ci(frontend-deploy): announce a deploy when it starts

.github/actions/notify-slack-deploy/action.yml

@@ -15,10 +15,11 @@ inputs:
     description: The environment that was deployed to.
     required: false
     default: production
-  conclusion:
+  state:
     description: >
-      The deploy run's conclusion, straight from workflow_run. Only success and
-      cancelled get their own copy; anything else reads as a failure.
+      in_progress before the deploy runs, otherwise the production job's
+      result. Only in_progress, success and cancelled get their own copy;
+      anything else reads as a failure.
     required: true
   commit_sha:
     description: The commit that was deployed.
@@ -47,7 +48,7 @@ runs:
         SERVICE: ${{ inputs.service }}
         APP_URL: ${{ inputs.app_url }}
         ENVIRONMENT: ${{ inputs.environment }}
-        CONCLUSION: ${{ inputs.conclusion }}
+        STATE: ${{ inputs.state }}
         COMMIT_SHA: ${{ inputs.commit_sha }}
         ACTOR: ${{ inputs.actor }}
         RUN_URL: ${{ inputs.run_url }}
@@ -77,7 +78,7 @@ runs:
         jq -n \
           --arg service "$SERVICE" \
           --arg environment "$ENVIRONMENT" \
-          --arg conclusion "$CONCLUSION" \
+          --arg state "$STATE" \
           --arg short_sha "${COMMIT_SHA:0:7}" \
           --arg actor "$ACTOR" \
           --arg app_url "$APP_URL" \

.github/actions/notify-slack-deploy/payload.jq

@@ -3,16 +3,23 @@
 
 ($environment | (.[0:1] | ascii_upcase) + .[1:]) as $env_name |
 
-# Only success and cancelled need their own words. Everything else GitHub
-# reports, timed_out and skipped included, means the deploy did not happen.
-(if $conclusion == "success" then
+# Only in_progress, success and cancelled need their own words. Everything
+# else, timed_out and skipped included, means the deploy did not happen.
+(if $state == "in_progress" then
+  {
+    headline: "⏳ \($service) deploying to \($environment)",
+    body: "Tests and deploy are running. \($env_name) is still on the previous release.",
+    actor_label: "Pushed by",
+    link_app: false
+  }
+elif $state == "success" then
   {
     headline: "🚀 \($service) deployed to \($environment)",
     body: "🧪 *\($env_name) smoke test required*\n\nPlease verify the application directly in \($environment).",
     actor_label: "Deployed by",
     link_app: true
   }
-elif $conclusion == "cancelled" then
+elif $state == "cancelled" then
   {
     headline: "⏭️ \($service) deploy to \($environment) stopped",
     # run-tests cancels itself in progress when the next commit lands on main,

.github/workflows/frontend-deploy-production.yml

@@ -9,6 +9,35 @@ on:
       - .github/**
 
 jobs:
+  notify-production-deploy-started:
+    name: Notify Production Deploy Started
+    # No needs, so this lands within seconds of the push. Knowing a deploy is
+    # in flight is only useful while it still is.
+    runs-on: ubuntu-latest
+    permissions:
+      # Enough to resolve the local action below.
+      contents: read
+
+    steps:
+      - name: Cloning repo
+        uses: actions/checkout@fbc6f3992d24b796d5a048ff273f7fcc4a7b6c09 # v5.1.0
+        with:
+          # Nothing runs git after this, so the token need not persist.
+          persist-credentials: false
+
+      - name: Notify Slack
+        # A Slack outage must not hold up a deploy.
+        continue-on-error: true
+        uses: ./.github/actions/notify-slack-deploy
+        with:
+          webhook_url: ${{ secrets.SLACK_FRONTEND_DEPLOY_WEBHOOK }}
+          service: Frontend
+          app_url: https://app.flagsmith.com
+          state: in_progress
+          commit_sha: ${{ github.sha }}
+          actor: ${{ github.actor }}
+          run_url: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}
+
   run-unit-tests:
     runs-on: ubuntu-latest
     name: Run Unit Tests
@@ -136,7 +165,7 @@ jobs:
           webhook_url: ${{ secrets.SLACK_FRONTEND_DEPLOY_WEBHOOK }}
           service: Frontend
           app_url: https://app.flagsmith.com
-          conclusion: ${{ steps.outcome.outputs.conclusion }}
+          state: ${{ steps.outcome.outputs.conclusion }}
           commit_sha: ${{ github.sha }}
           actor: ${{ github.actor }}
           run_url: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}