add P1
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 200, nil),
+
+				// switch removes P1
+				sPeerRemoveEv("waitForBlock", "waitForPeer", "P1", errSwitchRemovesPeer, []p2p.ID{"P1"}),
+			},
+		},
+		{
+			name:               "highest peer removed while in waitForBlock state, node reaches maxPeerHeight - TS4 ",
+			startingHeight:     100,
+			maxRequestsPerPeer: 3,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				// add P1 and make requests
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 101, nil),
+				sMakeRequestsEv("waitForBlock", "waitForBlock", maxNumRequests),
+				// add P2
+				sStatusEv("waitForBlock", "waitForBlock", "P2", 200, nil),
+
+				// get blocks 100 and 101 from P1 and process block at height 100
+				sBlockRespEv("waitForBlock", "waitForBlock", "P1", 100, []int64{}),
+				sBlockRespEv("waitForBlock", "waitForBlock", "P1", 101, []int64{100}),
+				sProcessedBlockEv("waitForBlock", "waitForBlock", nil),
+
+				// switch removes peer P1, should be finished
+				sPeerRemoveEv("waitForBlock", "finished", "P2", errSwitchRemovesPeer, []p2p.ID{"P2"}),
+			},
+		},
+		{
+			name:               "highest peer lowers its height in waitForBlock state, node reaches maxPeerHeight - TS4",
+			startingHeight:     100,
+			maxRequestsPerPeer: 3,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				// add P1 and make requests
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 101, nil),
+				sMakeRequestsEv("waitForBlock", "waitForBlock", maxNumRequests),
+
+				// add P2
+				sStatusEv("waitForBlock", "waitForBlock", "P2", 200, nil),
+
+				// get blocks 100 and 101 from P1
+				sBlockRespEv("waitForBlock", "waitForBlock", "P1", 100, []int64{}),
+				sBlockRespEv("waitForBlock", "waitForBlock", "P1", 101, []int64{100}),
+
+				// processed block at heights 100
+				sProcessedBlockEv("waitForBlock", "waitForBlock", nil),
+
+				// P2 becomes short
+				sStatusEv("waitForBlock", "finished", "P2", 100, errPeerLowersItsHeight),
+			},
+		},
+		{
+			name:           "new short peer while in waitForPeer state",
+			startingHeight: 100,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				sStatusEv("waitForPeer", "waitForPeer", "P1", 3, errPeerTooShort),
+			},
+		},
+		{
+			name:           "new short peer while in waitForBlock state",
+			startingHeight: 100,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 200, nil),
+				sStatusEv("waitForBlock", "waitForBlock", "P2", 3, errPeerTooShort),
+			},
+		},
+		{
+			name:           "only peer updated with low height while in waitForBlock state",
+			startingHeight: 100,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 200, nil),
+				sStatusEv("waitForBlock", "waitForPeer", "P1", 3, errPeerLowersItsHeight),
+			},
+		},
+		{
+			name:               "peer does not exist in the switch",
+			startingHeight:     9999999,
+			maxRequestsPerPeer: 3,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				// add P1
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 20000000, nil),
+				// send request for block 9999999
+				// Note: For this block request the "switch missing the peer" error is simulated,
+				// see implementation of bcReactor interface, sendBlockRequest(), in this file.
+				sMakeRequestsEvErrored("waitForBlock", "waitForBlock",
+					maxNumRequests, nil, []p2p.ID{"P1"}),
+			},
+		},
+	}
+
+	executeFSMTests(t, tests, true)
+}
+
+func TestFSMStopFSM(t *testing.T) {
+	tests := []testFields{
+		{
+			name: "stopFSMEv in unknown",
+			steps: []fsmStepTestValues{
+				sStopFSMEv("unknown", "finished"),
+			},
+		},
+		{
+			name:           "stopFSMEv in waitForPeer",
+			startingHeight: 1,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				sStopFSMEv("waitForPeer", "finished"),
+			},
+		},
+		{
+			name:           "stopFSMEv in waitForBlock",
+			startingHeight: 1,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 3, nil),
+				sStopFSMEv("waitForBlock", "finished"),
+			},
+		},
+	}
+
+	executeFSMTests(t, tests, false)
+}
+
+func TestFSMUnknownElements(t *testing.T) {
+	tests := []testFields{
+		{
+			name: "unknown event for state unknown",
+			steps: []fsmStepTestValues{
+				sUnknownFSMEv("unknown"),
+			},
+		},
+		{
+			name: "unknown event for state waitForPeer",
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				sUnknownFSMEv("waitForPeer"),
+			},
+		},
+		{
+			name:           "unknown event for state waitForBlock",
+			startingHeight: 1,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 3, nil),
+				sUnknownFSMEv("waitForBlock"),
+			},
+		},
+	}
+
+	executeFSMTests(t, tests, false)
+}
+
+func TestFSMPeerStateTimeoutEvent(t *testing.T) {
+	tests := []testFields{
+		{
+			name:               "timeout event for state waitForPeer while in state waitForPeer - TS1",
+			startingHeight:     1,
+			maxRequestsPerPeer: 3,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				sStateTimeoutEv("waitForPeer", "finished", "waitForPeer", errNoTallerPeer),
+			},
+		},
+		{
+			name:               "timeout event for state waitForPeer while in a state != waitForPeer",
+			startingHeight:     1,
+			maxRequestsPerPeer: 3,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				sStateTimeoutEv("waitForPeer", "waitForPeer", "waitForBlock", errTimeoutEventWrongState),
+			},
+		},
+		{
+			name:               "timeout event for state waitForBlock while in state waitForBlock ",
+			startingHeight:     1,
+			maxRequestsPerPeer: 3,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 3, nil),
+				sMakeRequestsEv("waitForBlock", "waitForBlock", maxNumRequests),
+				sStateTimeoutEv("waitForBlock", "waitForPeer", "waitForBlock", errNoPeerResponseForCurrentHeights),
+			},
+		},
+		{
+			name:               "timeout event for state waitForBlock while in a state != waitForBlock",
+			startingHeight:     1,
+			maxRequestsPerPeer: 3,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 3, nil),
+				sMakeRequestsEv("waitForBlock", "waitForBlock", maxNumRequests),
+				sStateTimeoutEv("waitForBlock", "waitForBlock", "waitForPeer", errTimeoutEventWrongState),
+			},
+		},
+		{
+			name:               "timeout event for state waitForBlock with multiple peers",
+			startingHeight:     1,
+			maxRequestsPerPeer: 3,
+			steps: []fsmStepTestValues{
+				sStartFSMEv(),
+				sStatusEv("waitForPeer", "waitForBlock", "P1", 3, nil),
+				sMakeRequestsEv("waitForBlock", "waitForBlock", maxNumRequests),
+				sStatusEv("waitForBlock", "waitForBlock", "P2", 3, nil),
+				sStateTimeoutEv("waitForBlock", "waitForBlock", "waitForBlock", errNoPeerResponseForCurrentHeights),
+			},
+		},
+	}
+
+	executeFSMTests(t, tests, false)
+}
+
+func makeCorrectTransitionSequence(startingHeight int64, numBlocks int64, numPeers int, randomPeerHeights bool,
+	maxRequestsPerPeer int, maxPendingRequests int) testFields {
+
+	// Generate numPeers peers with random or numBlocks heights according to the randomPeerHeights flag.
+	peerHeights := make([]int64, numPeers)
+	for i := 0; i < numPeers; i++ {
+		if i == 0 {
+			peerHeights[0] = numBlocks
+			continue
+		}
+		if randomPeerHeights {
+			peerHeights[i] = int64(tmmath.MaxInt(tmrand.Intn(int(numBlocks)), int(startingHeight)+1))
+		} else {
+			peerHeights[i] = numBlocks
+		}
+	}
+
+	// Approximate the slice capacity to save time for appends.
+	testSteps := make([]fsmStepTestValues, 0, 3*numBlocks+int64(numPeers))
+
+	testName := fmt.Sprintf("%v-blocks %v-startingHeight %v-peers %v-maxRequestsPerPeer %v-maxNumRequests",
+		numBlocks, startingHeight, numPeers, maxRequestsPerPeer, maxPendingRequests)
+
+	// Add startFSMEv step.
+	testSteps = append(testSteps, sStartFSMEv())
+
+	// For each peer, add statusResponseEv step.
+	for i := 0; i < numPeers; i++ {
+		peerName := fmt.Sprintf("P%d", i)
+		if i == 0 {
+			testSteps = append(
+				testSteps,
+				sStatusEv("waitForPeer", "waitForBlock", p2p.ID(peerName), peerHeights[i], nil))
+		} else {
+			testSteps = append(testSteps,
+				sStatusEv("waitForBlock", "waitForBlock", p2p.ID(peerName), peerHeights[i], nil))
+		}
+	}
+
+	height := startingHeight
+	numBlocksReceived := 0
+	prevBlocks := make([]int64, 0, maxPendingRequests)
+
+forLoop:
+	for i := 0; i < int(numBlocks); i++ {
+
+		// Add the makeRequestEv step periodically.
+		if i%maxRequestsPerPeer == 0 {
+			testSteps = append(
+				testSteps,
+				sMakeRequestsEv("waitForBlock", "waitForBlock", maxNumRequests),
+			)
+		}
+
+		// Add the blockRespEv step
+		testSteps = append(
+			testSteps,
+			sBlockRespEv("waitForBlock", "waitForBlock",
+				"P0", height, prevBlocks))
+		prevBlocks = append(prevBlocks, height)
+		height++
+		numBlocksReceived++
+
+		// Add the processedBlockEv step periodically.
+		if numBlocksReceived >= maxRequestsPerPeer || height >= numBlocks {
+			for j := int(height) - numBlocksReceived; j < int(height); j++ {
+				if j >= int(numBlocks) {
+					// This is the last block that is processed, we should be in "finished" state.
+					testSteps = append(
+						testSteps,
+						sProcessedBlockEv("waitForBlock", "finished", nil))
+					break forLoop
+				}
+				testSteps = append(
+					testSteps,
+					sProcessedBlockEv("waitForBlock", "waitForBlock", nil))
+			}
+			numBlocksReceived = 0
+			prevBlocks = make([]int64, 0, maxPendingRequests)
+		}
+	}
+
+	return testFields{
+		name:               testName,
+		startingHeight:     startingHeight,
+		maxRequestsPerPeer: maxRequestsPerPeer,
+		maxPendingRequests: maxPendingRequests,
+		steps:              testSteps,
+	}
+}
+
+const (
+	maxStartingHeightTest       = 100
+	maxRequestsPerPeerTest      = 20
+	maxTotalPendingRequestsTest = 600
+	maxNumPeersTest             = 1000
+	maxNumBlocksInChainTest     = 10000 // should be smaller than 9999999
+)
+
+func makeCorrectTransitionSequenceWithRandomParameters() testFields {
+	// Generate a starting height for fast sync.
+	startingHeight := int64(tmrand.Intn(maxStartingHeightTest) + 1)
+
+	// Generate the number of requests per peer.
+	maxRequestsPerPeer := tmrand.Intn(maxRequestsPerPeerTest) + 1
+
+	// Generate the maximum number of total pending requests, >= maxRequestsPerPeer.
+	maxPendingRequests := tmrand.Intn(maxTotalPendingRequestsTest-maxRequestsPerPeer) + maxRequestsPerPeer
+
+	// Generate the number of blocks to be synced.
+	numBlocks := int64(tmrand.Intn(maxNumBlocksInChainTest)) + startingHeight
+
+	// Generate a number of peers.
+	numPeers := tmrand.Intn(maxNumPeersTest) + 1
+
+	return makeCorrectTransitionSequence(startingHeight, numBlocks, numPeers, true, maxRequestsPerPeer, maxPendingRequests)
+}
+
+func shouldApplyProcessedBlockEvStep(step *fsmStepTestValues, testBcR *testReactor) bool {
+	if step.event == processedBlockEv {
+		_, err := testBcR.fsm.pool.BlockAndPeerAtHeight(testBcR.fsm.pool.Height)
+		if err == errMissingBlock {
+			return false
+		}
+		_, err = testBcR.fsm.pool.BlockAndPeerAtHeight(testBcR.fsm.pool.Height + 1)
+		if err == errMissingBlock {
+			return false
+		}
+	}
+	return true
+}
+
+func TestFSMCorrectTransitionSequences(t *testing.T) {
+
+	tests := []testFields{
+		makeCorrectTransitionSequence(1, 100, 10, true, 10, 40),
+		makeCorrectTransitionSequenceWithRandomParameters(),
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			// Create test reactor
+			testBcR := newTestReactor(tt.startingHeight)
+
+			if tt.maxRequestsPerPeer != 0 {
+				maxRequestsPerPeer = tt.maxRequestsPerPeer
+			}
+
+			for _, step := range tt.steps {
+				step := step
+				assert.Equal(t, step.currentState, testBcR.fsm.state.name)
+
+				oldNumStatusRequests := testBcR.numStatusRequests
+				fixBlockResponseEvStep(&step, testBcR)
+				if !shouldApplyProcessedBlockEvStep(&step, testBcR) {
+					continue
+				}
+
+				fsmErr := sendEventToFSM(testBcR.fsm, step.event, step.data)
+				assert.Equal(t, step.wantErr, fsmErr)
+
+				if step.wantStatusReqSent {
+					assert.Equal(t, oldNumStatusRequests+1, testBcR.numStatusRequests)
+				} else {
+					assert.Equal(t, oldNumStatusRequests, testBcR.numStatusRequests)
+				}
+
+				assert.Equal(t, step.wantState, testBcR.fsm.state.name)
+				if step.wantState == "finished" {
+					assert.True(t, testBcR.fsm.isCaughtUp())
+				}
+			}
+
+		})
+	}
+}
+
+// ----------------------------------------
+// implements the bcRNotifier
+func (testR *testReactor) sendPeerError(err error, peerID p2p.ID) {
+	testR.logger.Info("Reactor received sendPeerError call from FSM", "peer", peerID, "err", err)
+	testR.lastPeerError.peerID = peerID
+	testR.lastPeerError.err = err
+}
+
+func (testR *testReactor) sendStatusRequest() {
+	testR.logger.Info("Reactor received sendStatusRequest call from FSM")
+	testR.numStatusRequests++
+}
+
+func (testR *testReactor) sendBlockRequest(peerID p2p.ID, height int64) error {
+	testR.logger.Info("Reactor received sendBlockRequest call from FSM", "peer", peerID, "height", height)
+	testR.numBlockRequests++
+	testR.lastBlockRequest.peerID = peerID
+	testR.lastBlockRequest.height = height
+	if height == 9999999 {
+		// simulate switch does not have peer
+		return errNilPeerForBlockRequest
+	}
+	return nil
+}
+
+func (testR *testReactor) resetStateTimer(name string, timer **time.Timer, timeout time.Duration) {
+	testR.logger.Info("Reactor received resetStateTimer call from FSM", "state", name, "timeout", timeout)
+	if _, ok := testR.stateTimerStarts[name]; !ok {
+		testR.stateTimerStarts[name] = 1
+	} else {
+		testR.stateTimerStarts[name]++
+	}
+}
+
+func (testR *testReactor) switchToConsensus() {
+}
+
+// ----------------------------------------

blockchain/v1/reactor_test.go

@@ -0,0 +1,390 @@
+package v1
+
+import (
+	"fmt"
+	"os"
+	"sort"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/gogo/protobuf/proto"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	dbm "github.com/tendermint/tm-db"
+
+	abci "github.com/tendermint/tendermint/abci/types"
+	cfg "github.com/tendermint/tendermint/config"
+	"github.com/tendermint/tendermint/libs/log"
+	"github.com/tendermint/tendermint/mempool/mock"
+	"github.com/tendermint/tendermint/p2p"
+	bcproto "github.com/tendermint/tendermint/proto/tendermint/blockchain"
+	tmproto "github.com/tendermint/tendermint/proto/tendermint/types"
+	"github.com/tendermint/tendermint/proxy"
+	sm "github.com/tendermint/tendermint/state"
+	"github.com/tendermint/tendermint/store"
+	"github.com/tendermint/tendermint/types"
+	tmtime "github.com/tendermint/tendermint/types/time"
+)
+
+var config *cfg.Config
+
+func randGenesisDoc(numValidators int, randPower bool, minPower int64) (*types.GenesisDoc, []types.PrivValidator) {
+	validators := make([]types.GenesisValidator, numValidators)
+	privValidators := make([]types.PrivValidator, numValidators)
+	for i := 0; i < numValidators; i++ {
+		val, privVal := types.RandValidator(randPower, minPower)
+		validators[i] = types.GenesisValidator{
+			PubKey: val.PubKey,
+			Power:  val.VotingPower,
+		}
+		privValidators[i] = privVal
+	}
+	sort.Sort(types.PrivValidatorsByAddress(privValidators))
+
+	return &types.GenesisDoc{
+		GenesisTime: tmtime.Now(),
+		ChainID:     config.ChainID(),
+		Validators:  validators,
+	}, privValidators
+}
+
+func makeVote(
+	t *testing.T,
+	header *types.Header,
+	blockID types.BlockID,
+	valset *types.ValidatorSet,
+	privVal types.PrivValidator) *types.Vote {
+
+	pubKey, err := privVal.GetPubKey()
+	require.NoError(t, err)
+
+	valIdx, _ := valset.GetByAddress(pubKey.Address())
+	vote := &types.Vote{
+		ValidatorAddress: pubKey.Address(),
+		ValidatorIndex:   valIdx,
+		Height:           header.Height,
+		Round:            1,
+		Timestamp:        tmtime.Now(),
+		Type:             tmproto.PrecommitType,
+		BlockID:          blockID,
+	}
+
+	vpb := vote.ToProto()
+
+	_ = privVal.SignVote(header.ChainID, vpb)
+	vote.Signature = vpb.Signature
+
+	return vote
+}
+
+type BlockchainReactorPair struct {
+	bcR  *BlockchainReactor
+	conR *consensusReactorTest
+}
+
+func newBlockchainReactor(
+	t *testing.T,
+	logger log.Logger,
+	genDoc *types.GenesisDoc,
+	privVals []types.PrivValidator,
+	maxBlockHeight int64) *BlockchainReactor {
+	if len(privVals) != 1 {
+		panic("only support one validator")
+	}
+
+	app := &testApp{}
+	cc := proxy.NewLocalClientCreator(app)
+	proxyApp := proxy.NewAppConns(cc)
+	err := proxyApp.Start()
+	if err != nil {
+		panic(fmt.Errorf("error start app: %w", err))
+	}
+
+	blockDB := dbm.NewMemDB()
+	stateDB := dbm.NewMemDB()
+	stateStore := sm.NewStore(stateDB, sm.StoreOptions{
+		DiscardABCIResponses: false,
+	})
+	blockStore := store.NewBlockStore(blockDB)
+
+	state, err := stateStore.LoadFromDBOrGenesisDoc(genDoc)
+	if err != nil {
+		panic(fmt.Errorf("error constructing state from genesis file: %w", err))
+	}
+
+	// Make the BlockchainReactor itself.
+	// NOTE we have to create and commit the blocks first because
+	// pool.height is determined from the store.
+	fastSync := true
+	db := dbm.NewMemDB()
+	stateStore = sm.NewStore(db, sm.StoreOptions{
+		DiscardABCIResponses: false,
+	})
+	blockExec := sm.NewBlockExecutor(stateStore, log.TestingLogger(), proxyApp.Consensus(),
+		mock.Mempool{}, sm.EmptyEvidencePool{})
+	if err = stateStore.Save(state); err != nil {
+		panic(err)
+	}
+
+	// let's add some blocks in
+	for blockHeight := int64(1); blockHeight <= maxBlockHeight; blockHeight++ {
+		lastCommit := types.NewCommit(blockHeight-1, 1, types.BlockID{}, nil)
+		if blockHeight > 1 {
+			lastBlockMeta := blockStore.LoadBlockMeta(blockHeight - 1)
+			lastBlock := blockStore.LoadBlock(blockHeight - 1)
+
+			vote := makeVote(t, &lastBlock.Header, lastBlockMeta.BlockID, state.Validators, privVals[0])
+			lastCommit = types.NewCommit(vote.Height, vote.Round, lastBlockMeta.BlockID, []types.CommitSig{vote.CommitSig()})
+		}
+
+		thisBlock := makeBlock(blockHeight, state, lastCommit)
+
+		thisParts := thisBlock.MakePartSet(types.BlockPartSizeBytes)
+		blockID := types.BlockID{Hash: thisBlock.Hash(), PartSetHeader: thisParts.Header()}
+
+		state, _, err = blockExec.ApplyBlock(state, blockID, thisBlock)
+		if err != nil {
+			panic(fmt.Errorf("error apply block: %w", err))
+		}
+
+		blockStore.SaveBlock(thisBlock, thisParts, lastCommit)
+	}
+
+	bcReactor := NewBlockchainReactor(state.Copy(), blockExec, blockStore, fastSync)
+	bcReactor.SetLogger(logger.With("module", "blockchain"))
+
+	return bcReactor
+}
+
+func newBlockchainReactorPair(
+	t *testing.T,
+	logger log.Logger,
+	genDoc *types.GenesisDoc,
+	privVals []types.PrivValidator,
+	maxBlockHeight int64) BlockchainReactorPair {
+
+	consensusReactor := &consensusReactorTest{}
+	consensusReactor.BaseReactor = *p2p.NewBaseReactor("Consensus reactor", consensusReactor)
+
+	return BlockchainReactorPair{
+		newBlockchainReactor(t, logger, genDoc, privVals, maxBlockHeight),
+		consensusReactor}
+}
+
+type consensusReactorTest struct {
+	p2p.BaseReactor     // BaseService + p2p.Switch
+	switchedToConsensus bool
+	mtx                 sync.Mutex
+}
+
+func (conR *consensusReactorTest) SwitchToConsensus(state sm.State, blocksSynced bool) {
+	conR.mtx.Lock()
+	defer conR.mtx.Unlock()
+	conR.switchedToConsensus = true
+}
+
+func TestFastSyncNoBlockResponse(t *testing.T) {
+
+	config = cfg.ResetTestRoot("blockchain_new_reactor_test")
+	defer os.RemoveAll(config.RootDir)
+	genDoc, privVals := randGenesisDoc(1, false, 30)
+
+	maxBlockHeight := int64(65)
+
+	reactorPairs := make([]BlockchainReactorPair, 2)
+
+	logger := log.TestingLogger()
+	reactorPairs[0] = newBlockchainReactorPair(t, logger, genDoc, privVals, maxBlockHeight)
+	reactorPairs[1] = newBlockchainReactorPair(t, logger, genDoc, privVals, 0)
+
+	p2p.MakeConnectedSwitches(config.P2P, 2, func(i int, s *p2p.Switch) *p2p.Switch {
+		s.AddReactor("BLOCKCHAIN", reactorPairs[i].bcR)
+		s.AddReactor("CONSENSUS", reactorPairs[i].conR)
+		moduleName := fmt.Sprintf("blockchain-%v", i)
+		reactorPairs[i].bcR.SetLogger(logger.With("module", moduleName))
+
+		return s
+
+	}, p2p.Connect2Switches)
+
+	defer func() {
+		for _, r := range reactorPairs {
+			_ = r.bcR.Stop()
+			_ = r.conR.Stop()
+		}
+	}()
+
+	tests := []struct {
+		height   int64
+		existent bool
+	}{
+		{maxBlockHeight + 2, false},
+		{10, true},
+		{1, true},
+		{maxBlockHeight + 100, false},
+	}
+
+	for {
+		time.Sleep(10 * time.Millisecond)
+		reactorPairs[1].conR.mtx.Lock()
+		if reactorPairs[1].conR.switchedToConsensus {
+			reactorPairs[1].conR.mtx.Unlock()
+			break
+		}
+		reactorPairs[1].conR.mtx.Unlock()
+	}
+
+	assert.Equal(t, maxBlockHeight, reactorPairs[0].bcR.store.Height())
+
+	for _, tt := range tests {
+		block := reactorPairs[1].bcR.store.LoadBlock(tt.height)
+		if tt.existent {
+			assert.True(t, block != nil)
+		} else {
+			assert.True(t, block == nil)
+		}
+	}
+}
+
+// NOTE: This is too hard to test without
+// an easy way to add test peer to switch
+// or without significant refactoring of the module.
+// Alternatively we could actually dial a TCP conn but
+// that seems extreme.
+func TestFastSyncBadBlockStopsPeer(t *testing.T) {
+	numNodes := 4
+	maxBlockHeight := int64(148)
+
+	config = cfg.ResetTestRoot("blockchain_reactor_test")
+	defer os.RemoveAll(config.RootDir)
+	genDoc, privVals := randGenesisDoc(1, false, 30)
+
+	otherChain := newBlockchainReactorPair(t, log.TestingLogger(), genDoc, privVals, maxBlockHeight)
+	defer func() {
+		_ = otherChain.bcR.Stop()
+		_ = otherChain.conR.Stop()
+	}()
+
+	reactorPairs := make([]BlockchainReactorPair, numNodes)
+	logger := make([]log.Logger, numNodes)
+
+	for i := 0; i < numNodes; i++ {
+		logger[i] = log.TestingLogger()
+		height := int64(0)
+		if i == 0 {
+			height = maxBlockHeight
+		}
+		reactorPairs[i] = newBlockchainReactorPair(t, logger[i], genDoc, privVals, height)
+	}
+
+	switches := p2p.MakeConnectedSwitches(config.P2P, numNodes, func(i int, s *p2p.Switch) *p2p.Switch {
+		reactorPairs[i].conR.mtx.Lock()
+		s.AddReactor("BLOCKCHAIN", reactorPairs[i].bcR)
+		s.AddReactor("CONSENSUS", reactorPairs[i].conR)
+		moduleName := fmt.Sprintf("blockchain-%v", i)
+		reactorPairs[i].bcR.SetLogger(logger[i].With("module", moduleName))
+		reactorPairs[i].conR.mtx.Unlock()
+		return s
+
+	}, p2p.Connect2Switches)
+
+	defer func() {
+		for _, r := range reactorPairs {
+			_ = r.bcR.Stop()
+			_ = r.conR.Stop()
+		}
+	}()
+
+outerFor:
+	for {
+		time.Sleep(10 * time.Millisecond)
+		for i := 0; i < numNodes; i++ {
+			reactorPairs[i].conR.mtx.Lock()
+			if !reactorPairs[i].conR.switchedToConsensus {
+				reactorPairs[i].conR.mtx.Unlock()
+				continue outerFor
+			}
+			reactorPairs[i].conR.mtx.Unlock()
+		}
+		break
+	}
+
+	// at this time, reactors[0-3] is the newest
+	assert.Equal(t, numNodes-1, reactorPairs[1].bcR.Switch.Peers().Size())
+
+	// mark last reactorPair as an invalid peer
+	reactorPairs[numNodes-1].bcR.store = otherChain.bcR.store
+
+	lastLogger := log.TestingLogger()
+	lastReactorPair := newBlockchainReactorPair(t, lastLogger, genDoc, privVals, 0)
+	reactorPairs = append(reactorPairs, lastReactorPair)
+
+	switches = append(switches, p2p.MakeConnectedSwitches(config.P2P, 1, func(i int, s *p2p.Switch) *p2p.Switch {
+		s.AddReactor("BLOCKCHAIN", reactorPairs[len(reactorPairs)-1].bcR)
+		s.AddReactor("CONSENSUS", reactorPairs[len(reactorPairs)-1].conR)
+		moduleName := fmt.Sprintf("blockchain-%v", len(reactorPairs)-1)
+		reactorPairs[len(reactorPairs)-1].bcR.SetLogger(lastLogger.With("module", moduleName))
+		return s
+
+	}, p2p.Connect2Switches)...)
+
+	for i := 0; i < len(reactorPairs)-1; i++ {
+		p2p.Connect2Switches(switches, i, len(reactorPairs)-1)
+	}
+
+	for {
+		time.Sleep(1 * time.Second)
+		lastReactorPair.conR.mtx.Lock()
+		if lastReactorPair.conR.switchedToConsensus {
+			lastReactorPair.conR.mtx.Unlock()
+			break
+		}
+		lastReactorPair.conR.mtx.Unlock()
+
+		if lastReactorPair.bcR.Switch.Peers().Size() == 0 {
+			break
+		}
+	}
+
+	assert.True(t, lastReactorPair.bcR.Switch.Peers().Size() < len(reactorPairs)-1)
+}
+
+func TestLegacyReactorReceiveBasic(t *testing.T) {
+	config = cfg.ResetTestRoot("blockchain_reactor_test")
+	defer os.RemoveAll(config.RootDir)
+	genDoc, privVals := randGenesisDoc(1, false, 30)
+	reactor := newBlockchainReactor(t, log.TestingLogger(), genDoc, privVals, 10)
+	peer := p2p.CreateRandomPeer(false)
+
+	reactor.InitPeer(peer)
+	reactor.AddPeer(peer)
+	m := &bcproto.StatusRequest{}
+	wm := m.Wrap()
+	msg, err := proto.Marshal(wm)
+	assert.NoError(t, err)
+
+	assert.NotPanics(t, func() {
+		reactor.Receive(BlockchainChannel, peer, msg)
+	})
+}
+
+//----------------------------------------------
+// utility funcs
+
+func makeTxs(height int64) (txs []types.Tx) {
+	for i := 0; i < 10; i++ {
+		txs = append(txs, types.Tx([]byte{byte(height), byte(i)}))
+	}
+	return txs
+}
+
+func makeBlock(height int64, state sm.State, lastCommit *types.Commit) *types.Block {
+	block, _ := state.MakeBlock(height, makeTxs(height), lastCommit, nil, state.Validators.GetProposer().Address)
+	return block
+}
+
+type testApp struct {
+	abci.BaseApplication
+}

blockchain/v2/io.go

@@ -0,0 +1,127 @@
+package v2
+
+import (
+	"fmt"
+
+	"github.com/tendermint/tendermint/p2p"
+	bcproto "github.com/tendermint/tendermint/proto/tendermint/blockchain"
+	"github.com/tendermint/tendermint/state"
+	"github.com/tendermint/tendermint/types"
+)
+
+type iIO interface {
+	sendBlockRequest(peerID p2p.ID, height int64) error
+	sendBlockToPeer(block *types.Block, peerID p2p.ID) error
+	sendBlockNotFound(height int64, peerID p2p.ID) error
+	sendStatusResponse(base, height int64, peerID p2p.ID) error
+
+	broadcastStatusRequest()
+
+	trySwitchToConsensus(state state.State, skipWAL bool) bool
+}
+
+type switchIO struct {
+	sw *p2p.Switch
+}
+
+func newSwitchIo(sw *p2p.Switch) *switchIO {
+	return &switchIO{
+		sw: sw,
+	}
+}
+
+const (
+	// BlockchainChannel is a channel for blocks and status updates (`BlockStore` height)
+	BlockchainChannel = byte(0x40)
+)
+
+type consensusReactor interface {
+	// for when we switch from blockchain reactor and fast sync to
+	// the consensus machine
+	SwitchToConsensus(state state.State, skipWAL bool)
+}
+
+func (sio *switchIO) sendBlockRequest(peerID p2p.ID, height int64) error {
+	peer := sio.sw.Peers().Get(peerID)
+	if peer == nil {
+		return fmt.Errorf("peer not found")
+	}
+	if queued := p2p.TrySendEnvelopeShim(peer, p2p.Envelope{ //nolint: staticcheck
+		ChannelID: BlockchainChannel,
+		Message:   &bcproto.BlockRequest{Height: height},
+	}, sio.sw.Logger); !queued {
+		return fmt.Errorf("send queue full")
+	}
+	return nil
+}
+
+func (sio *switchIO) sendStatusResponse(base int64, height int64, peerID p2p.ID) error {
+	peer := sio.sw.Peers().Get(peerID)
+	if peer == nil {
+		return fmt.Errorf("peer not found")
+	}
+
+	if queued := p2p.TrySendEnvelopeShim(peer, p2p.Envelope{ //nolint: staticcheck
+		ChannelID: BlockchainChannel,
+		Message:   &bcproto.StatusRequest{},
+	}, sio.sw.Logger); !queued {
+		return fmt.Errorf("peer queue full")
+	}
+
+	return nil
+}
+
+func (sio *switchIO) sendBlockToPeer(block *types.Block, peerID p2p.ID) error {
+	peer := sio.sw.Peers().Get(peerID)
+	if peer == nil {
+		return fmt.Errorf("peer not found")
+	}
+	if block == nil {
+		panic("trying to send nil block")
+	}
+
+	bpb, err := block.ToProto()
+	if err != nil {
+		return err
+	}
+
+	if queued := p2p.TrySendEnvelopeShim(peer, p2p.Envelope{ //nolint: staticcheck
+		ChannelID: BlockchainChannel,
+		Message:   &bcproto.BlockResponse{Block: bpb},
+	}, sio.sw.Logger); !queued {
+		return fmt.Errorf("peer queue full")
+	}
+
+	return nil
+}
+
+func (sio *switchIO) sendBlockNotFound(height int64, peerID p2p.ID) error {
+	peer := sio.sw.Peers().Get(peerID)
+	if peer == nil {
+		return fmt.Errorf("peer not found")
+	}
+	if queued := p2p.TrySendEnvelopeShim(peer, p2p.Envelope{ //nolint: staticcheck
+		ChannelID: BlockchainChannel,
+		Message:   &bcproto.NoBlockResponse{Height: height},
+	}, sio.sw.Logger); !queued {
+		return fmt.Errorf("peer queue full")
+	}
+
+	return nil
+}
+
+func (sio *switchIO) trySwitchToConsensus(state state.State, skipWAL bool) bool {
+	conR, ok := sio.sw.Reactor("CONSENSUS").(consensusReactor)
+	if ok {
+		conR.SwitchToConsensus(state, skipWAL)
+	}
+	return ok
+}
+
+func (sio *switchIO) broadcastStatusRequest() {
+	// XXX: maybe we should use an io specific peer list here
+	sio.sw.BroadcastEnvelope(p2p.Envelope{
+		ChannelID: BlockchainChannel,
+		Message:   &bcproto.StatusRequest{},
+	})
+}

blockchain/v2/metrics.go

@@ -0,0 +1,125 @@
+package v2
+
+import (
+	"github.com/go-kit/kit/metrics"
+	"github.com/go-kit/kit/metrics/discard"
+	"github.com/go-kit/kit/metrics/prometheus"
+	stdprometheus "github.com/prometheus/client_golang/prometheus"
+)
+
+const (
+	// MetricsSubsystem is a subsystem shared by all metrics exposed by this
+	// package.
+	MetricsSubsystem = "blockchain"
+)
+
+// Metrics contains metrics exposed by this package.
+type Metrics struct {
+	// events_in
+	EventsIn metrics.Counter
+	// events_in
+	EventsHandled metrics.Counter
+	// events_out
+	EventsOut metrics.Counter
+	// errors_in
+	ErrorsIn metrics.Counter
+	// errors_handled
+	ErrorsHandled metrics.Counter
+	// errors_out
+	ErrorsOut metrics.Counter
+	// events_shed
+	EventsShed metrics.Counter
+	// events_sent
+	EventsSent metrics.Counter
+	// errors_sent
+	ErrorsSent metrics.Counter
+	// errors_shed
+	ErrorsShed metrics.Counter
+}
+
+// PrometheusMetrics returns metrics for in and out events, errors, etc. handled by routines.
+// Can we burn in the routine name here?
+func PrometheusMetrics(namespace string, labelsAndValues ...string) *Metrics {
+	labels := []string{}
+	for i := 0; i < len(labelsAndValues); i += 2 {
+		labels = append(labels, labelsAndValues[i])
+	}
+	return &Metrics{
+		EventsIn: prometheus.NewCounterFrom(stdprometheus.CounterOpts{
+			Namespace: namespace,
+			Subsystem: MetricsSubsystem,
+			Name:      "events_in",
+			Help:      "Events read from the channel.",
+		}, labels).With(labelsAndValues...),
+		EventsHandled: prometheus.NewCounterFrom(stdprometheus.CounterOpts{
+			Namespace: namespace,
+			Subsystem: MetricsSubsystem,
+			Name:      "events_handled",
+			Help:      "Events handled",
+		}, labels).With(labelsAndValues...),
+		EventsOut: prometheus.NewCounterFrom(stdprometheus.CounterOpts{
+			Namespace: namespace,
+			Subsystem: MetricsSubsystem,
+			Name:      "events_out",
+			Help:      "Events output from routine.",
+		}, labels).With(labelsAndValues...),
+		ErrorsIn: prometheus.NewCounterFrom(stdprometheus.CounterOpts{
+			Namespace: namespace,
+			Subsystem: MetricsSubsystem,
+			Name:      "errors_in",
+			Help:      "Errors read from the channel.",
+		}, labels).With(labelsAndValues...),
+		ErrorsHandled: prometheus.NewCounterFrom(stdprometheus.CounterOpts{
+			Namespace: namespace,
+			Subsystem: MetricsSubsystem,
+			Name:      "errors_handled",
+			Help:      "Errors handled.",
+		}, labels).With(labelsAndValues...),
+		ErrorsOut: prometheus.NewCounterFrom(stdprometheus.CounterOpts{
+			Namespace: namespace,
+			Subsystem: MetricsSubsystem,
+			Name:      "errors_out",
+			Help:      "Errors output from routine.",
+		}, labels).With(labelsAndValues...),
+		ErrorsSent: prometheus.NewCounterFrom(stdprometheus.CounterOpts{
+			Namespace: namespace,
+			Subsystem: MetricsSubsystem,
+			Name:      "errors_sent",
+			Help:      "Errors sent to routine.",
+		}, labels).With(labelsAndValues...),
+		ErrorsShed: prometheus.NewCounterFrom(stdprometheus.CounterOpts{
+			Namespace: namespace,
+			Subsystem: MetricsSubsystem,
+			Name:      "errors_shed",
+			Help:      "Errors dropped from sending.",
+		}, labels).With(labelsAndValues...),
+		EventsSent: prometheus.NewCounterFrom(stdprometheus.CounterOpts{
+			Namespace: namespace,
+			Subsystem: MetricsSubsystem,
+			Name:      "events_sent",
+			Help:      "Events sent to routine.",
+		}, labels).With(labelsAndValues...),
+		EventsShed: prometheus.NewCounterFrom(stdprometheus.CounterOpts{
+			Namespace: namespace,
+			Subsystem: MetricsSubsystem,
+			Name:      "events_shed",
+			Help:      "Events dropped from sending.",
+		}, labels).With(labelsAndValues...),
+	}
+}
+
+// NopMetrics returns no-op Metrics.
+func NopMetrics() *Metrics {
+	return &Metrics{
+		EventsIn:      discard.NewCounter(),
+		EventsHandled: discard.NewCounter(),
+		EventsOut:     discard.NewCounter(),
+		ErrorsIn:      discard.NewCounter(),
+		ErrorsHandled: discard.NewCounter(),
+		ErrorsOut:     discard.NewCounter(),
+		EventsShed:    discard.NewCounter(),
+		EventsSent:    discard.NewCounter(),
+		ErrorsSent:    discard.NewCounter(),
+		ErrorsShed:    discard.NewCounter(),
+	}
+}

blockchain/v2/processor.go

@@ -0,0 +1,192 @@
+package v2
+
+import (
+	"fmt"
+
+	"github.com/tendermint/tendermint/p2p"
+	tmState "github.com/tendermint/tendermint/state"
+	"github.com/tendermint/tendermint/types"
+)
+
+// Events generated by the processor:
+// block execution failure, event will indicate the peer(s) that caused the error
+type pcBlockVerificationFailure struct {
+	priorityNormal
+	height       int64
+	firstPeerID  p2p.ID
+	secondPeerID p2p.ID
+}
+
+func (e pcBlockVerificationFailure) String() string {
+	return fmt.Sprintf("pcBlockVerificationFailure{%d 1st peer: %v, 2nd peer: %v}",
+		e.height, e.firstPeerID, e.secondPeerID)
+}
+
+// successful block execution
+type pcBlockProcessed struct {
+	priorityNormal
+	height int64
+	peerID p2p.ID
+}
+
+func (e pcBlockProcessed) String() string {
+	return fmt.Sprintf("pcBlockProcessed{%d peer: %v}", e.height, e.peerID)
+}
+
+// processor has finished
+type pcFinished struct {
+	priorityNormal
+	blocksSynced int
+	tmState      tmState.State
+}
+
+func (p pcFinished) Error() string {
+	return "finished"
+}
+
+type queueItem struct {
+	block  *types.Block
+	peerID p2p.ID
+}
+
+type blockQueue map[int64]queueItem
+
+type pcState struct {
+	// blocks waiting to be processed
+	queue blockQueue
+
+	// draining indicates that the next rProcessBlock event with a queue miss constitutes completion
+	draining bool
+
+	// the number of blocks successfully synced by the processor
+	blocksSynced int
+
+	// the processorContext which contains the processor dependencies
+	context processorContext
+}
+
+func (state *pcState) String() string {
+	return fmt.Sprintf("height: %d queue length: %d draining: %v blocks synced: %d",
+		state.height(), len(state.queue), state.draining, state.blocksSynced)
+}
+
+// newPcState returns a pcState initialized with the last verified block enqueued
+func newPcState(context processorContext) *pcState {
+	return &pcState{
+		queue:        blockQueue{},
+		draining:     false,
+		blocksSynced: 0,
+		context:      context,
+	}
+}
+
+// nextTwo returns the next two unverified blocks
+func (state *pcState) nextTwo() (queueItem, queueItem, error) {
+	if first, ok := state.queue[state.height()+1]; ok {
+		if second, ok := state.queue[state.height()+2]; ok {
+			return first, second, nil
+		}
+	}
+	return queueItem{}, queueItem{}, fmt.Errorf("not found")
+}
+
+// synced returns true when at most the last verified block remains in the queue
+func (state *pcState) synced() bool {
+	return len(state.queue) <= 1
+}
+
+func (state *pcState) enqueue(peerID p2p.ID, block *types.Block, height int64) {
+	if item, ok := state.queue[height]; ok {
+		panic(fmt.Sprintf(
+			"duplicate block %d (%X) enqueued by processor (sent by %v; existing block %X from %v)",
+			height, block.Hash(), peerID, item.block.Hash(), item.peerID))
+	}
+
+	state.queue[height] = queueItem{block: block, peerID: peerID}
+}
+
+func (state *pcState) height() int64 {
+	return state.context.tmState().LastBlockHeight
+}
+
+// purgePeer moves all unprocessed blocks from the queue
+func (state *pcState) purgePeer(peerID p2p.ID) {
+	// what if height is less than state.height?
+	for height, item := range state.queue {
+		if item.peerID == peerID {
+			delete(state.queue, height)
+		}
+	}
+}
+
+// handle processes FSM events
+func (state *pcState) handle(event Event) (Event, error) {
+	switch event := event.(type) {
+	case bcResetState:
+		state.context.setState(event.state)
+		return noOp, nil
+
+	case scFinishedEv:
+		if state.synced() {
+			return pcFinished{tmState: state.context.tmState(), blocksSynced: state.blocksSynced}, nil
+		}
+		state.draining = true
+		return noOp, nil
+
+	case scPeerError:
+		state.purgePeer(event.peerID)
+		return noOp, nil
+
+	case scBlockReceived:
+		if event.block == nil {
+			return noOp, nil
+		}
+
+		// enqueue block if height is higher than state height, else ignore it
+		if event.block.Height > state.height() {
+			state.enqueue(event.peerID, event.block, event.block.Height)
+		}
+		return noOp, nil
+
+	case rProcessBlock:
+		tmState := state.context.tmState()
+		firstItem, secondItem, err := state.nextTwo()
+		if err != nil {
+			if state.draining {
+				return pcFinished{tmState: tmState, blocksSynced: state.blocksSynced}, nil
+			}
+			return noOp, nil
+		}
+
+		var (
+			first, second = firstItem.block, secondItem.block
+			firstParts    = first.MakePartSet(types.BlockPartSizeBytes)
+			firstID       = types.BlockID{Hash: first.Hash(), PartSetHeader: firstParts.Header()}
+		)
+
+		// verify if +second+ last commit "confirms" +first+ block
+		err = state.context.verifyCommit(tmState.ChainID, firstID, first.Height, second.LastCommit)
+		if err != nil {
+			state.purgePeer(firstItem.peerID)
+			if firstItem.peerID != secondItem.peerID {
+				state.purgePeer(secondItem.peerID)
+			}
+			return pcBlockVerificationFailure{
+					height: first.Height, firstPeerID: firstItem.peerID, secondPeerID: secondItem.peerID},
+				nil
+		}
+
+		state.context.saveBlock(first, firstParts, second.LastCommit)
+
+		if err := state.context.applyBlock(firstID, first); err != nil {
+			panic(fmt.Sprintf("failed to process committed block (%d:%X): %v", first.Height, first.Hash(), err))
+		}
+
+		delete(state.queue, first.Height)
+		state.blocksSynced++
+
+		return pcBlockProcessed{height: first.Height, peerID: firstItem.peerID}, nil
+	}
+
+	return noOp, nil
+}

blockchain/v2/processor_context.go

@@ -0,0 +1,100 @@
+package v2
+
+import (
+	"fmt"
+
+	"github.com/tendermint/tendermint/state"
+	"github.com/tendermint/tendermint/types"
+)
+
+type processorContext interface {
+	applyBlock(blockID types.BlockID, block *types.Block) error
+	verifyCommit(chainID string, blockID types.BlockID, height int64, commit *types.Commit) error
+	saveBlock(block *types.Block, blockParts *types.PartSet, seenCommit *types.Commit)
+	tmState() state.State
+	setState(state.State)
+}
+
+type pContext struct {
+	store   blockStore
+	applier blockApplier
+	state   state.State
+}
+
+func newProcessorContext(st blockStore, ex blockApplier, s state.State) *pContext {
+	return &pContext{
+		store:   st,
+		applier: ex,
+		state:   s,
+	}
+}
+
+func (pc *pContext) applyBlock(blockID types.BlockID, block *types.Block) error {
+	newState, _, err := pc.applier.ApplyBlock(pc.state, blockID, block)
+	pc.state = newState
+	return err
+}
+
+func (pc pContext) tmState() state.State {
+	return pc.state
+}
+
+func (pc *pContext) setState(state state.State) {
+	pc.state = state
+}
+
+func (pc pContext) verifyCommit(chainID string, blockID types.BlockID, height int64, commit *types.Commit) error {
+	return pc.state.Validators.VerifyCommitLight(chainID, blockID, height, commit)
+}
+
+func (pc *pContext) saveBlock(block *types.Block, blockParts *types.PartSet, seenCommit *types.Commit) {
+	pc.store.SaveBlock(block, blockParts, seenCommit)
+}
+
+type mockPContext struct {
+	applicationBL  []int64
+	verificationBL []int64
+	state          state.State
+}
+
+func newMockProcessorContext(
+	state state.State,
+	verificationBlackList []int64,
+	applicationBlackList []int64) *mockPContext {
+	return &mockPContext{
+		applicationBL:  applicationBlackList,
+		verificationBL: verificationBlackList,
+		state:          state,
+	}
+}
+
+func (mpc *mockPContext) applyBlock(blockID types.BlockID, block *types.Block) error {
+	for _, h := range mpc.applicationBL {
+		if h == block.Height {
+			return fmt.Errorf("generic application error")
+		}
+	}
+	mpc.state.LastBlockHeight = block.Height
+	return nil
+}
+
+func (mpc *mockPContext) verifyCommit(chainID string, blockID types.BlockID, height int64, commit *types.Commit) error {
+	for _, h := range mpc.verificationBL {
+		if h == height {
+			return fmt.Errorf("generic verification error")
+		}
+	}
+	return nil
+}
+
+func (mpc *mockPContext) saveBlock(block *types.Block, blockParts *types.PartSet, seenCommit *types.Commit) {
+
+}
+
+func (mpc *mockPContext) setState(state state.State) {
+	mpc.state = state
+}
+
+func (mpc *mockPContext) tmState() state.State {
+	return mpc.state
+}

blockchain/v2/processor_test.go

@@ -0,0 +1,306 @@
+package v2
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	"github.com/tendermint/tendermint/p2p"
+	tmState "github.com/tendermint/tendermint/state"
+	"github.com/tendermint/tendermint/types"
+)
+
+// pcBlock is a test helper structure with simple types. Its purpose is to help with test readability.
+type pcBlock struct {
+	pid    string
+	height int64
+}
+
+// params is a test structure used to create processor state.
+type params struct {
+	height       int64
+	items        []pcBlock
+	blocksSynced int
+	verBL        []int64
+	appBL        []int64
+	draining     bool
+}
+
+// makePcBlock makes an empty block.
+func makePcBlock(height int64) *types.Block {
+	return &types.Block{Header: types.Header{Height: height}}
+}
+
+// makeState takes test parameters and creates a specific processor state.
+func makeState(p *params) *pcState {
+	var (
+		tmState = tmState.State{LastBlockHeight: p.height}
+		context = newMockProcessorContext(tmState, p.verBL, p.appBL)
+	)
+	state := newPcState(context)
+
+	for _, item := range p.items {
+		state.enqueue(p2p.ID(item.pid), makePcBlock(item.height), item.height)
+	}
+
+	state.blocksSynced = p.blocksSynced
+	state.draining = p.draining
+	return state
+}
+
+func mBlockResponse(peerID p2p.ID, height int64) scBlockReceived {
+	return scBlockReceived{
+		peerID: peerID,
+		block:  makePcBlock(height),
+	}
+}
+
+type pcFsmMakeStateValues struct {
+	currentState  *params
+	event         Event
+	wantState     *params
+	wantNextEvent Event
+	wantErr       error
+	wantPanic     bool
+}
+
+type testFields struct {
+	name  string
+	steps []pcFsmMakeStateValues
+}
+
+func executeProcessorTests(t *testing.T, tests []testFields) {
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			var state *pcState
+			for _, step := range tt.steps {
+				defer func() {
+					r := recover()
+					if (r != nil) != step.wantPanic {
+						t.Errorf("recover = %v, wantPanic = %v", r, step.wantPanic)
+					}
+				}()
+
+				// First step must always initialise the currentState as state.
+				if step.currentState != nil {
+					state = makeState(step.currentState)
+				}
+				if state == nil {
+					panic("Bad (initial?) step")
+				}
+
+				nextEvent, err := state.handle(step.event)
+				t.Log(state)
+				assert.Equal(t, step.wantErr, err)
+				assert.Equal(t, makeState(step.wantState), state)
+				assert.Equal(t, step.wantNextEvent, nextEvent)
+				// Next step may use the wantedState as their currentState.
+				state = makeState(step.wantState)
+			}
+		})
+	}
+}
+
+func TestRProcessPeerError(t *testing.T) {
+	tests := []testFields{
+		{
+			name: "error for existing peer",
+			steps: []pcFsmMakeStateValues{
+				{
+					currentState:  &params{items: []pcBlock{{"P1", 1}, {"P2", 2}}},
+					event:         scPeerError{peerID: "P2"},
+					wantState:     &params{items: []pcBlock{{"P1", 1}}},
+					wantNextEvent: noOp,
+				},
+			},
+		},
+		{
+			name: "error for unknown peer",
+			steps: []pcFsmMakeStateValues{
+				{
+					currentState:  &params{items: []pcBlock{{"P1", 1}, {"P2", 2}}},
+					event:         scPeerError{peerID: "P3"},
+					wantState:     &params{items: []pcBlock{{"P1", 1}, {"P2", 2}}},
+					wantNextEvent: noOp,
+				},
+			},
+		},
+	}
+
+	executeProcessorTests(t, tests)
+}
+
+func TestPcBlockResponse(t *testing.T) {
+	tests := []testFields{
+		{
+			name: "add one block",
+			steps: []pcFsmMakeStateValues{
+				{
+					currentState: &params{}, event: mBlockResponse("P1", 1),
+					wantState: &params{items: []pcBlock{{"P1", 1}}}, wantNextEvent: noOp,
+				},
+			},
+		},
+
+		{
+			name: "add two blocks",
+			steps: []pcFsmMakeStateValues{
+				{
+					currentState: &params{}, event: mBlockResponse("P1", 3),
+					wantState: &params{items: []pcBlock{{"P1", 3}}}, wantNextEvent: noOp,
+				},
+				{ // use previous wantState as currentState,
+					event:     mBlockResponse("P1", 4),
+					wantState: &params{items: []pcBlock{{"P1", 3}, {"P1", 4}}}, wantNextEvent: noOp,
+				},
+			},
+		},
+	}
+
+	executeProcessorTests(t, tests)
+}
+
+func TestRProcessBlockSuccess(t *testing.T) {
+	tests := []testFields{
+		{
+			name: "noop - no blocks over current height",
+			steps: []pcFsmMakeStateValues{
+				{
+					currentState: &params{}, event: rProcessBlock{},
+					wantState: &params{}, wantNextEvent: noOp,
+				},
+			},
+		},
+		{
+			name: "noop - high new blocks",
+			steps: []pcFsmMakeStateValues{
+				{
+					currentState: &params{height: 5, items: []pcBlock{{"P1", 30}, {"P2", 31}}}, event: rProcessBlock{},
+					wantState: &params{height: 5, items: []pcBlock{{"P1", 30}, {"P2", 31}}}, wantNextEvent: noOp,
+				},
+			},
+		},
+		{
+			name: "blocks H+1 and H+2 present",
+			steps: []pcFsmMakeStateValues{
+				{
+					currentState: &params{items: []pcBlock{{"P1", 1}, {"P2", 2}}}, event: rProcessBlock{},
+					wantState:     &params{height: 1, items: []pcBlock{{"P2", 2}}, blocksSynced: 1},
+					wantNextEvent: pcBlockProcessed{height: 1, peerID: "P1"},
+				},
+			},
+		},
+		{
+			name: "blocks H+1 and H+2 present after draining",
+			steps: []pcFsmMakeStateValues{
+				{ // some contiguous blocks - on stop check draining is set
+					currentState:  &params{items: []pcBlock{{"P1", 1}, {"P2", 2}, {"P1", 4}}},
+					event:         scFinishedEv{},
+					wantState:     &params{items: []pcBlock{{"P1", 1}, {"P2", 2}, {"P1", 4}}, draining: true},
+					wantNextEvent: noOp,
+				},
+				{
+					event:         rProcessBlock{},
+					wantState:     &params{height: 1, items: []pcBlock{{"P2", 2}, {"P1", 4}}, blocksSynced: 1, draining: true},
+					wantNextEvent: pcBlockProcessed{height: 1, peerID: "P1"},
+				},
+				{ // finish when H+1 or/and H+2 are missing
+					event:         rProcessBlock{},
+					wantState:     &params{height: 1, items: []pcBlock{{"P2", 2}, {"P1", 4}}, blocksSynced: 1, draining: true},
+					wantNextEvent: pcFinished{tmState: tmState.State{LastBlockHeight: 1}, blocksSynced: 1},
+				},
+			},
+		},
+	}
+
+	executeProcessorTests(t, tests)
+}
+
+func TestRProcessBlockFailures(t *testing.T) {
+	tests := []testFields{
+		{
+			name: "blocks H+1 and H+2 present from different peers - H+1 verification fails ",
+			steps: []pcFsmMakeStateValues{
+				{
+					currentState: &params{items: []pcBlock{{"P1", 1}, {"P2", 2}}, verBL: []int64{1}}, event: rProcessBlock{},
+					wantState:     &params{items: []pcBlock{}, verBL: []int64{1}},
+					wantNextEvent: pcBlockVerificationFailure{height: 1, firstPeerID: "P1", secondPeerID: "P2"},
+				},
+			},
+		},
+		{
+			name: "blocks H+1 and H+2 present from same peer - H+1 applyBlock fails ",
+			steps: []pcFsmMakeStateValues{
+				{
+					currentState: &params{items: []pcBlock{{"P1", 1}, {"P2", 2}}, appBL: []int64{1}}, event: rProcessBlock{},
+					wantState: &params{items: []pcBlock{}, appBL: []int64{1}}, wantPanic: true,
+				},
+			},
+		},
+		{
+			name: "blocks H+1 and H+2 present from same peers - H+1 verification fails ",
+			steps: []pcFsmMakeStateValues{
+				{
+					currentState: &params{height: 0, items: []pcBlock{{"P1", 1}, {"P1", 2}, {"P2", 3}},
+						verBL: []int64{1}}, event: rProcessBlock{},
+					wantState:     &params{height: 0, items: []pcBlock{{"P2", 3}}, verBL: []int64{1}},
+					wantNextEvent: pcBlockVerificationFailure{height: 1, firstPeerID: "P1", secondPeerID: "P1"},
+				},
+			},
+		},
+		{
+			name: "blocks H+1 and H+2 present from different peers - H+1 applyBlock fails ",
+			steps: []pcFsmMakeStateValues{
+				{
+					currentState: &params{items: []pcBlock{{"P1", 1}, {"P2", 2}, {"P2", 3}}, appBL: []int64{1}},
+					event:        rProcessBlock{},
+					wantState:    &params{items: []pcBlock{{"P2", 3}}, appBL: []int64{1}}, wantPanic: true,
+				},
+			},
+		},
+	}
+
+	executeProcessorTests(t, tests)
+}
+
+func TestScFinishedEv(t *testing.T) {
+	tests := []testFields{
+		{
+			name: "no blocks",
+			steps: []pcFsmMakeStateValues{
+				{
+					currentState: &params{height: 100, items: []pcBlock{}, blocksSynced: 100}, event: scFinishedEv{},
+					wantState:     &params{height: 100, items: []pcBlock{}, blocksSynced: 100},
+					wantNextEvent: pcFinished{tmState: tmState.State{LastBlockHeight: 100}, blocksSynced: 100},
+				},
+			},
+		},
+		{
+			name: "maxHeight+1 block present",
+			steps: []pcFsmMakeStateValues{
+				{
+					currentState: &params{height: 100, items: []pcBlock{
+						{"P1", 101}}, blocksSynced: 100}, event: scFinishedEv{},
+					wantState:     &params{height: 100, items: []pcBlock{{"P1", 101}}, blocksSynced: 100},
+					wantNextEvent: pcFinished{tmState: tmState.State{LastBlockHeight: 100}, blocksSynced: 100},
+				},
+			},
+		},
+		{
+			name: "more blocks present",
+			steps: []pcFsmMakeStateValues{
+				{
+					currentState: &params{height: 100, items: []pcBlock{
+						{"P1", 101}, {"P1", 102}}, blocksSynced: 100}, event: scFinishedEv{},
+					wantState: &params{height: 100, items: []pcBlock{
+						{"P1", 101}, {"P1", 102}}, blocksSynced: 100, draining: true},
+					wantNextEvent: noOp,
+					wantErr:       nil,
+				},
+			},
+		},
+	}
+
+	executeProcessorTests(t, tests)
+}

blockchain/v2/reactor.go

@@ -0,0 +1,574 @@
+package v2
+
+import (
+	"errors"
+	"fmt"
+	"time"
+
+	"github.com/gogo/protobuf/proto"
+
+	"github.com/tendermint/tendermint/behaviour"
+	bc "github.com/tendermint/tendermint/blockchain"
+	"github.com/tendermint/tendermint/libs/log"
+	tmsync "github.com/tendermint/tendermint/libs/sync"
+	"github.com/tendermint/tendermint/p2p"
+	bcproto "github.com/tendermint/tendermint/proto/tendermint/blockchain"
+	"github.com/tendermint/tendermint/state"
+	"github.com/tendermint/tendermint/types"
+)
+
+const (
+	// chBufferSize is the buffer size of all event channels.
+	chBufferSize int = 1000
+)
+
+type blockStore interface {
+	LoadBlock(height int64) *types.Block
+	SaveBlock(*types.Block, *types.PartSet, *types.Commit)
+	Base() int64
+	Height() int64
+}
+
+// BlockchainReactor handles fast sync protocol.
+type BlockchainReactor struct {
+	p2p.BaseReactor
+
+	fastSync    bool // if true, enable fast sync on start
+	stateSynced bool // set to true when SwitchToFastSync is called by state sync
+	scheduler   *Routine
+	processor   *Routine
+	logger      log.Logger
+
+	mtx           tmsync.RWMutex
+	maxPeerHeight int64
+	syncHeight    int64
+	events        chan Event // non-nil during a fast sync
+
+	reporter behaviour.Reporter
+	io       iIO
+	store    blockStore
+}
+
+//nolint:unused,deadcode
+type blockVerifier interface {
+	VerifyCommit(chainID string, blockID types.BlockID, height int64, commit *types.Commit) error
+}
+
+type blockApplier interface {
+	ApplyBlock(state state.State, blockID types.BlockID, block *types.Block) (state.State, int64, error)
+}
+
+// XXX: unify naming in this package around tmState
+func newReactor(state state.State, store blockStore, reporter behaviour.Reporter,
+	blockApplier blockApplier, fastSync bool) *BlockchainReactor {
+	initHeight := state.LastBlockHeight + 1
+	if initHeight == 1 {
+		initHeight = state.InitialHeight
+	}
+	scheduler := newScheduler(initHeight, time.Now())
+	pContext := newProcessorContext(store, blockApplier, state)
+	// TODO: Fix naming to just newProcesssor
+	// newPcState requires a processorContext
+	processor := newPcState(pContext)
+
+	return &BlockchainReactor{
+		scheduler: newRoutine("scheduler", scheduler.handle, chBufferSize),
+		processor: newRoutine("processor", processor.handle, chBufferSize),
+		store:     store,
+		reporter:  reporter,
+		logger:    log.NewNopLogger(),
+		fastSync:  fastSync,
+	}
+}
+
+// NewBlockchainReactor creates a new reactor instance.
+func NewBlockchainReactor(
+	state state.State,
+	blockApplier blockApplier,
+	store blockStore,
+	fastSync bool) *BlockchainReactor {
+	reporter := behaviour.NewMockReporter()
+	return newReactor(state, store, reporter, blockApplier, fastSync)
+}
+
+// SetSwitch implements Reactor interface.
+func (r *BlockchainReactor) SetSwitch(sw *p2p.Switch) {
+	r.Switch = sw
+	if sw != nil {
+		r.io = newSwitchIo(sw)
+	} else {
+		r.io = nil
+	}
+}
+
+func (r *BlockchainReactor) setMaxPeerHeight(height int64) {
+	r.mtx.Lock()
+	defer r.mtx.Unlock()
+	if height > r.maxPeerHeight {
+		r.maxPeerHeight = height
+	}
+}
+
+func (r *BlockchainReactor) setSyncHeight(height int64) {
+	r.mtx.Lock()
+	defer r.mtx.Unlock()
+	r.syncHeight = height
+}
+
+// SyncHeight returns the height to which the BlockchainReactor has synced.
+func (r *BlockchainReactor) SyncHeight() int64 {
+	r.mtx.RLock()
+	defer r.mtx.RUnlock()
+	return r.syncHeight
+}
+
+// SetLogger sets the logger of the reactor.
+func (r *BlockchainReactor) SetLogger(logger log.Logger) {
+	r.logger = logger
+	r.scheduler.setLogger(logger)
+	r.processor.setLogger(logger)
+}
+
+// Start implements cmn.Service interface
+func (r *BlockchainReactor) Start() error {
+	r.reporter = behaviour.NewSwitchReporter(r.BaseReactor.Switch)
+	if r.fastSync {
+		err := r.startSync(nil)
+		if err != nil {
+			return fmt.Errorf("failed to start fast sync: %w", err)
+		}
+	}
+	return nil
+}
+
+// startSync begins a fast sync, signalled by r.events being non-nil. If state is non-nil,
+// the scheduler and processor is updated with this state on startup.
+func (r *BlockchainReactor) startSync(state *state.State) error {
+	r.mtx.Lock()
+	defer r.mtx.Unlock()
+	if r.events != nil {
+		return errors.New("fast sync already in progress")
+	}
+	r.events = make(chan Event, chBufferSize)
+	go r.scheduler.start()
+	go r.processor.start()
+	if state != nil {
+		<-r.scheduler.ready()
+		<-r.processor.ready()
+		r.scheduler.send(bcResetState{state: *state})
+		r.processor.send(bcResetState{state: *state})
+	}
+	go r.demux(r.events)
+	return nil
+}
+
+// endSync ends a fast sync
+func (r *BlockchainReactor) endSync() {
+	r.mtx.Lock()
+	defer r.mtx.Unlock()
+	if r.events != nil {
+		close(r.events)
+	}
+	r.events = nil
+	r.scheduler.stop()
+	r.processor.stop()
+}
+
+// SwitchToFastSync is called by the state sync reactor when switching to fast sync.
+func (r *BlockchainReactor) SwitchToFastSync(state state.State) error {
+	r.stateSynced = true
+	state = state.Copy()
+	return r.startSync(&state)
+}
+
+// reactor generated ticker events:
+// ticker for cleaning peers
+type rTryPrunePeer struct {
+	priorityHigh
+	time time.Time
+}
+
+func (e rTryPrunePeer) String() string {
+	return fmt.Sprintf("rTryPrunePeer{%v}", e.time)
+}
+
+// ticker event for scheduling block requests
+type rTrySchedule struct {
+	priorityHigh
+	time time.Time
+}
+
+func (e rTrySchedule) String() string {
+	return fmt.Sprintf("rTrySchedule{%v}", e.time)
+}
+
+// ticker for block processing
+type rProcessBlock struct {
+	priorityNormal
+}
+
+func (e rProcessBlock) String() string {
+	return "rProcessBlock"
+}
+
+// reactor generated events based on blockchain related messages from peers:
+// blockResponse message received from a peer
+type bcBlockResponse struct {
+	priorityNormal
+	time   time.Time
+	peerID p2p.ID
+	size   int
+	block  *types.Block
+}
+
+func (resp bcBlockResponse) String() string {
+	return fmt.Sprintf("bcBlockResponse{%d#%X (size: %d bytes) from %v at %v}",
+		resp.block.Height, resp.block.Hash(), resp.size, resp.peerID, resp.time)
+}
+
+// blockNoResponse message received from a peer
+type bcNoBlockResponse struct {
+	priorityNormal
+	time   time.Time
+	peerID p2p.ID
+	height int64
+}
+
+func (resp bcNoBlockResponse) String() string {
+	return fmt.Sprintf("bcNoBlockResponse{%v has no block at height %d at %v}",
+		resp.peerID, resp.height, resp.time)
+}
+
+// statusResponse message received from a peer
+type bcStatusResponse struct {
+	priorityNormal
+	time   time.Time
+	peerID p2p.ID
+	base   int64
+	height int64
+}
+
+func (resp bcStatusResponse) String() string {
+	return fmt.Sprintf("bcStatusResponse{%v is at height %d (base: %d) at %v}",
+		resp.peerID, resp.height, resp.base, resp.time)
+}
+
+// new peer is connected
+type bcAddNewPeer struct {
+	priorityNormal
+	peerID p2p.ID
+}
+
+func (resp bcAddNewPeer) String() string {
+	return fmt.Sprintf("bcAddNewPeer{%v}", resp.peerID)
+}
+
+// existing peer is removed
+type bcRemovePeer struct {
+	priorityHigh
+	peerID p2p.ID
+	reason interface{}
+}
+
+func (resp bcRemovePeer) String() string {
+	return fmt.Sprintf("bcRemovePeer{%v due to %v}", resp.peerID, resp.reason)
+}
+
+// resets the scheduler and processor state, e.g. following a switch from state syncing
+type bcResetState struct {
+	priorityHigh
+	state state.State
+}
+
+func (e bcResetState) String() string {
+	return fmt.Sprintf("bcResetState{%v}", e.state)
+}
+
+// Takes the channel as a parameter to avoid race conditions on r.events.
+func (r *BlockchainReactor) demux(events <-chan Event) {
+	var lastRate = 0.0
+	var lastHundred = time.Now()
+
+	var (
+		processBlockFreq = 20 * time.Millisecond
+		doProcessBlockCh = make(chan struct{}, 1)
+		doProcessBlockTk = time.NewTicker(processBlockFreq)
+	)
+	defer doProcessBlockTk.Stop()
+
+	var (
+		prunePeerFreq = 1 * time.Second
+		doPrunePeerCh = make(chan struct{}, 1)
+		doPrunePeerTk = time.NewTicker(prunePeerFreq)
+	)
+	defer doPrunePeerTk.Stop()
+
+	var (
+		scheduleFreq = 20 * time.Millisecond
+		doScheduleCh = make(chan struct{}, 1)
+		doScheduleTk = time.NewTicker(scheduleFreq)
+	)
+	defer doScheduleTk.Stop()
+
+	var (
+		statusFreq = 10 * time.Second
+		doStatusCh = make(chan struct{}, 1)
+		doStatusTk = time.NewTicker(statusFreq)
+	)
+	defer doStatusTk.Stop()
+	doStatusCh <- struct{}{} // immediately broadcast to get status of existing peers
+
+	// XXX: Extract timers to make testing atemporal
+	for {
+		select {
+		// Pacers: send at most per frequency but don't saturate
+		case <-doProcessBlockTk.C:
+			select {
+			case doProcessBlockCh <- struct{}{}:
+			default:
+			}
+		case <-doPrunePeerTk.C:
+			select {
+			case doPrunePeerCh <- struct{}{}:
+			default:
+			}
+		case <-doScheduleTk.C:
+			select {
+			case doScheduleCh <- struct{}{}:
+			default:
+			}
+		case <-doStatusTk.C:
+			select {
+			case doStatusCh <- struct{}{}:
+			default:
+			}
+
+		// Tickers: perform tasks periodically
+		case <-doScheduleCh:
+			r.scheduler.send(rTrySchedule{time: time.Now()})
+		case <-doPrunePeerCh:
+			r.scheduler.send(rTryPrunePeer{time: time.Now()})
+		case <-doProcessBlockCh:
+			r.processor.send(rProcessBlock{})
+		case <-doStatusCh:
+			r.io.broadcastStatusRequest()
+
+		// Events from peers. Closing the channel signals event loop termination.
+		case event, ok := <-events:
+			if !ok {
+				r.logger.Info("Stopping event processing")
+				return
+			}
+			switch event := event.(type) {
+			case bcStatusResponse:
+				r.setMaxPeerHeight(event.height)
+				r.scheduler.send(event)
+			case bcAddNewPeer, bcRemovePeer, bcBlockResponse, bcNoBlockResponse:
+				r.scheduler.send(event)
+			default:
+				r.logger.Error("Received unexpected event", "event", fmt.Sprintf("%T", event))
+			}
+
+		// Incremental events from scheduler
+		case event := <-r.scheduler.next():
+			switch event := event.(type) {
+			case scBlockReceived:
+				r.processor.send(event)
+			case scPeerError:
+				r.processor.send(event)
+				if err := r.reporter.Report(behaviour.BadMessage(event.peerID, "scPeerError")); err != nil {
+					r.logger.Error("Error reporting peer", "err", err)
+				}
+			case scBlockRequest:
+				if err := r.io.sendBlockRequest(event.peerID, event.height); err != nil {
+					r.logger.Error("Error sending block request", "err", err)
+				}
+			case scFinishedEv:
+				r.processor.send(event)
+				r.scheduler.stop()
+			case scSchedulerFail:
+				r.logger.Error("Scheduler failure", "err", event.reason.Error())
+			case scPeersPruned:
+				// Remove peers from the processor.
+				for _, peerID := range event.peers {
+					r.processor.send(scPeerError{peerID: peerID, reason: errors.New("peer was pruned")})
+				}
+				r.logger.Debug("Pruned peers", "count", len(event.peers))
+			case noOpEvent:
+			default:
+				r.logger.Error("Received unexpected scheduler event", "event", fmt.Sprintf("%T", event))
+			}
+
+		// Incremental events from processor
+		case event := <-r.processor.next():
+			switch event := event.(type) {
+			case pcBlockProcessed:
+				r.setSyncHeight(event.height)
+				if r.syncHeight%100 == 0 {
+					lastRate = 0.9*lastRate + 0.1*(100/time.Since(lastHundred).Seconds())
+					r.logger.Info("Fast Sync Rate", "height", r.syncHeight,
+						"max_peer_height", r.maxPeerHeight, "blocks/s", lastRate)
+					lastHundred = time.Now()
+				}
+				r.scheduler.send(event)
+			case pcBlockVerificationFailure:
+				r.scheduler.send(event)
+			case pcFinished:
+				r.logger.Info("Fast sync complete, switching to consensus")
+				if !r.io.trySwitchToConsensus(event.tmState, event.blocksSynced > 0 || r.stateSynced) {
+					r.logger.Error("Failed to switch to consensus reactor")
+				}
+				r.endSync()
+				return
+			case noOpEvent:
+			default:
+				r.logger.Error("Received unexpected processor event", "event", fmt.Sprintf("%T", event))
+			}
+
+		// Terminal event from scheduler
+		case err := <-r.scheduler.final():
+			switch err {
+			case nil:
+				r.logger.Info("Scheduler stopped")
+			default:
+				r.logger.Error("Scheduler aborted with error", "err", err)
+			}
+
+		// Terminal event from processor
+		case err := <-r.processor.final():
+			switch err {
+			case nil:
+				r.logger.Info("Processor stopped")
+			default:
+				r.logger.Error("Processor aborted with error", "err", err)
+			}
+		}
+	}
+}
+
+// Stop implements cmn.Service interface.
+func (r *BlockchainReactor) Stop() error {
+	r.logger.Info("reactor stopping")
+	r.endSync()
+	r.logger.Info("reactor stopped")
+	return nil
+}
+
+// Receive implements Reactor by handling different message types.
+func (r *BlockchainReactor) ReceiveEnvelope(e p2p.Envelope) {
+	if err := bc.ValidateMsg(e.Message); err != nil {
+		r.logger.Error("peer sent us invalid msg", "peer", e.Src, "msg", e.Message, "err", err)
+		_ = r.reporter.Report(behaviour.BadMessage(e.Src.ID(), err.Error()))
+		return
+	}
+
+	r.logger.Debug("Receive", "src", e.Src.ID(), "chID", e.ChannelID, "msg", e.Message)
+
+	switch msg := e.Message.(type) {
+	case *bcproto.StatusRequest:
+		if err := r.io.sendStatusResponse(r.store.Base(), r.store.Height(), e.Src.ID()); err != nil {
+			r.logger.Error("Could not send status message to peer", "src", e.Src)
+		}
+
+	case *bcproto.BlockRequest:
+		block := r.store.LoadBlock(msg.Height)
+		if block != nil {
+			if err := r.io.sendBlockToPeer(block, e.Src.ID()); err != nil {
+				r.logger.Error("Could not send block message to peer: ", err)
+			}
+		} else {
+			r.logger.Info("peer asking for a block we don't have", "src", e.Src, "height", msg.Height)
+			peerID := e.Src.ID()
+			if err := r.io.sendBlockNotFound(msg.Height, peerID); err != nil {
+				r.logger.Error("Couldn't send block not found: ", err)
+			}
+		}
+
+	case *bcproto.StatusResponse:
+		r.mtx.RLock()
+		if r.events != nil {
+			r.events <- bcStatusResponse{peerID: e.Src.ID(), base: msg.Base, height: msg.Height}
+		}
+		r.mtx.RUnlock()
+
+	case *bcproto.BlockResponse:
+		bi, err := types.BlockFromProto(msg.Block)
+		if err != nil {
+			r.logger.Error("error transitioning block from protobuf", "err", err)
+			return
+		}
+		r.mtx.RLock()
+		if r.events != nil {
+			r.events <- bcBlockResponse{
+				peerID: e.Src.ID(),
+				block:  bi,
+				time:   time.Now(),
+				size:   msg.Size(),
+			}
+		}
+		r.mtx.RUnlock()
+
+	case *bcproto.NoBlockResponse:
+		r.mtx.RLock()
+		if r.events != nil {
+			r.events <- bcNoBlockResponse{peerID: e.Src.ID(), height: msg.Height, time: time.Now()}
+		}
+		r.mtx.RUnlock()
+	}
+}
+
+func (r *BlockchainReactor) Receive(chID byte, peer p2p.Peer, msgBytes []byte) {
+	msg := &bcproto.Message{}
+	err := proto.Unmarshal(msgBytes, msg)
+	if err != nil {
+		panic(err)
+	}
+	uw, err := msg.Unwrap()
+	if err != nil {
+		panic(err)
+	}
+	r.ReceiveEnvelope(p2p.Envelope{
+		ChannelID: chID,
+		Src:       peer,
+		Message:   uw,
+	})
+}
+
+// AddPeer implements Reactor interface
+func (r *BlockchainReactor) AddPeer(peer p2p.Peer) {
+	err := r.io.sendStatusResponse(r.store.Base(), r.store.Height(), peer.ID())
+	if err != nil {
+		r.logger.Error("Could not send status message to peer new", "src", peer.ID, "height", r.SyncHeight())
+	}
+	r.mtx.RLock()
+	defer r.mtx.RUnlock()
+	if r.events != nil {
+		r.events <- bcAddNewPeer{peerID: peer.ID()}
+	}
+}
+
+// RemovePeer implements Reactor interface.
+func (r *BlockchainReactor) RemovePeer(peer p2p.Peer, reason interface{}) {
+	r.mtx.RLock()
+	defer r.mtx.RUnlock()
+	if r.events != nil {
+		r.events <- bcRemovePeer{
+			peerID: peer.ID(),
+			reason: reason,
+		}
+	}
+}
+
+// GetChannels implements Reactor
+func (r *BlockchainReactor) GetChannels() []*p2p.ChannelDescriptor {
+	return []*p2p.ChannelDescriptor{
+		{
+			ID:                  BlockchainChannel,
+			Priority:            5,
+			SendQueueCapacity:   2000,
+			RecvBufferCapacity:  50 * 4096,
+			RecvMessageCapacity: bc.MaxMsgSize,
+			MessageType:         &bcproto.Message{},
+		},
+	}
+}

blockchain/v2/reactor_test.go

@@ -0,0 +1,576 @@
+package v2
+
+import (
+	"fmt"
+	"net"
+	"os"
+	"sort"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/gogo/protobuf/proto"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	dbm "github.com/tendermint/tm-db"
+
+	abci "github.com/tendermint/tendermint/abci/types"
+	"github.com/tendermint/tendermint/behaviour"
+	cfg "github.com/tendermint/tendermint/config"
+	"github.com/tendermint/tendermint/libs/log"
+	"github.com/tendermint/tendermint/libs/service"
+	"github.com/tendermint/tendermint/mempool/mock"
+	"github.com/tendermint/tendermint/p2p"
+	"github.com/tendermint/tendermint/p2p/conn"
+	bcproto "github.com/tendermint/tendermint/proto/tendermint/blockchain"
+	"github.com/tendermint/tendermint/proxy"
+	sm "github.com/tendermint/tendermint/state"
+	"github.com/tendermint/tendermint/store"
+	"github.com/tendermint/tendermint/types"
+	tmtime "github.com/tendermint/tendermint/types/time"
+)
+
+type mockPeer struct {
+	service.Service
+	id p2p.ID
+}
+
+func (mp mockPeer) FlushStop()           {}
+func (mp mockPeer) ID() p2p.ID           { return mp.id }
+func (mp mockPeer) RemoteIP() net.IP     { return net.IP{} }
+func (mp mockPeer) RemoteAddr() net.Addr { return &net.TCPAddr{IP: mp.RemoteIP(), Port: 8800} }
+
+func (mp mockPeer) IsOutbound() bool   { return true }
+func (mp mockPeer) IsPersistent() bool { return true }
+func (mp mockPeer) CloseConn() error   { return nil }
+
+func (mp mockPeer) NodeInfo() p2p.NodeInfo {
+	return p2p.DefaultNodeInfo{
+		DefaultNodeID: "",
+		ListenAddr:    "",
+	}
+}
+func (mp mockPeer) Status() conn.ConnectionStatus { return conn.ConnectionStatus{} }
+func (mp mockPeer) SocketAddr() *p2p.NetAddress   { return &p2p.NetAddress{} }
+
+func (mp mockPeer) SendEnvelope(e p2p.Envelope) bool    { return true }
+func (mp mockPeer) TrySendEnvelope(e p2p.Envelope) bool { return true }
+
+func (mp mockPeer) Send(byte, []byte) bool    { return true }
+func (mp mockPeer) TrySend(byte, []byte) bool { return true }
+
+func (mp mockPeer) Set(string, interface{}) {}
+func (mp mockPeer) Get(string) interface{}  { return struct{}{} }
+
+func (mp mockPeer) SetRemovalFailed()      {}
+func (mp mockPeer) GetRemovalFailed() bool { return false }
+
+type mockBlockApplier struct{}
+
+// XXX: Add whitelist/blacklist?
+func (mba *mockBlockApplier) ApplyBlock(
+	state sm.State, blockID types.BlockID, block *types.Block,
+) (sm.State, int64, error) {
+	state.LastBlockHeight++
+	return state, 0, nil
+}
+
+type mockSwitchIo struct {
+	mtx                 sync.Mutex
+	switchedToConsensus bool
+	numStatusResponse   int
+	numBlockResponse    int
+	numNoBlockResponse  int
+}
+
+func (sio *mockSwitchIo) sendBlockRequest(peerID p2p.ID, height int64) error {
+	return nil
+}
+
+func (sio *mockSwitchIo) sendStatusResponse(base, height int64, peerID p2p.ID) error {
+	sio.mtx.Lock()
+	defer sio.mtx.Unlock()
+	sio.numStatusResponse++
+	return nil
+}
+
+func (sio *mockSwitchIo) sendBlockToPeer(block *types.Block, peerID p2p.ID) error {
+	sio.mtx.Lock()
+	defer sio.mtx.Unlock()
+	sio.numBlockResponse++
+	return nil
+}
+
+func (sio *mockSwitchIo) sendBlockNotFound(height int64, peerID p2p.ID) error {
+	sio.mtx.Lock()
+	defer sio.mtx.Unlock()
+	sio.numNoBlockResponse++
+	return nil
+}
+
+func (sio *mockSwitchIo) trySwitchToConsensus(state sm.State, skipWAL bool) bool {
+	sio.mtx.Lock()
+	defer sio.mtx.Unlock()
+	sio.switchedToConsensus = true
+	return true
+}
+
+func (sio *mockSwitchIo) broadcastStatusRequest() {
+}
+
+type testReactorParams struct {
+	logger      log.Logger
+	genDoc      *types.GenesisDoc
+	privVals    []types.PrivValidator
+	startHeight int64
+	mockA       bool
+}
+
+func newTestReactor(p testReactorParams) *BlockchainReactor {
+	store, state, _ := newReactorStore(p.genDoc, p.privVals, p.startHeight)
+	reporter := behaviour.NewMockReporter()
+
+	var appl blockApplier
+
+	if p.mockA {
+		appl = &mockBlockApplier{}
+	} else {
+		app := &testApp{}
+		cc := proxy.NewLocalClientCreator(app)
+		proxyApp := proxy.NewAppConns(cc)
+		err := proxyApp.Start()
+		if err != nil {
+			panic(fmt.Errorf("error start app: %w", err))
+		}
+		db := dbm.NewMemDB()
+		stateStore := sm.NewStore(db, sm.StoreOptions{
+			DiscardABCIResponses: false,
+		})
+		appl = sm.NewBlockExecutor(stateStore, p.logger, proxyApp.Consensus(), mock.Mempool{}, sm.EmptyEvidencePool{})
+		if err = stateStore.Save(state); err != nil {
+			panic(err)
+		}
+	}
+
+	r := newReactor(state, store, reporter, appl, true)
+	logger := log.TestingLogger()
+	r.SetLogger(logger.With("module", "blockchain"))
+
+	return r
+}
+
+// This test is left here and not deleted to retain the termination cases for
+// future improvement in [#4482](https://github.com/tendermint/tendermint/issues/4482).
+// func TestReactorTerminationScenarios(t *testing.T) {
+
+// 	config := cfg.ResetTestRoot("blockchain_reactor_v2_test")
+// 	defer os.RemoveAll(config.RootDir)
+// 	genDoc, privVals := randGenesisDoc(config.ChainID(), 1, false, 30)
+// 	refStore, _, _ := newReactorStore(genDoc, privVals, 20)
+
+// 	params := testReactorParams{
+// 		logger:      log.TestingLogger(),
+// 		genDoc:      genDoc,
+// 		privVals:    privVals,
+// 		startHeight: 10,
+// 		bufferSize:  100,
+// 		mockA:       true,
+// 	}
+
+// 	type testEvent struct {
+// 		evType string
+// 		peer   string
+// 		height int64
+// 	}
+
+// 	tests := []struct {
+// 		name   string
+// 		params testReactorParams
+// 		msgs   []testEvent
+// 	}{
+// 		{
+// 			name:   "simple termination on max peer height - one peer",
+// 			params: params,
+// 			msgs: []testEvent{
+// 				{evType: "AddPeer", peer: "P1"},
+// 				{evType: "ReceiveS", peer: "P1", height: 13},
+// 				{evType: "BlockReq"},
+// 				{evType: "ReceiveB", peer: "P1", height: 11},
+// 				{evType: "BlockReq"},
+// 				{evType: "BlockReq"},
+// 				{evType: "ReceiveB", peer: "P1", height: 12},
+// 				{evType: "Process"},
+// 				{evType: "ReceiveB", peer: "P1", height: 13},
+// 				{evType: "Process"},
+// 			},
+// 		},
+// 		{
+// 			name:   "simple termination on max peer height - two peers",
+// 			params: params,
+// 			msgs: []testEvent{
+// 				{evType: "AddPeer", peer: "P1"},
+// 				{evType: "AddPeer", peer: "P2"},
+// 				{evType: "ReceiveS", peer: "P1", height: 13},
+// 				{evType: "ReceiveS", peer: "P2", height: 15},
+// 				{evType: "BlockReq"},
+// 				{evType: "BlockReq"},
+// 				{evType: "ReceiveB", peer: "P1", height: 11},
+// 				{evType: "ReceiveB", peer: "P2", height: 12},
+// 				{evType: "Process"},
+// 				{evType: "BlockReq"},
+// 				{evType: "BlockReq"},
+// 				{evType: "ReceiveB", peer: "P1", height: 13},
+// 				{evType: "Process"},
+// 				{evType: "ReceiveB", peer: "P2", height: 14},
+// 				{evType: "Process"},
+// 				{evType: "BlockReq"},
+// 				{evType: "ReceiveB", peer: "P2", height: 15},
+// 				{evType: "Process"},
+// 			},
+// 		},
+// 		{
+// 			name:   "termination on max peer height - two peers, noBlock error",
+// 			params: params,
+// 			msgs: []testEvent{
+// 				{evType: "AddPeer", peer: "P1"},
+// 				{evType: "AddPeer", peer: "P2"},
+// 				{evType: "ReceiveS", peer: "P1", height: 13},
+// 				{evType: "ReceiveS", peer: "P2", height: 15},
+// 				{evType: "BlockReq"},
+// 				{evType: "BlockReq"},
+// 				{evType: "ReceiveNB", peer: "P1", height: 11},
+// 				{evType: "BlockReq"},
+// 				{evType: "ReceiveB", peer: "P2", height: 12},
+// 				{evType: "ReceiveB", peer: "P2", height: 11},
+// 				{evType: "Process"},
+// 				{evType: "BlockReq"},
+// 				{evType: "BlockReq"},
+// 				{evType: "ReceiveB", peer: "P2", height: 13},
+// 				{evType: "Process"},
+// 				{evType: "ReceiveB", peer: "P2", height: 14},
+// 				{evType: "Process"},
+// 				{evType: "BlockReq"},
+// 				{evType: "ReceiveB", peer: "P2", height: 15},
+// 				{evType: "Process"},
+// 			},
+// 		},
+// 		{
+// 			name:   "termination on max peer height - two peers, remove one peer",
+// 			params: params,
+// 			msgs: []testEvent{
+// 				{evType: "AddPeer", peer: "P1"},
+// 				{evType: "AddPeer", peer: "P2"},
+// 				{evType: "ReceiveS", peer: "P1", height: 13},
+// 				{evType: "ReceiveS", peer: "P2", height: 15},
+// 				{evType: "BlockReq"},
+// 				{evType: "BlockReq"},
+// 				{evType: "RemovePeer", peer: "P1"},
+// 				{evType: "BlockReq"},
+// 				{evType: "ReceiveB", peer: "P2", height: 12},
+// 				{evType: "ReceiveB", peer: "P2", height: 11},
+// 				{evType: "Process"},
+// 				{evType: "BlockReq"},
+// 				{evType: "BlockReq"},
+// 				{evType: "ReceiveB", peer: "P2", height: 13},
+// 				{evType: "Process"},
+// 				{evType: "ReceiveB", peer: "P2", height: 14},
+// 				{evType: "Process"},
+// 				{evType: "BlockReq"},
+// 				{evType: "ReceiveB", peer: "P2", height: 15},
+// 				{evType: "Process"},
+// 			},
+// 		},
+// 	}
+
+// 	for _, tt := range tests {
+// 		tt := tt
+// 		t.Run(tt.name, func(t *testing.T) {
+// 			reactor := newTestReactor(params)
+// 			reactor.Start()
+// 			reactor.reporter = behaviour.NewMockReporter()
+// 			mockSwitch := &mockSwitchIo{switchedToConsensus: false}
+// 			reactor.io = mockSwitch
+// 			// time for go routines to start
+// 			time.Sleep(time.Millisecond)
+
+// 			for _, step := range tt.msgs {
+// 				switch step.evType {
+// 				case "AddPeer":
+// 					reactor.scheduler.send(bcAddNewPeer{peerID: p2p.ID(step.peer)})
+// 				case "RemovePeer":
+// 					reactor.scheduler.send(bcRemovePeer{peerID: p2p.ID(step.peer)})
+// 				case "ReceiveS":
+// 					reactor.scheduler.send(bcStatusResponse{
+// 						peerID: p2p.ID(step.peer),
+// 						height: step.height,
+// 						time:   time.Now(),
+// 					})
+// 				case "ReceiveB":
+// 					reactor.scheduler.send(bcBlockResponse{
+// 						peerID: p2p.ID(step.peer),
+// 						block:  refStore.LoadBlock(step.height),
+// 						size:   10,
+// 						time:   time.Now(),
+// 					})
+// 				case "ReceiveNB":
+// 					reactor.scheduler.send(bcNoBlockResponse{
+// 						peerID: p2p.ID(step.peer),
+// 						height: step.height,
+// 						time:   time.Now(),
+// 					})
+// 				case "BlockReq":
+// 					reactor.scheduler.send(rTrySchedule{time: time.Now()})
+// 				case "Process":
+// 					reactor.processor.send(rProcessBlock{})
+// 				}
+// 				// give time for messages to propagate between routines
+// 				time.Sleep(time.Millisecond)
+// 			}
+
+// 			// time for processor to finish and reactor to switch to consensus
+// 			time.Sleep(20 * time.Millisecond)
+// 			assert.True(t, mockSwitch.hasSwitchedToConsensus())
+// 			reactor.Stop()
+// 		})
+// 	}
+// }
+
+func TestReactorHelperMode(t *testing.T) {
+	channelID := byte(0x40)
+
+	config := cfg.ResetTestRoot("blockchain_reactor_v2_test")
+	defer os.RemoveAll(config.RootDir)
+	genDoc, privVals := randGenesisDoc(config.ChainID(), 1, false, 30)
+
+	params := testReactorParams{
+		logger:      log.TestingLogger(),
+		genDoc:      genDoc,
+		privVals:    privVals,
+		startHeight: 20,
+		mockA:       true,
+	}
+
+	type testEvent struct {
+		peer  string
+		event proto.Message
+	}
+
+	tests := []struct {
+		name   string
+		params testReactorParams
+		msgs   []testEvent
+	}{
+		{
+			name:   "status request",
+			params: params,
+			msgs: []testEvent{
+				{"P1", &bcproto.StatusRequest{}},
+				{"P1", &bcproto.BlockRequest{Height: 13}},
+				{"P1", &bcproto.BlockRequest{Height: 20}},
+				{"P1", &bcproto.BlockRequest{Height: 22}},
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		tt := tt
+		t.Run(tt.name, func(t *testing.T) {
+			reactor := newTestReactor(params)
+			mockSwitch := &mockSwitchIo{switchedToConsensus: false}
+			reactor.io = mockSwitch
+			err := reactor.Start()
+			require.NoError(t, err)
+
+			for i := 0; i < len(tt.msgs); i++ {
+				step := tt.msgs[i]
+				switch ev := step.event.(type) {
+				case *bcproto.StatusRequest:
+					old := mockSwitch.numStatusResponse
+					reactor.ReceiveEnvelope(p2p.Envelope{
+						ChannelID: channelID,
+						Src:       mockPeer{id: p2p.ID(step.peer)},
+						Message:   ev})
+					assert.Equal(t, old+1, mockSwitch.numStatusResponse)
+				case *bcproto.BlockRequest:
+					if ev.Height > params.startHeight {
+						old := mockSwitch.numNoBlockResponse
+						reactor.ReceiveEnvelope(p2p.Envelope{
+							ChannelID: channelID,
+							Src:       mockPeer{id: p2p.ID(step.peer)},
+							Message:   ev})
+						assert.Equal(t, old+1, mockSwitch.numNoBlockResponse)
+					} else {
+						old := mockSwitch.numBlockResponse
+						reactor.ReceiveEnvelope(p2p.Envelope{
+							ChannelID: channelID,
+							Src:       mockPeer{id: p2p.ID(step.peer)},
+							Message:   ev})
+						assert.Equal(t, old+1, mockSwitch.numBlockResponse)
+					}
+				}
+			}
+			err = reactor.Stop()
+			require.NoError(t, err)
+		})
+	}
+}
+
+func TestLegacyReactorReceiveBasic(t *testing.T) {
+	config := cfg.ResetTestRoot("blockchain_reactor_v2_test")
+	defer os.RemoveAll(config.RootDir)
+	genDoc, privVals := randGenesisDoc(config.ChainID(), 1, false, 30)
+	params := testReactorParams{
+		logger:      log.TestingLogger(),
+		genDoc:      genDoc,
+		privVals:    privVals,
+		startHeight: 20,
+		mockA:       true,
+	}
+	reactor := newTestReactor(params)
+	mockSwitch := &mockSwitchIo{switchedToConsensus: false}
+	reactor.io = mockSwitch
+	peer := p2p.CreateRandomPeer(false)
+
+	reactor.InitPeer(peer)
+	reactor.AddPeer(peer)
+	m := &bcproto.StatusRequest{}
+	wm := m.Wrap()
+	msg, err := proto.Marshal(wm)
+	assert.NoError(t, err)
+
+	assert.NotPanics(t, func() {
+		reactor.Receive(BlockchainChannel, peer, msg)
+	})
+}
+
+func TestReactorSetSwitchNil(t *testing.T) {
+	config := cfg.ResetTestRoot("blockchain_reactor_v2_test")
+	defer os.RemoveAll(config.RootDir)
+	genDoc, privVals := randGenesisDoc(config.ChainID(), 1, false, 30)
+
+	reactor := newTestReactor(testReactorParams{
+		logger:   log.TestingLogger(),
+		genDoc:   genDoc,
+		privVals: privVals,
+	})
+	reactor.SetSwitch(nil)
+
+	assert.Nil(t, reactor.Switch)
+	assert.Nil(t, reactor.io)
+}
+
+//----------------------------------------------
+// utility funcs
+
+func makeTxs(height int64) (txs []types.Tx) {
+	for i := 0; i < 10; i++ {
+		txs = append(txs, types.Tx([]byte{byte(height), byte(i)}))
+	}
+	return txs
+}
+
+func makeBlock(height int64, state sm.State, lastCommit *types.Commit) *types.Block {
+	block, _ := state.MakeBlock(height, makeTxs(height), lastCommit, nil, state.Validators.GetProposer().Address)
+	return block
+}
+
+type testApp struct {
+	abci.BaseApplication
+}
+
+func randGenesisDoc(chainID string, numValidators int, randPower bool, minPower int64) (
+	*types.GenesisDoc, []types.PrivValidator,
+) {
+	validators := make([]types.GenesisValidator, numValidators)
+	privValidators := make([]types.PrivValidator, numValidators)
+	for i := 0; i < numValidators; i++ {
+		val, privVal := types.RandValidator(randPower, minPower)
+		validators[i] = types.GenesisValidator{
+			PubKey: val.PubKey,
+			Power:  val.VotingPower,
+		}
+		privValidators[i] = privVal
+	}
+	sort.Sort(types.PrivValidatorsByAddress(privValidators))
+
+	return &types.GenesisDoc{
+		GenesisTime: tmtime.Now(),
+		ChainID:     chainID,
+		Validators:  validators,
+	}, privValidators
+}
+
+// Why are we importing the entire blockExecutor dependency graph here
+// when we have the facilities to
+func newReactorStore(
+	genDoc *types.GenesisDoc,
+	privVals []types.PrivValidator,
+	maxBlockHeight int64,
+) (*store.BlockStore, sm.State, *sm.BlockExecutor) {
+	if len(privVals) != 1 {
+		panic("only support one validator")
+	}
+	app := &testApp{}
+	cc := proxy.NewLocalClientCreator(app)
+	proxyApp := proxy.NewAppConns(cc)
+	err := proxyApp.Start()
+	if err != nil {
+		panic(fmt.Errorf("error start app: %w", err))
+	}
+
+	stateDB := dbm.NewMemDB()
+	blockStore := store.NewBlockStore(dbm.NewMemDB())
+	stateStore := sm.NewStore(stateDB, sm.StoreOptions{
+		DiscardABCIResponses: false,
+	})
+	state, err := stateStore.LoadFromDBOrGenesisDoc(genDoc)
+	if err != nil {
+		panic(fmt.Errorf("error constructing state from genesis file: %w", err))
+	}
+
+	db := dbm.NewMemDB()
+	stateStore = sm.NewStore(db, sm.StoreOptions{
+		DiscardABCIResponses: false,
+	},
+	)
+	blockExec := sm.NewBlockExecutor(stateStore, log.TestingLogger(), proxyApp.Consensus(),
+		mock.Mempool{}, sm.EmptyEvidencePool{})
+	if err = stateStore.Save(state); err != nil {
+		panic(err)
+	}
+
+	// add blocks in
+	for blockHeight := int64(1); blockHeight <= maxBlockHeight; blockHeight++ {
+		lastCommit := types.NewCommit(blockHeight-1, 0, types.BlockID{}, nil)
+		if blockHeight > 1 {
+			lastBlockMeta := blockStore.LoadBlockMeta(blockHeight - 1)
+			lastBlock := blockStore.LoadBlock(blockHeight - 1)
+			vote, err := types.MakeVote(
+				lastBlock.Header.Height,
+				lastBlockMeta.BlockID,
+				state.Validators,
+				privVals[0],
+				lastBlock.Header.ChainID,
+				time.Now(),
+			)
+			if err != nil {
+				panic(err)
+			}
+			lastCommit = types.NewCommit(vote.Height, vote.Round,
+				lastBlockMeta.BlockID, []types.CommitSig{vote.CommitSig()})
+		}
+
+		thisBlock := makeBlock(blockHeight, state, lastCommit)
+
+		thisParts := thisBlock.MakePartSet(types.BlockPartSizeBytes)
+		blockID := types.BlockID{Hash: thisBlock.Hash(), PartSetHeader: thisParts.Header()}
+
+		state, _, err = blockExec.ApplyBlock(state, blockID, thisBlock)
+		if err != nil {
+			panic(fmt.Errorf("error apply block: %w", err))
+		}
+
+		blockStore.SaveBlock(thisBlock, thisParts, lastCommit)
+	}
+	return blockStore, state, blockExec
+}

blockchain/v2/routine.go

@@ -0,0 +1,161 @@
+package v2
+
+import (
+	"fmt"
+	"strings"
+	"sync/atomic"
+
+	"github.com/Workiva/go-datastructures/queue"
+
+	"github.com/tendermint/tendermint/libs/log"
+)
+
+type handleFunc = func(event Event) (Event, error)
+
+const historySize = 25
+
+// Routine is a structure that models a finite state machine as serialized
+// stream of events processed by a handle function. This Routine structure
+// handles the concurrency and messaging guarantees. Events are sent via
+// `send` are handled by the `handle` function to produce an iterator
+// `next()`. Calling `stop()` on a routine will conclude processing of all
+// sent events and produce `final()` event representing the terminal state.
+type Routine struct {
+	name    string
+	handle  handleFunc
+	queue   *queue.PriorityQueue
+	history []Event
+	out     chan Event
+	fin     chan error
+	rdy     chan struct{}
+	running *uint32
+	logger  log.Logger
+	metrics *Metrics
+}
+
+func newRoutine(name string, handleFunc handleFunc, bufferSize int) *Routine {
+	return &Routine{
+		name:    name,
+		handle:  handleFunc,
+		queue:   queue.NewPriorityQueue(bufferSize, true),
+		history: make([]Event, 0, historySize),
+		out:     make(chan Event, bufferSize),
+		rdy:     make(chan struct{}, 1),
+		fin:     make(chan error, 1),
+		running: new(uint32),
+		logger:  log.NewNopLogger(),
+		metrics: NopMetrics(),
+	}
+}
+
+func (rt *Routine) setLogger(logger log.Logger) {
+	rt.logger = logger
+}
+
+func (rt *Routine) start() {
+	rt.logger.Info("routine start", "msg", log.NewLazySprintf("%s: run", rt.name))
+	running := atomic.CompareAndSwapUint32(rt.running, uint32(0), uint32(1))
+	if !running {
+		panic(fmt.Sprintf("%s is already running", rt.name))
+	}
+	close(rt.rdy)
+	defer func() {
+		if r := recover(); r != nil {
+			var (
+				b strings.Builder
+				j int
+			)
+			for i := len(rt.history) - 1; i >= 0; i-- {
+				fmt.Fprintf(&b, "%d: %+v\n", j, rt.history[i])
+				j++
+			}
+			panic(fmt.Sprintf("%v\nlast events:\n%v", r, b.String()))
+		}
+		stopped := atomic.CompareAndSwapUint32(rt.running, uint32(1), uint32(0))
+		if !stopped {
+			panic(fmt.Sprintf("%s is failed to stop", rt.name))
+		}
+	}()
+
+	for {
+		events, err := rt.queue.Get(1)
+		if err == queue.ErrDisposed {
+			rt.terminate(nil)
+			return
+		} else if err != nil {
+			rt.terminate(err)
+			return
+		}
+		oEvent, err := rt.handle(events[0].(Event))
+		rt.metrics.EventsHandled.With("routine", rt.name).Add(1)
+		if err != nil {
+			rt.terminate(err)
+			return
+		}
+		rt.metrics.EventsOut.With("routine", rt.name).Add(1)
+		rt.logger.Debug("routine start", "msg", log.NewLazySprintf("%s: produced %T %+v", rt.name, oEvent, oEvent))
+
+		// Skip rTrySchedule and rProcessBlock events as they clutter the history
+		// due to their frequency.
+		switch events[0].(type) {
+		case rTrySchedule:
+		case rProcessBlock:
+		default:
+			rt.history = append(rt.history, events[0].(Event))
+			if len(rt.history) > historySize {
+				rt.history = rt.history[1:]
+			}
+		}
+
+		rt.out <- oEvent
+	}
+}
+
+// XXX: look into returning OpError in the net package
+func (rt *Routine) send(event Event) bool {
+	rt.logger.Debug("routine send", "msg", log.NewLazySprintf("%s: received %T %+v", rt.name, event, event))
+	if !rt.isRunning() {
+		return false
+	}
+	err := rt.queue.Put(event)
+	if err != nil {
+		rt.metrics.EventsShed.With("routine", rt.name).Add(1)
+		rt.logger.Error(fmt.Sprintf("%s: send failed, queue was full/stopped", rt.name))
+		return false
+	}
+
+	rt.metrics.EventsSent.With("routine", rt.name).Add(1)
+	return true
+}
+
+func (rt *Routine) isRunning() bool {
+	return atomic.LoadUint32(rt.running) == 1
+}
+
+func (rt *Routine) next() chan Event {
+	return rt.out
+}
+
+func (rt *Routine) ready() chan struct{} {
+	return rt.rdy
+}
+
+func (rt *Routine) stop() {
+	if !rt.isRunning() { // XXX: this should check rt.queue.Disposed()
+		return
+	}
+
+	rt.logger.Info("routine stop", "msg", log.NewLazySprintf("%s: stop", rt.name))
+	rt.queue.Dispose() // this should block until all queue items are free?
+}
+
+func (rt *Routine) final() chan error {
+	return rt.fin
+}
+
+// XXX: Maybe get rid of this
+func (rt *Routine) terminate(reason error) {
+	// We don't close the rt.out channel here, to avoid spinning on the closed channel
+	// in the event loop.
+	rt.fin <- reason
+}

blockchain/v2/routine_test.go

@@ -0,0 +1,163 @@
+package v2
+
+import (
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+type eventA struct {
+	priorityNormal
+}
+
+var errDone = fmt.Errorf("done")
+
+func simpleHandler(event Event) (Event, error) {
+	if _, ok := event.(eventA); ok {
+		return noOp, errDone
+	}
+	return noOp, nil
+}
+
+func TestRoutineFinal(t *testing.T) {
+	var (
+		bufferSize = 10
+		routine    = newRoutine("simpleRoutine", simpleHandler, bufferSize)
+	)
+
+	assert.False(t, routine.isRunning(),
+		"expected an initialized routine to not be running")
+	go routine.start()
+	<-routine.ready()
+	assert.True(t, routine.isRunning(),
+		"expected an started routine")
+
+	assert.True(t, routine.send(eventA{}),
+		"expected sending to a ready routine to succeed")
+
+	assert.Equal(t, errDone, <-routine.final(),
+		"expected the final event to be done")
+
+	assert.False(t, routine.isRunning(),
+		"expected an completed routine to no longer be running")
+}
+
+func TestRoutineStop(t *testing.T) {
+	var (
+		bufferSize = 10
+		routine    = newRoutine("simpleRoutine", simpleHandler, bufferSize)
+	)
+
+	assert.False(t, routine.send(eventA{}),
+		"expected sending to an unstarted routine to fail")
+
+	go routine.start()
+	<-routine.ready()
+
+	assert.True(t, routine.send(eventA{}),
+		"expected sending to a running routine to succeed")
+
+	routine.stop()
+
+	assert.False(t, routine.send(eventA{}),
+		"expected sending to a stopped routine to fail")
+}
+
+type finalCount struct {
+	count int
+}
+
+func (f finalCount) Error() string {
+	return "end"
+}
+
+func genStatefulHandler(maxCount int) handleFunc {
+	counter := 0
+	return func(event Event) (Event, error) {
+		if _, ok := event.(eventA); ok {
+			counter++
+			if counter >= maxCount {
+				return noOp, finalCount{counter}
+			}
+
+			return eventA{}, nil
+		}
+		return noOp, nil
+	}
+}
+
+func feedback(r *Routine) {
+	for event := range r.next() {
+		r.send(event)
+	}
+}
+
+func TestStatefulRoutine(t *testing.T) {
+	var (
+		count      = 10
+		handler    = genStatefulHandler(count)
+		bufferSize = 20
+		routine    = newRoutine("statefulRoutine", handler, bufferSize)
+	)
+
+	go routine.start()
+	go feedback(routine)
+	<-routine.ready()
+
+	assert.True(t, routine.send(eventA{}),
+		"expected sending to a started routine to succeed")
+
+	final := <-routine.final()
+	if fnl, ok := final.(finalCount); ok {
+		assert.Equal(t, count, fnl.count,
+			"expected the routine to count to 10")
+	} else {
+		t.Fail()
+	}
+}
+
+type lowPriorityEvent struct {
+	priorityLow
+}
+
+type highPriorityEvent struct {
+	priorityHigh
+}
+
+func handleWithPriority(event Event) (Event, error) {
+	switch event.(type) {
+	case lowPriorityEvent:
+		return noOp, nil
+	case highPriorityEvent:
+		return noOp, errDone
+	}
+	return noOp, nil
+}
+
+func TestPriority(t *testing.T) {
+	var (
+		bufferSize = 20
+		routine    = newRoutine("priorityRoutine", handleWithPriority, bufferSize)
+	)
+
+	go routine.start()
+	<-routine.ready()
+	go func() {
+		for {
+			routine.send(lowPriorityEvent{})
+			time.Sleep(1 * time.Millisecond)
+		}
+	}()
+	time.Sleep(10 * time.Millisecond)
+
+	assert.True(t, routine.isRunning(),
+		"expected an started routine")
+	assert.True(t, routine.send(highPriorityEvent{}),
+		"expected send to succeed even when saturated")
+
+	assert.Equal(t, errDone, <-routine.final())
+	assert.False(t, routine.isRunning(),
+		"expected an started routine")
+}

blockchain/v2/scheduler.go

@@ -0,0 +1,712 @@
+package v2
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"math"
+	"sort"
+	"time"
+
+	"github.com/tendermint/tendermint/p2p"
+	"github.com/tendermint/tendermint/types"
+)
+
+// Events generated by the scheduler:
+// all blocks have been processed
+type scFinishedEv struct {
+	priorityNormal
+	reason string
+}
+
+func (e scFinishedEv) String() string {
+	return fmt.Sprintf("scFinishedEv{%v}", e.reason)
+}
+
+// send a blockRequest message
+type scBlockRequest struct {
+	priorityNormal
+	peerID p2p.ID
+	height int64
+}
+
+func (e scBlockRequest) String() string {
+	return fmt.Sprintf("scBlockRequest{%d from %v}", e.height, e.peerID)
+}
+
+// a block has been received and validated by the scheduler
+type scBlockReceived struct {
+	priorityNormal
+	peerID p2p.ID
+	block  *types.Block
+}
+
+func (e scBlockReceived) String() string {
+	return fmt.Sprintf("scBlockReceived{%d#%X from %v}", e.block.Height, e.block.Hash(), e.peerID)
+}
+
+// scheduler detected a peer error
+type scPeerError struct {
+	priorityHigh
+	peerID p2p.ID
+	reason error
+}
+
+func (e scPeerError) String() string {
+	return fmt.Sprintf("scPeerError{%v errored with %v}", e.peerID, e.reason)
+}
+
+// scheduler removed a set of peers (timed out or slow peer)
+type scPeersPruned struct {
+	priorityHigh
+	peers []p2p.ID
+}
+
+func (e scPeersPruned) String() string {
+	return fmt.Sprintf("scPeersPruned{%v}", e.peers)
+}
+
+// XXX: make this fatal?
+// scheduler encountered a fatal error
+type scSchedulerFail struct {
+	priorityHigh
+	reason error
+}
+
+func (e scSchedulerFail) String() string {
+	return fmt.Sprintf("scSchedulerFail{%v}", e.reason)
+}
+
+type blockState int
+
+const (
+	blockStateUnknown   blockState = iota + 1 // no known peer has this block
+	blockStateNew                             // indicates that a peer has reported having this block
+	blockStatePending                         // indicates that this block has been requested from a peer
+	blockStateReceived                        // indicates that this block has been received by a peer
+	blockStateProcessed                       // indicates that this block has been applied
+)
+
+func (e blockState) String() string {
+	switch e {
+	case blockStateUnknown:
+		return "Unknown"
+	case blockStateNew:
+		return "New"
+	case blockStatePending:
+		return "Pending"
+	case blockStateReceived:
+		return "Received"
+	case blockStateProcessed:
+		return "Processed"
+	default:
+		return fmt.Sprintf("invalid blockState: %d", e)
+	}
+}
+
+type peerState int
+
+const (
+	peerStateNew = iota + 1
+	peerStateReady
+	peerStateRemoved
+)
+
+func (e peerState) String() string {
+	switch e {
+	case peerStateNew:
+		return "New"
+	case peerStateReady:
+		return "Ready"
+	case peerStateRemoved:
+		return "Removed"
+	default:
+		panic(fmt.Sprintf("unknown peerState: %d", e))
+	}
+}
+
+type scPeer struct {
+	peerID p2p.ID
+
+	// initialized as New when peer is added, updated to Ready when statusUpdate is received,
+	// updated to Removed when peer is removed
+	state peerState
+
+	base        int64 // updated when statusResponse is received
+	height      int64 // updated when statusResponse is received
+	lastTouched time.Time
+	lastRate    int64 // last receive rate in bytes
+}
+
+func (p scPeer) String() string {
+	return fmt.Sprintf("{state %v, base %d, height %d, lastTouched %v, lastRate %d, id %v}",
+		p.state, p.base, p.height, p.lastTouched, p.lastRate, p.peerID)
+}
+
+func newScPeer(peerID p2p.ID) *scPeer {
+	return &scPeer{
+		peerID:      peerID,
+		state:       peerStateNew,
+		base:        -1,
+		height:      -1,
+		lastTouched: time.Time{},
+	}
+}
+
+// The scheduler keep track of the state of each block and each peer. The
+// scheduler will attempt to schedule new block requests with `trySchedule`
+// events and remove slow peers with `tryPrune` events.
+type scheduler struct {
+	initHeight int64
+
+	// next block that needs to be processed. All blocks with smaller height are
+	// in Processed state.
+	height int64
+
+	// lastAdvance tracks the last time a block execution happened.
+	// syncTimeout is the maximum time the scheduler waits to advance in the fast sync process before finishing.
+	// This covers the cases where there are no peers or all peers have a lower height.
+	lastAdvance time.Time
+	syncTimeout time.Duration
+
+	// a map of peerID to scheduler specific peer struct `scPeer` used to keep
+	// track of peer specific state
+	peers       map[p2p.ID]*scPeer
+	peerTimeout time.Duration // maximum response time from a peer otherwise prune
+	minRecvRate int64         // minimum receive rate from peer otherwise prune
+
+	// the maximum number of blocks that should be New, Received or Pending at any point
+	// in time. This is used to enforce a limit on the blockStates map.
+	targetPending int
+	// a list of blocks to be scheduled (New), Pending or Received. Its length should be
+	// smaller than targetPending.
+	blockStates map[int64]blockState
+
+	// a map of heights to the peer we are waiting a response from
+	pendingBlocks map[int64]p2p.ID
+
+	// the time at which a block was put in blockStatePending
+	pendingTime map[int64]time.Time
+
+	// a map of heights to the peers that put the block in blockStateReceived
+	receivedBlocks map[int64]p2p.ID
+}
+
+func (sc scheduler) String() string {
+	return fmt.Sprintf("ih: %d, bst: %v, peers: %v, pblks: %v, ptm %v, rblks: %v",
+		sc.initHeight, sc.blockStates, sc.peers, sc.pendingBlocks, sc.pendingTime, sc.receivedBlocks)
+}
+
+func newScheduler(initHeight int64, startTime time.Time) *scheduler {
+	sc := scheduler{
+		initHeight:     initHeight,
+		lastAdvance:    startTime,
+		syncTimeout:    60 * time.Second,
+		height:         initHeight,
+		blockStates:    make(map[int64]blockState),
+		peers:          make(map[p2p.ID]*scPeer),
+		pendingBlocks:  make(map[int64]p2p.ID),
+		pendingTime:    make(map[int64]time.Time),
+		receivedBlocks: make(map[int64]p2p.ID),
+		targetPending:  10,               // TODO - pass as param
+		peerTimeout:    15 * time.Second, // TODO - pass as param
+		minRecvRate:    0,                // int64(7680), TODO - pass as param
+	}
+
+	return &sc
+}
+
+func (sc *scheduler) ensurePeer(peerID p2p.ID) *scPeer {
+	if _, ok := sc.peers[peerID]; !ok {
+		sc.peers[peerID] = newScPeer(peerID)
+	}
+	return sc.peers[peerID]
+}
+
+func (sc *scheduler) touchPeer(peerID p2p.ID, time time.Time) error {
+	peer, ok := sc.peers[peerID]
+	if !ok {
+		return fmt.Errorf("couldn't find peer %s", peerID)
+	}
+
+	if peer.state != peerStateReady {
+		return fmt.Errorf("tried to touch peer in state %s, must be Ready", peer.state)
+	}
+
+	peer.lastTouched = time
+
+	return nil
+}
+
+func (sc *scheduler) removePeer(peerID p2p.ID) {
+	peer, ok := sc.peers[peerID]
+	if !ok {
+		return
+	}
+	if peer.state == peerStateRemoved {
+		return
+	}
+
+	for height, pendingPeerID := range sc.pendingBlocks {
+		if pendingPeerID == peerID {
+			sc.setStateAtHeight(height, blockStateNew)
+			delete(sc.pendingTime, height)
+			delete(sc.pendingBlocks, height)
+		}
+	}
+
+	for height, rcvPeerID := range sc.receivedBlocks {
+		if rcvPeerID == peerID {
+			sc.setStateAtHeight(height, blockStateNew)
+			delete(sc.receivedBlocks, height)
+		}
+	}
+
+	// remove the blocks from blockStates if the peer removal causes the max peer height to be lower.
+	peer.state = peerStateRemoved
+	maxPeerHeight := int64(0)
+	for _, otherPeer := range sc.peers {
+		if otherPeer.state != peerStateReady {
+			continue
+		}
+		if otherPeer.peerID != peer.peerID && otherPeer.height > maxPeerHeight {
+			maxPeerHeight = otherPeer.height
+		}
+	}
+	for h := range sc.blockStates {
+		if h > maxPeerHeight {
+			delete(sc.blockStates, h)
+		}
+	}
+}
+
+// check if the blockPool is running low and add new blocks in New state to be requested.
+// This function is called when there is an increase in the maximum peer height or when
+// blocks are processed.
+func (sc *scheduler) addNewBlocks() {
+	if len(sc.blockStates) >= sc.targetPending {
+		return
+	}
+
+	for i := sc.height; i < int64(sc.targetPending)+sc.height; i++ {
+		if i > sc.maxHeight() {
+			break
+		}
+		if sc.getStateAtHeight(i) == blockStateUnknown {
+			sc.setStateAtHeight(i, blockStateNew)
+		}
+	}
+}
+
+func (sc *scheduler) setPeerRange(peerID p2p.ID, base int64, height int64) error {
+	peer := sc.ensurePeer(peerID)
+
+	if peer.state == peerStateRemoved {
+		return nil // noop
+	}
+
+	if height < peer.height {
+		sc.removePeer(peerID)
+		return fmt.Errorf("cannot move peer height lower. from %d to %d", peer.height, height)
+	}
+
+	if base > height {
+		sc.removePeer(peerID)
+		return fmt.Errorf("cannot set peer base higher than its height")
+	}
+
+	peer.base = base
+	peer.height = height
+	peer.state = peerStateReady
+
+	sc.addNewBlocks()
+	return nil
+}
+
+func (sc *scheduler) getStateAtHeight(height int64) blockState {
+	if height < sc.height {
+		return blockStateProcessed
+	} else if state, ok := sc.blockStates[height]; ok {
+		return state
+	} else {
+		return blockStateUnknown
+	}
+}
+
+func (sc *scheduler) getPeersWithHeight(height int64) []p2p.ID {
+	peers := make([]p2p.ID, 0)
+	for _, peer := range sc.peers {
+		if peer.state != peerStateReady {
+			continue
+		}
+		if peer.base <= height && peer.height >= height {
+			peers = append(peers, peer.peerID)
+		}
+	}
+	return peers
+}
+
+func (sc *scheduler) prunablePeers(peerTimout time.Duration, minRecvRate int64, now time.Time) []p2p.ID {
+	prunable := make([]p2p.ID, 0)
+	for peerID, peer := range sc.peers {
+		if peer.state != peerStateReady {
+			continue
+		}
+		if now.Sub(peer.lastTouched) > peerTimout || peer.lastRate < minRecvRate {
+			prunable = append(prunable, peerID)
+		}
+	}
+	// Tests for handleTryPrunePeer() may fail without sort due to range non-determinism
+	sort.Sort(PeerByID(prunable))
+	return prunable
+}
+
+func (sc *scheduler) setStateAtHeight(height int64, state blockState) {
+	sc.blockStates[height] = state
+}
+
+// CONTRACT: peer exists and in Ready state.
+func (sc *scheduler) markReceived(peerID p2p.ID, height int64, size int, now time.Time) error {
+	peer := sc.peers[peerID]
+
+	if state := sc.getStateAtHeight(height); state != blockStatePending || sc.pendingBlocks[height] != peerID {
+		return fmt.Errorf("received block %d from peer %s without being requested", height, peerID)
+	}
+
+	pendingTime, ok := sc.pendingTime[height]
+	if !ok || now.Sub(pendingTime) <= 0 {
+		return fmt.Errorf("clock error: block %d received at %s but requested at %s",
+			height, pendingTime, now)
+	}
+
+	peer.lastRate = int64(size) / now.Sub(pendingTime).Nanoseconds()
+
+	sc.setStateAtHeight(height, blockStateReceived)
+	delete(sc.pendingBlocks, height)
+	delete(sc.pendingTime, height)
+
+	sc.receivedBlocks[height] = peerID
+
+	return nil
+}
+
+func (sc *scheduler) markPending(peerID p2p.ID, height int64, time time.Time) error {
+	state := sc.getStateAtHeight(height)
+	if state != blockStateNew {
+		return fmt.Errorf("block %d should be in blockStateNew but is %s", height, state)
+	}
+
+	peer, ok := sc.peers[peerID]
+	if !ok {
+		return fmt.Errorf("cannot find peer %s", peerID)
+	}
+
+	if peer.state != peerStateReady {
+		return fmt.Errorf("cannot schedule %d from %s in %s", height, peerID, peer.state)
+	}
+
+	if height > peer.height {
+		return fmt.Errorf("cannot request height %d from peer %s that is at height %d",
+			height, peerID, peer.height)
+	}
+
+	if height < peer.base {
+		return fmt.Errorf("cannot request height %d for peer %s with base %d",
+			height, peerID, peer.base)
+	}
+
+	sc.setStateAtHeight(height, blockStatePending)
+	sc.pendingBlocks[height] = peerID
+	sc.pendingTime[height] = time
+
+	return nil
+}
+
+func (sc *scheduler) markProcessed(height int64) error {
+	// It is possible that a peer error or timeout is handled after the processor
+	// has processed the block but before the scheduler received this event, so
+	// when pcBlockProcessed event is received, the block had been requested
+	// again => don't check the block state.
+	sc.lastAdvance = time.Now()
+	sc.height = height + 1
+	delete(sc.pendingBlocks, height)
+	delete(sc.pendingTime, height)
+	delete(sc.receivedBlocks, height)
+	delete(sc.blockStates, height)
+	sc.addNewBlocks()
+	return nil
+}
+
+func (sc *scheduler) allBlocksProcessed() bool {
+	if len(sc.peers) == 0 {
+		return false
+	}
+	return sc.height >= sc.maxHeight()
+}
+
+// returns max peer height or the last processed block, i.e. sc.height
+func (sc *scheduler) maxHeight() int64 {
+	max := sc.height - 1
+	for _, peer := range sc.peers {
+		if peer.state != peerStateReady {
+			continue
+		}
+		if max < peer.height {
+			max = peer.height
+		}
+	}
+	return max
+}
+
+// lowest block in sc.blockStates with state == blockStateNew or -1 if no new blocks
+func (sc *scheduler) nextHeightToSchedule() int64 {
+	var min int64 = math.MaxInt64
+	for height, state := range sc.blockStates {
+		if state == blockStateNew && height < min {
+			min = height
+		}
+	}
+	if min == math.MaxInt64 {
+		min = -1
+	}
+	return min
+}
+
+func (sc *scheduler) pendingFrom(peerID p2p.ID) []int64 {
+	var heights []int64
+	for height, pendingPeerID := range sc.pendingBlocks {
+		if pendingPeerID == peerID {
+			heights = append(heights, height)
+		}
+	}
+	return heights
+}
+
+func (sc *scheduler) selectPeer(height int64) (p2p.ID, error) {
+	peers := sc.getPeersWithHeight(height)
+	if len(peers) == 0 {
+		return "", fmt.Errorf("cannot find peer for height %d", height)
+	}
+
+	// create a map from number of pending requests to a list
+	// of peers having that number of pending requests.
+	pendingFrom := make(map[int][]p2p.ID)
+	for _, peerID := range peers {
+		numPending := len(sc.pendingFrom(peerID))
+		pendingFrom[numPending] = append(pendingFrom[numPending], peerID)
+	}
+
+	// find the set of peers with minimum number of pending requests.
+	var minPending int64 = math.MaxInt64
+	for mp := range pendingFrom {
+		if int64(mp) < minPending {
+			minPending = int64(mp)
+		}
+	}
+
+	sort.Sort(PeerByID(pendingFrom[int(minPending)]))
+	return pendingFrom[int(minPending)][0], nil
+}
+
+// PeerByID is a list of peers sorted by peerID.
+type PeerByID []p2p.ID
+
+func (peers PeerByID) Len() int {
+	return len(peers)
+}
+func (peers PeerByID) Less(i, j int) bool {
+	return bytes.Compare([]byte(peers[i]), []byte(peers[j])) == -1
+}
+
+func (peers PeerByID) Swap(i, j int) {
+	peers[i], peers[j] = peers[j], peers[i]
+}
+
+// Handlers
+
+// This handler gets the block, performs some validation and then passes it on to the processor.
+func (sc *scheduler) handleBlockResponse(event bcBlockResponse) (Event, error) {
+	err := sc.touchPeer(event.peerID, event.time)
+	if err != nil {
+		// peer does not exist OR not ready
+		return noOp, nil
+	}
+
+	err = sc.markReceived(event.peerID, event.block.Height, event.block.Size(), event.time)
+	if err != nil {
+		sc.removePeer(event.peerID)
+		return scPeerError{peerID: event.peerID, reason: err}, nil
+	}
+
+	return scBlockReceived{peerID: event.peerID, block: event.block}, nil
+}
+
+func (sc *scheduler) handleNoBlockResponse(event bcNoBlockResponse) (Event, error) {
+	// No such peer or peer was removed.
+	peer, ok := sc.peers[event.peerID]
+	if !ok || peer.state == peerStateRemoved {
+		return noOp, nil
+	}
+
+	// The peer may have been just removed due to errors, low speed or timeouts.
+	sc.removePeer(event.peerID)
+
+	return scPeerError{peerID: event.peerID,
+		reason: fmt.Errorf("peer %v with base %d height %d claims no block for %d",
+			event.peerID, peer.base, peer.height, event.height)}, nil
+}
+
+func (sc *scheduler) handleBlockProcessed(event pcBlockProcessed) (Event, error) {
+	if event.height != sc.height {
+		panic(fmt.Sprintf("processed height %d, but expected height %d", event.height, sc.height))
+	}
+
+	err := sc.markProcessed(event.height)
+	if err != nil {
+		return scSchedulerFail{reason: err}, nil
+	}
+
+	if sc.allBlocksProcessed() {
+		return scFinishedEv{reason: "processed all blocks"}, nil
+	}
+
+	return noOp, nil
+}
+
+// Handles an error from the processor. The processor had already cleaned the blocks from
+// the peers included in this event. Just attempt to remove the peers.
+func (sc *scheduler) handleBlockProcessError(event pcBlockVerificationFailure) (Event, error) {
+	// The peers may have been just removed due to errors, low speed or timeouts.
+	sc.removePeer(event.firstPeerID)
+	if event.firstPeerID != event.secondPeerID {
+		sc.removePeer(event.secondPeerID)
+	}
+
+	if sc.allBlocksProcessed() {
+		return scFinishedEv{reason: "error on last block"}, nil
+	}
+
+	return noOp, nil
+}
+
+func (sc *scheduler) handleAddNewPeer(event bcAddNewPeer) (Event, error) {
+	sc.ensurePeer(event.peerID)
+	return noOp, nil
+}
+
+func (sc *scheduler) handleRemovePeer(event bcRemovePeer) (Event, error) {
+	sc.removePeer(event.peerID)
+
+	if sc.allBlocksProcessed() {
+		return scFinishedEv{reason: "removed peer"}, nil
+	}
+
+	// Return scPeerError so the peer (and all associated blocks) is removed from
+	// the processor.
+	return scPeerError{peerID: event.peerID, reason: errors.New("peer was stopped")}, nil
+}
+
+func (sc *scheduler) handleTryPrunePeer(event rTryPrunePeer) (Event, error) {
+	// Check behavior of peer responsible to deliver block at sc.height.
+	timeHeightAsked, ok := sc.pendingTime[sc.height]
+	if ok && time.Since(timeHeightAsked) > sc.peerTimeout {
+		// A request was sent to a peer for block at sc.height but a response was not received
+		// from that peer within sc.peerTimeout. Remove the peer. This is to ensure that a peer
+		// will be timed out even if it sends blocks at higher heights but prevents progress by
+		// not sending the block at current height.
+		sc.removePeer(sc.pendingBlocks[sc.height])
+	}
+
+	prunablePeers := sc.prunablePeers(sc.peerTimeout, sc.minRecvRate, event.time)
+	if len(prunablePeers) == 0 {
+		return noOp, nil
+	}
+	for _, peerID := range prunablePeers {
+		sc.removePeer(peerID)
+	}
+
+	// If all blocks are processed we should finish.
+	if sc.allBlocksProcessed() {
+		return scFinishedEv{reason: "after try prune"}, nil
+	}
+
+	return scPeersPruned{peers: prunablePeers}, nil
+}
+
+func (sc *scheduler) handleResetState(event bcResetState) (Event, error) {
+	initHeight := event.state.LastBlockHeight + 1
+	if initHeight == 1 {
+		initHeight = event.state.InitialHeight
+	}
+	sc.initHeight = initHeight
+	sc.height = initHeight
+	sc.lastAdvance = time.Now()
+	sc.addNewBlocks()
+	return noOp, nil
+}
+
+func (sc *scheduler) handleTrySchedule(event rTrySchedule) (Event, error) {
+	if time.Since(sc.lastAdvance) > sc.syncTimeout {
+		return scFinishedEv{reason: "timeout, no advance"}, nil
+	}
+
+	nextHeight := sc.nextHeightToSchedule()
+	if nextHeight == -1 {
+		return noOp, nil
+	}
+
+	bestPeerID, err := sc.selectPeer(nextHeight)
+	if err != nil {
+		return scSchedulerFail{reason: err}, nil
+	}
+	if err := sc.markPending(bestPeerID, nextHeight, event.time); err != nil {
+		return scSchedulerFail{reason: err}, nil // XXX: peerError might be more appropriate
+	}
+	return scBlockRequest{peerID: bestPeerID, height: nextHeight}, nil
+
+}
+
+func (sc *scheduler) handleStatusResponse(event bcStatusResponse) (Event, error) {
+	err := sc.setPeerRange(event.peerID, event.base, event.height)
+	if err != nil {
+		return scPeerError{peerID: event.peerID, reason: err}, nil
+	}
+	return noOp, nil
+}
+
+func (sc *scheduler) handle(event Event) (Event, error) {
+	switch event := event.(type) {
+	case bcResetState:
+		nextEvent, err := sc.handleResetState(event)
+		return nextEvent, err
+	case bcStatusResponse:
+		nextEvent, err := sc.handleStatusResponse(event)
+		return nextEvent, err
+	case bcBlockResponse:
+		nextEvent, err := sc.handleBlockResponse(event)
+		return nextEvent, err
+	case bcNoBlockResponse:
+		nextEvent, err := sc.handleNoBlockResponse(event)
+		return nextEvent, err
+	case rTrySchedule:
+		nextEvent, err := sc.handleTrySchedule(event)
+		return nextEvent, err
+	case bcAddNewPeer:
+		nextEvent, err := sc.handleAddNewPeer(event)
+		return nextEvent, err
+	case bcRemovePeer:
+		nextEvent, err := sc.handleRemovePeer(event)
+		return nextEvent, err
+	case rTryPrunePeer:
+		nextEvent, err := sc.handleTryPrunePeer(event)
+		return nextEvent, err
+	case pcBlockProcessed:
+		nextEvent, err := sc.handleBlockProcessed(event)
+		return nextEvent, err
+	case pcBlockVerificationFailure:
+		nextEvent, err := sc.handleBlockProcessError(event)
+		return nextEvent, err
+	default:
+		return scSchedulerFail{reason: fmt.Errorf("unknown event %v", event)}, nil
+	}
+}

blockchain/v2/types.go

@@ -0,0 +1,65 @@
+package v2
+
+import (
+	"github.com/Workiva/go-datastructures/queue"
+)
+
+// Event is the type that can be added to the priority queue.
+type Event queue.Item
+
+type priority interface {
+	Compare(other queue.Item) int
+	Priority() int
+}
+
+type priorityLow struct{}
+type priorityNormal struct{}
+type priorityHigh struct{}
+
+func (p priorityLow) Priority() int {
+	return 1
+}
+
+func (p priorityNormal) Priority() int {
+	return 2
+}
+
+func (p priorityHigh) Priority() int {
+	return 3
+}
+
+func (p priorityLow) Compare(other queue.Item) int {
+	op := other.(priority)
+	if p.Priority() > op.Priority() {
+		return 1
+	} else if p.Priority() == op.Priority() {
+		return 0
+	}
+	return -1
+}
+
+func (p priorityNormal) Compare(other queue.Item) int {
+	op := other.(priority)
+	if p.Priority() > op.Priority() {
+		return 1
+	} else if p.Priority() == op.Priority() {
+		return 0
+	}
+	return -1
+}
+
+func (p priorityHigh) Compare(other queue.Item) int {
+	op := other.(priority)
+	if p.Priority() > op.Priority() {
+		return 1
+	} else if p.Priority() == op.Priority() {
+		return 0
+	}
+	return -1
+}
+
+type noOpEvent struct {
+	priorityLow
+}
+
+var noOp = noOpEvent{}

cmd/tendermint/commands/debug/dump.go

@@ -3,7 +3,6 @@ package debug
 import (
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"time"
@@ -82,7 +81,7 @@ func dumpCmdHandler(_ *cobra.Command, args []string) error {
 func dumpDebugData(outDir string, conf *cfg.Config, rpc *rpchttp.HTTP) {
 	start := time.Now().UTC()
 
-	tmpDir, err := ioutil.TempDir(outDir, "tendermint_debug_tmp")
+	tmpDir, err := os.MkdirTemp(outDir, "tendermint_debug_tmp")
 	if err != nil {
 		logger.Error("failed to create temporary directory", "dir", tmpDir, "error", err)
 		return

cmd/tendermint/commands/debug/io.go

@@ -5,7 +5,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
-	"io/ioutil"
 	"os"
 	"path"
 	"path/filepath"
@@ -68,7 +67,6 @@ func zipDir(src, dest string) error {
 		_, err = io.Copy(headerWriter, file)
 		return err
 	})
-
 }
 
 // copyFile copies a file from src to dest and returns an error upon failure. The
@@ -111,5 +109,5 @@ func writeStateJSONToFile(state interface{}, dir, filename string) error {
 		return fmt.Errorf("failed to encode state dump: %w", err)
 	}
 
-	return ioutil.WriteFile(path.Join(dir, filename), stateJSON, os.ModePerm)
+	return os.WriteFile(path.Join(dir, filename), stateJSON, os.ModePerm)
 }

cmd/tendermint/commands/debug/kill.go

@@ -3,7 +3,6 @@ package debug
 import (
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"os/exec"
 	"path/filepath"
@@ -56,7 +55,7 @@ func killCmdHandler(cmd *cobra.Command, args []string) error {
 
 	// Create a temporary directory which will contain all the state dumps and
 	// relevant files and directories that will be compressed into a file.
-	tmpDir, err := ioutil.TempDir(os.TempDir(), "tendermint_debug_tmp")
+	tmpDir, err := os.MkdirTemp(os.TempDir(), "tendermint_debug_tmp")
 	if err != nil {
 		return fmt.Errorf("failed to create temporary directory: %w", err)
 	}
@@ -105,7 +104,7 @@ func killProc(pid uint64, dir string) error {
 	// pipe STDERR output from tailing the Tendermint process to a file
 	//
 	// NOTE: This will only work on UNIX systems.
-	cmd := exec.Command("tail", "-f", fmt.Sprintf("/proc/%d/fd/2", pid)) // nolint: gosec
+	cmd := exec.Command("tail", "-f", fmt.Sprintf("/proc/%d/fd/2", pid)) //nolint: gosec
 
 	outFile, err := os.Create(filepath.Join(dir, "stacktrace.out"))
 	if err != nil {

cmd/tendermint/commands/debug/util.go

@@ -3,7 +3,7 @@ package debug
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"os"
 	"path"
@@ -67,16 +67,17 @@ func copyConfig(home, dir string) error {
 func dumpProfile(dir, addr, profile string, debug int) error {
 	endpoint := fmt.Sprintf("%s/debug/pprof/%s?debug=%d", addr, profile, debug)
 
-	resp, err := http.Get(endpoint) // nolint: gosec
+	//nolint:gosec,nolintlint
+	resp, err := http.Get(endpoint)
 	if err != nil {
 		return fmt.Errorf("failed to query for %s profile: %w", profile, err)
 	}
 	defer resp.Body.Close()
 
-	body, err := ioutil.ReadAll(resp.Body)
+	body, err := io.ReadAll(resp.Body)
 	if err != nil {
 		return fmt.Errorf("failed to read %s profile response body: %w", profile, err)
 	}
 
-	return ioutil.WriteFile(path.Join(dir, fmt.Sprintf("%s.out", profile)), body, os.ModePerm)
+	return os.WriteFile(path.Join(dir, fmt.Sprintf("%s.out", profile)), body, os.ModePerm)
 }

cmd/tendermint/commands/init.go

@@ -14,7 +14,7 @@ import (
 	tmtime "github.com/tendermint/tendermint/types/time"
 )
 
-// InitFilesCmd initializes a fresh Tendermint Core instance.
+// InitFilesCmd initialises a fresh Tendermint Core instance.
 var InitFilesCmd = &cobra.Command{
 	Use:   "init",
 	Short: "Initialize Tendermint",

cmd/tendermint/commands/light.go

@@ -101,7 +101,7 @@ func init() {
 }
 
 func runProxy(cmd *cobra.Command, args []string) error {
-	// Initialize logger.
+	// Initialise logger.
 	logger := log.NewTMLogger(log.NewSyncWriter(os.Stdout))
 	var option log.Option
 	if verbose {