ci: deploy pull requests to staging server (#24)

.github/workflows/build-docker.yml

@@ -16,11 +16,13 @@ env:
   NGINX_IMAGE_NAME: ${{ github.repository }}-nginx
 
 jobs:
-  build-test-and-deploy:
+  build:
     runs-on: ubuntu-latest
     permissions:
       contents: write
       packages: write
+      pull-requests: write
+      actions: write
 
     steps:
       - name: Checkout repository
@@ -32,7 +34,6 @@ jobs:
         uses: docker/setup-buildx-action@v3
 
       - name: Log in to GitHub Container Registry
-        if: github.event_name != 'pull_request'
         uses: docker/login-action@v3
         with:
           registry: ${{ env.REGISTRY }}
@@ -47,7 +48,7 @@ jobs:
           tags: |
             type=ref,event=branch
             type=ref,event=pr
-            type=sha,prefix={{branch}}-
+            type=sha,prefix={{branch}}-,enable={{is_default_branch}}
             type=raw,value=latest,enable={{is_default_branch}}
 
       - name: Extract metadata for nginx image
@@ -58,7 +59,7 @@ jobs:
           tags: |
             type=ref,event=branch
             type=ref,event=pr
-            type=sha,prefix={{branch}}-
+            type=sha,prefix={{branch}}-,enable={{is_default_branch}}
             type=raw,value=latest,enable={{is_default_branch}}
 
       - name: Build application image
@@ -95,9 +96,25 @@ jobs:
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
           publish_dir: ./docs-output
-          destination_dir: ${{ github.ref == 'refs/heads/main' && '.' || github.ref_name }}
+          destination_dir: ${{ github.ref == 'refs/heads/main' && '.' || github.head_ref || github.ref_name }}
           keep_files: true
 
+      - name: Comment documentation link
+        if: github.event_name == 'pull_request'
+        uses: marocchino/sticky-pull-request-comment@v2
+        with:
+          header: deployment
+          message: |
+            📚 **Documentation deployed!**
+
+            **Documentation:** https://${{ github.repository_owner }}.github.io/${{ github.event.repository.name }}/${{ github.head_ref }}/
+
+            **Docker Images:**
+            - App: `${{ env.REGISTRY }}/${{ env.APP_IMAGE_NAME }}:pr-${{ github.event.pull_request.number }}`
+            - Nginx: `${{ env.REGISTRY }}/${{ env.NGINX_IMAGE_NAME }}:pr-${{ github.event.pull_request.number }}`
+
+            Add the `awaiting-deployment` label to deploy this PR to a staging server.
+
       - name: Run tests
         run: make test-only
 
@@ -111,7 +128,6 @@ jobs:
           fi
 
       - name: Tag and push application image
-        if: github.event_name != 'pull_request'
         run: |
           # Tag the built image with all required tags
           echo "${{ steps.meta-app.outputs.tags }}" | while read -r tag; do
@@ -120,7 +136,6 @@ jobs:
           done
 
       - name: Build and push nginx image
-        if: github.event_name != 'pull_request'
         uses: docker/build-push-action@v5
         with:
           context: docker/production/nginx
@@ -138,10 +153,40 @@ jobs:
             BUILDKIT_INLINE_CACHE=1
 
       - name: Output image tags
-        if: github.event_name != 'pull_request'
         run: |
           echo "Application image tags:"
           echo "${{ steps.meta-app.outputs.tags }}"
           echo ""
           echo "Nginx image tags:"
           echo "${{ steps.meta-nginx.outputs.tags }}"
+
+      - name: Check for awaiting-deployment label and trigger deploy
+        if: github.event_name == 'pull_request'
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const prNumber = context.payload.pull_request.number;
+
+            // Check if PR has awaiting-deployment label
+            const { data: pr } = await github.rest.pulls.get({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              pull_number: prNumber
+            });
+
+            const hasLabel = pr.labels.some(label => label.name === 'awaiting-deployment');
+
+            if (hasLabel) {
+              console.log('PR has awaiting-deployment label, triggering deployment');
+              await github.rest.actions.createWorkflowDispatch({
+                owner: context.repo.owner,
+                repo: context.repo.repo,
+                workflow_id: 'deploy-pr.yml',
+                ref: context.payload.pull_request.head.ref,
+                inputs: {
+                  pr_number: prNumber.toString()
+                }
+              });
+            } else {
+              console.log('PR does not have awaiting-deployment label, skipping deployment');
+            }

.github/workflows/check-deployment.yml

@@ -0,0 +1,81 @@
+name: Check Deployment Readiness
+
+on:
+  pull_request:
+    types: [labeled]
+
+jobs:
+  check-and-deploy:
+    runs-on: ubuntu-latest
+    if: github.event.label.name == 'awaiting-deployment'
+    permissions:
+      actions: write
+      pull-requests: read
+      contents: write
+
+    steps:
+      - name: Check build workflow status
+        id: check
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const prNumber = context.payload.pull_request.number;
+            const headSha = context.payload.pull_request.head.sha;
+
+            console.log(`Checking build status for PR #${prNumber}, commit ${headSha}`);
+
+            // Use Check Runs API to get the status of the build workflow
+            const { data: checkRuns } = await github.rest.checks.listForRef({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              ref: headSha,
+              check_name: 'build'
+            });
+
+            console.log(`Found ${checkRuns.total_count} check runs for 'build'`);
+
+            if (checkRuns.total_count === 0) {
+              console.log('No build check found for this commit');
+              core.setOutput('should_deploy', 'false');
+              core.setOutput('reason', 'No build check found');
+              return;
+            }
+
+            const buildCheck = checkRuns.check_runs[0];
+            console.log(`Build check status: ${buildCheck.status}, conclusion: ${buildCheck.conclusion}`);
+
+            // Check if build is still running
+            if (buildCheck.status !== 'completed') {
+              console.log('Build check is still running');
+              core.setOutput('should_deploy', 'false');
+              core.setOutput('reason', 'Build check is still running');
+              return;
+            }
+
+            // Check if build failed
+            if (buildCheck.conclusion !== 'success') {
+              console.log(`Build check failed with conclusion: ${buildCheck.conclusion}`);
+              core.setOutput('should_deploy', 'false');
+              core.setOutput('reason', `Build check ${buildCheck.conclusion}`);
+              return;
+            }
+
+            // Build completed successfully
+            console.log('Build check completed successfully, ready to deploy');
+            core.setOutput('should_deploy', 'true');
+
+      - name: Trigger deployment
+        if: steps.check.outputs.should_deploy == 'true'
+        uses: actions/github-script@v7
+        with:
+          script: |
+            await github.rest.actions.createWorkflowDispatch({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              workflow_id: 'deploy-pr.yml',
+              ref: context.payload.pull_request.head.ref,
+              inputs: {
+                pr_number: context.payload.pull_request.number.toString()
+              }
+            });
+            console.log('Deployment workflow triggered');