Save current deployment tag for every environment (#332)

* Save release tag during deployment

* Save current tag for every environment

Store tag of the current deployment in each environment.
This is used by the server-sql compatibility test.

* Save current tag for every environment

Store tag of the current deployment in each environment.
This is used by the server-sql compatibility test.

release/cloudbuild-deploy.yaml

@@ -1,13 +1,13 @@
 # To run the build locally, install cloud-build-local first.
 # Then run:
-# cloud-build-local --config=cloudbuild-deploy-beam.yaml --dryrun=false \
+# cloud-build-local --config=cloudbuild-deploy.yaml --dryrun=false \
 # --substitutions=TAG_NAME=[TAG],_ENV=[ENV] ..
 #
 # This will deploy Beam pipelines to GCS for the PROJECT_ID defined in gcloud
 # tool.
 #
 # To manually trigger a build on GCB, run:
-# gcloud builds submit --config=cloudbuild-deploy-beam.yaml \
+# gcloud builds submit --config=cloudbuild-deploy.yaml \
 # --substitutions=TAG_NAME=[TAG],_ENV=[ENV] ..
 #
 # To trigger a build automatically, follow the instructions below and add a trigger:
@@ -46,6 +46,17 @@ steps:
   - --credential
   - tool-credential.json
   - deploy_invoicing_pipeline
+# Save the deployed tag for the current environment on GCS. Because of b/137891685
+# which causes the for-loop in the next step to fail, this may not be the last step.
+# TODO(weiminyu): do this in last step, and use 'artifacts' section to upload the tag.
+- name: 'gcr.io/${PROJECT_ID}/builder:latest'
+  entrypoint: /bin/bash
+  args:
+  - -c
+  - |
+    set -e
+    echo ${TAG_NAME} | \
+      gsutil cp - gs://${PROJECT_ID}-deploy/deployed_tags/nomulus.${_ENV}.tag
 # Deploy the GAE config files.
 # First authorize the gcloud tool to use the credential json file, then
 # download and unzip the tarball that contains the relevant config files