config: backport the rename of fastsync to blocksync (#9259)

This is largely a cherry pick of #6755 with some additional fixups added where detected. 
This change moves the blockchain package to a package called blocksync. Additionally, it renames the relevant uses of the term `fastsync` to `blocksync`.

closes: #9227 

#### PR checklist

- [ ] Tests written/updated, or no tests needed
- [x] `CHANGELOG_PENDING.md` updated, or no changelog entry needed
- [x] Updated relevant documentation (`docs/`) and code comments, or no
      documentation updates needed

blocksync/pool_test.go

@@ -0,0 +1,242 @@
+package blocksync
+
+import (
+	"fmt"
+	"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 init() {
+	peerTimeout = 2 * time.Second
+}
+
+type testPeer struct {
+	id        p2p.ID
+	base      int64
+	height    int64
+	inputChan chan inputData // make sure each peer's data is sequential
+}
+
+type inputData struct {
+	t       *testing.T
+	pool    *BlockPool
+	request BlockRequest
+}
+
+func (p testPeer) runInputRoutine() {
+	go func() {
+		for input := range p.inputChan {
+			p.simulateInput(input)
+		}
+	}()
+}
+
+// Request desired, pretend like we got the block immediately.
+func (p testPeer) simulateInput(input inputData) {
+	block := &types.Block{Header: types.Header{Height: input.request.Height}}
+	input.pool.AddBlock(input.request.PeerID, block, 123)
+	// TODO: uncommenting this creates a race which is detected by:
+	// https://github.com/golang/go/blob/2bd767b1022dd3254bcec469f0ee164024726486/src/testing/testing.go#L854-L856
+	// see: https://github.com/tendermint/tendermint/issues/3390#issue-418379890
+	// input.t.Logf("Added block from peer %v (height: %v)", input.request.PeerID, input.request.Height)
+}
+
+type testPeers map[p2p.ID]testPeer
+
+func (ps testPeers) start() {
+	for _, v := range ps {
+		v.runInputRoutine()
+	}
+}
+
+func (ps testPeers) stop() {
+	for _, v := range ps {
+		close(v.inputChan)
+	}
+}
+
+func makePeers(numPeers int, minHeight, maxHeight int64) testPeers {
+	peers := make(testPeers, numPeers)
+	for i := 0; i < numPeers; i++ {
+		peerID := p2p.ID(tmrand.Str(12))
+		height := minHeight + tmrand.Int63n(maxHeight-minHeight)
+		base := minHeight + int64(i)
+		if base > height {
+			base = height
+		}
+		peers[peerID] = testPeer{peerID, base, height, make(chan inputData, 10)}
+	}
+	return peers
+}
+
+func TestBlockPoolBasic(t *testing.T) {
+	start := int64(42)
+	peers := makePeers(10, start+1, 1000)
+	errorsCh := make(chan peerError, 1000)
+	requestsCh := make(chan BlockRequest, 1000)
+	pool := NewBlockPool(start, requestsCh, errorsCh)
+	pool.SetLogger(log.TestingLogger())
+
+	err := pool.Start()
+	if err != nil {
+		t.Error(err)
+	}
+
+	t.Cleanup(func() {
+		if err := pool.Stop(); err != nil {
+			t.Error(err)
+		}
+	})
+
+	peers.start()
+	defer peers.stop()
+
+	// Introduce each peer.
+	go func() {
+		for _, peer := range peers {
+			pool.SetPeerRange(peer.id, peer.base, peer.height)
+		}
+	}()
+
+	// Start a goroutine to pull blocks
+	go func() {
+		for {
+			if !pool.IsRunning() {
+				return
+			}
+			first, second := pool.PeekTwoBlocks()
+			if first != nil && second != nil {
+				pool.PopRequest()
+			} else {
+				time.Sleep(1 * time.Second)
+			}
+		}
+	}()
+
+	// Pull from channels
+	for {
+		select {
+		case err := <-errorsCh:
+			t.Error(err)
+		case request := <-requestsCh:
+			t.Logf("Pulled new BlockRequest %v", request)
+			if request.Height == 300 {
+				return // Done!
+			}
+
+			peers[request.PeerID].inputChan <- inputData{t, pool, request}
+		}
+	}
+}
+
+func TestBlockPoolTimeout(t *testing.T) {
+	start := int64(42)
+	peers := makePeers(10, start+1, 1000)
+	errorsCh := make(chan peerError, 1000)
+	requestsCh := make(chan BlockRequest, 1000)
+	pool := NewBlockPool(start, requestsCh, errorsCh)
+	pool.SetLogger(log.TestingLogger())
+	err := pool.Start()
+	if err != nil {
+		t.Error(err)
+	}
+	t.Cleanup(func() {
+		if err := pool.Stop(); err != nil {
+			t.Error(err)
+		}
+	})
+
+	for _, peer := range peers {
+		t.Logf("Peer %v", peer.id)
+	}
+
+	// Introduce each peer.
+	go func() {
+		for _, peer := range peers {
+			pool.SetPeerRange(peer.id, peer.base, peer.height)
+		}
+	}()
+
+	// Start a goroutine to pull blocks
+	go func() {
+		for {
+			if !pool.IsRunning() {
+				return
+			}
+			first, second := pool.PeekTwoBlocks()
+			if first != nil && second != nil {
+				pool.PopRequest()
+			} else {
+				time.Sleep(1 * time.Second)
+			}
+		}
+	}()
+
+	// Pull from channels
+	counter := 0
+	timedOut := map[p2p.ID]struct{}{}
+	for {
+		select {
+		case err := <-errorsCh:
+			t.Log(err)
+			// consider error to be always timeout here
+			if _, ok := timedOut[err.peerID]; !ok {
+				counter++
+				if counter == len(peers) {
+					return // Done!
+				}
+			}
+		case request := <-requestsCh:
+			t.Logf("Pulled new BlockRequest %+v", request)
+		}
+	}
+}
+
+func TestBlockPoolRemovePeer(t *testing.T) {
+	peers := make(testPeers, 10)
+	for i := 0; i < 10; i++ {
+		peerID := p2p.ID(fmt.Sprintf("%d", i+1))
+		height := int64(i + 1)
+		peers[peerID] = testPeer{peerID, 0, height, make(chan inputData)}
+	}
+	requestsCh := make(chan BlockRequest)
+	errorsCh := make(chan peerError)
+
+	pool := NewBlockPool(1, requestsCh, errorsCh)
+	pool.SetLogger(log.TestingLogger())
+	err := pool.Start()
+	require.NoError(t, err)
+	t.Cleanup(func() {
+		if err := pool.Stop(); err != nil {
+			t.Error(err)
+		}
+	})
+
+	// add peers
+	for peerID, peer := range peers {
+		pool.SetPeerRange(peerID, peer.base, peer.height)
+	}
+	assert.EqualValues(t, 10, pool.MaxPeerHeight())
+
+	// remove not-existing peer
+	assert.NotPanics(t, func() { pool.RemovePeer(p2p.ID("Superman")) })
+
+	// remove peer with biggest height
+	pool.RemovePeer(p2p.ID("10"))
+	assert.EqualValues(t, 9, pool.MaxPeerHeight())
+
+	// remove all peers
+	for peerID := range peers {
+		pool.RemovePeer(peerID)
+	}
+
+	assert.EqualValues(t, 0, pool.MaxPeerHeight())
+}