08 — Deploy automatically when you merge to main

Category: Continuous Deployment · Priority: High · Step: 9

Close the loop: a successful merge to main triggers a deploy. This is full CD.

🎯 What is this task?

You've built, tested, and published. The final piece is deployment: when code lands on main and the image is published, automatically tell your host (e.g. Render from Project 1) to pull the new image and go live — with zero manual steps.

🔗 Builds on: Project 1 Render deploy + lesson 06 (publish to GHCR).

🤖 AI Prompt

"Show me how to trigger a Render deploy from GitHub Actions using a deploy hook URL stored as a secret, only after my publish job succeeds. Use needs: to chain jobs."

📋 Step-by-step

Chain a deploy job after publish using needs::

  deploy:
    runs-on: ubuntu-latest
    needs: publish              # only run if publish succeeded
    if: github.ref == 'refs/heads/main'
    steps:
      - name: Trigger Render deploy
        run: curl -fsSL "${{ secrets.RENDER_DEPLOY_HOOK }}"

• needs: publish → deploy waits for publish and runs only if it passed.
• RENDER_DEPLOY_HOOK is a secret URL from Render → Settings → Deploy Hook.
• Hitting that URL tells Render to pull the latest image and redeploy.

The full pipeline now: push → test → build → publish → deploy, all automatic. That's CI/CD.

✅ Done when

• A deploy job runs only after publish succeeds (needs:)
• Merging to main updates the live site with no manual steps
• You can describe the full push-to-production pipeline end to end