doc on steps

deployments/cloudbuild.yaml

@@ -1,20 +1,22 @@
 steps:
 
+# pull latest code and test
 - name: 'golang:latest'
   id: Test
   entrypoint: /bin/sh
   args: ['-c','export GO111MODULE=on','go mod download','go test ./... -v']
 
-# TODO: replace Build, Push, Deploy with ko
-
+# build image
 - name: 'gcr.io/cloud-builders/docker'
   id: Build
   args: ['build','-t','gcr.io/${PROJECT_ID}/${_APP_NAME}:${SHORT_SHA}','.']
 
+# push image to gcr
 - name: 'gcr.io/cloud-builders/docker'
   id: Push
   args: ['push','gcr.io/${PROJECT_ID}/${_APP_NAME}:${SHORT_SHA}']
 
+# update manifest with few env var (mainly release tag)
 - name: 'gcr.io/cloud-builders/gcloud'
   id: Manifest
   entrypoint: /bin/sh
@@ -25,6 +27,7 @@ steps:
       's/PROJECT_ID/${PROJECT_ID}/g; s/RELEASE_TAG/${TAG_NAME}/g; s/IMAGE_SHA/${SHORT_SHA}/g' \
       deployments/service.yaml > deployments/final.yaml
 
+# deploy service to Knative cluster using the above gen'd manifest
 - name: 'gcr.io/cloud-builders/kubectl'
   id: Deploy
   args: ['apply','-f','deployments/final.yaml']