Cycle 8: CI/CD - Automated Deployment

What is CI/CD?

CI/CD is a methodology for automating the process from code changes to deployment.

CI (Continuous Integration)

Frequently integrate code changes and automatically verify them

Code push

Automatic build

Automatic testing

CD (Continuous Deployment)

Automatically deploy verified code to production

Build success

Automatic deployment

Release complete

Pipeline Flow

📝 Push

→

🔨 Build

→

🧪 Test

→

🚀 Deploy

Why is automation necessary?

Prevent human error: Eliminate mistakes from manual processes
Fast feedback: Catch problems immediately
Consistency: Deploy through the same process every time
Time savings: Free up time to focus on development

GitHub Actions Basics

GitHub Actions is a free CI/CD tool built into GitHub. You can use it directly from your code repository without a separate server.

Workflow File Location

Project structure

my-project/
├── .github/
│   └── workflows/
│       ├── ci.yml          # CI workflow
│       ├── deploy.yml      # Deployment workflow
│       └── test.yml        # Test workflow
├── src/
└── ...

YAML Syntax Essentials

.github/workflows/hello.yml

name: Hello World CI  # Workflow name

on:  # Trigger conditions
  push:
    branches: [main]
  pull_request:
    branches: [main]

jobs:  # Jobs to run
  build:
    runs-on: ubuntu-latest  # Execution environment

    steps:  # Steps to execute sequentially
      - name: Checkout code
        uses: actions/checkout@v4

      - name: Print Hello World
        run: echo "Hello, GitHub Actions!"

Trigger Types

Trigger	Description	Example
push	On code push	branches: [main]
pull_request	On PR creation/update	types: [opened, synchronize]
schedule	At scheduled times (cron)	cron: '0 0 * * *'
workflow_dispatch	Manual trigger	Click button in GitHub UI

Commonly Used Actions

actions/checkout@v4

Checkout repository code

actions/setup-node@v4

Set up Node.js environment

actions/setup-python@v5

Set up Python environment

actions/cache@v4

Dependency caching

Frontend Automated Deployment

Automatically deploy React/Vue projects to Cloudflare Pages.

Cloudflare Pages Deployment Workflow

.github/workflows/deploy-frontend.yml

name: Deploy Frontend

on:
  push:
    branches: [main]
    paths:
      - 'frontend/**'  # Only run when frontend folder changes

jobs:
  deploy:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Setup Node.js
        uses: actions/setup-node@v4
        with:
          node-version: '20'
          cache: 'npm'
          cache-dependency-path: frontend/package-lock.json

      - name: Install dependencies
        working-directory: frontend
        run: npm ci

      - name: Build
        working-directory: frontend
        run: npm run build
        env:
          VITE_API_URL: ${{ secrets.VITE_API_URL }}

      - name: Deploy to Cloudflare Pages
        uses: cloudflare/pages-action@v1
        with:
          apiToken: ${{ secrets.CLOUDFLARE_API_TOKEN }}
          accountId: ${{ secrets.CLOUDFLARE_ACCOUNT_ID }}
          projectName: my-frontend
          directory: frontend/dist

How to Set Up Secrets

GitHub repository → Settings → Secrets and variables → Actions
Click New repository secret
Name: CLOUDFLARE_API_TOKEN
Value: API token generated from Cloudflare dashboard

Creating a Cloudflare API Token

Cloudflare dashboard → My Profile → API Tokens
Create Token → Use the Edit Cloudflare Workers template
Account Resources: Select your account
Zone Resources: All zones (or a specific domain)

Backend Automated Deployment

Automatically deploy FastAPI/Node.js backends to Cloud Run.

FastAPI → Cloud Run Deployment

.github/workflows/deploy-backend.yml (FastAPI)

name: Deploy Backend (FastAPI)

on:
  push:
    branches: [main]
    paths:
      - 'backend/**'

env:
  PROJECT_ID: my-gcp-project
  REGION: asia-northeast3
  SERVICE_NAME: my-api

jobs:
  deploy:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Google Auth
        uses: google-github-actions/auth@v2
        with:
          credentials_json: ${{ secrets.GCP_SA_KEY }}

      - name: Setup Cloud SDK
        uses: google-github-actions/setup-gcloud@v2

      - name: Configure Docker
        run: gcloud auth configure-docker ${{ env.REGION }}-docker.pkg.dev

      - name: Build and Push Docker Image
        working-directory: backend
        run: |
          docker build -t ${{ env.REGION }}-docker.pkg.dev/${{ env.PROJECT_ID }}/my-repo/${{ env.SERVICE_NAME }}:${{ github.sha }} .
          docker push ${{ env.REGION }}-docker.pkg.dev/${{ env.PROJECT_ID }}/my-repo/${{ env.SERVICE_NAME }}:${{ github.sha }}

      - name: Deploy to Cloud Run
        run: |
          gcloud run deploy ${{ env.SERVICE_NAME }} \
            --image=${{ env.REGION }}-docker.pkg.dev/${{ env.PROJECT_ID }}/my-repo/${{ env.SERVICE_NAME }}:${{ github.sha }} \
            --region=${{ env.REGION }} \
            --platform=managed \
            --allow-unauthenticated \
            --set-env-vars="DATABASE_URL=${{ secrets.DATABASE_URL }}"

Node.js (Hono) → Cloud Run Deployment

.github/workflows/deploy-backend.yml (Hono)

name: Deploy Backend (Hono)

on:
  push:
    branches: [main]
    paths:
      - 'backend/**'

env:
  PROJECT_ID: my-gcp-project
  REGION: asia-northeast3
  SERVICE_NAME: my-api

jobs:
  deploy:
    runs-on: ubuntu-latest

    steps:
      - name: Checkout
        uses: actions/checkout@v4

      - name: Google Auth
        uses: google-github-actions/auth@v2
        with:
          credentials_json: ${{ secrets.GCP_SA_KEY }}

      - name: Setup Cloud SDK
        uses: google-github-actions/setup-gcloud@v2

      - name: Configure Docker
        run: gcloud auth configure-docker ${{ env.REGION }}-docker.pkg.dev

      - name: Build and Push Docker Image
        working-directory: backend
        run: |
          docker build -t ${{ env.REGION }}-docker.pkg.dev/${{ env.PROJECT_ID }}/my-repo/${{ env.SERVICE_NAME }}:${{ github.sha }} .
          docker push ${{ env.REGION }}-docker.pkg.dev/${{ env.PROJECT_ID }}/my-repo/${{ env.SERVICE_NAME }}:${{ github.sha }}

      - name: Deploy to Cloud Run
        run: |
          gcloud run deploy ${{ env.SERVICE_NAME }} \
            --image=${{ env.REGION }}-docker.pkg.dev/${{ env.PROJECT_ID }}/my-repo/${{ env.SERVICE_NAME }}:${{ github.sha }} \
            --region=${{ env.REGION }} \
            --platform=managed \
            --allow-unauthenticated

Creating GCP Service Account Key

Terminal

# 1. Create service account
gcloud iam service-accounts create github-actions \
  --display-name="GitHub Actions"

# 2. Grant required roles
gcloud projects add-iam-policy-binding PROJECT_ID \
  --member="serviceAccount:github-actions@PROJECT_ID.iam.gserviceaccount.com" \
  --role="roles/run.admin"

gcloud projects add-iam-policy-binding PROJECT_ID \
  --member="serviceAccount:github-actions@PROJECT_ID.iam.gserviceaccount.com" \
  --role="roles/storage.admin"

gcloud projects add-iam-policy-binding PROJECT_ID \
  --member="serviceAccount:github-actions@PROJECT_ID.iam.gserviceaccount.com" \
  --role="roles/iam.serviceAccountUser"

# 3. Generate key (JSON file)
gcloud iam service-accounts keys create key.json \
  --iam-account=github-actions@PROJECT_ID.iam.gserviceaccount.com

# 4. Register the contents of key.json as the GCP_SA_KEY secret

Environment-based Deployment (dev/staging/prod)

Environment-based deployment example

name: Deploy by Branch

on:
  push:
    branches:
      - main        # Production
      - staging     # Staging
      - develop     # Development

jobs:
  deploy:
    runs-on: ubuntu-latest

    steps:
      - name: Set environment
        run: |
          if [ "${{ github.ref }}" = "refs/heads/main" ]; then
            echo "ENV=prod" >> $GITHUB_ENV
            echo "SERVICE_NAME=my-api" >> $GITHUB_ENV
          elif [ "${{ github.ref }}" = "refs/heads/staging" ]; then
            echo "ENV=staging" >> $GITHUB_ENV
            echo "SERVICE_NAME=my-api-staging" >> $GITHUB_ENV
          else
            echo "ENV=dev" >> $GITHUB_ENV
            echo "SERVICE_NAME=my-api-dev" >> $GITHUB_ENV
          fi

      # ... Use ${{ env.SERVICE_NAME }} in subsequent deploy steps

Advanced Patterns

Matrix Build

Test across multiple versions/environments simultaneously.

Matrix Build

jobs:
  test:
    runs-on: ubuntu-latest
    strategy:
      matrix:
        node-version: [18, 20, 22]
        os: [ubuntu-latest, macos-latest]

    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-node@v4
        with:
          node-version: ${{ matrix.node-version }}
      - run: npm ci
      - run: npm test

Speed Up Builds with Caching

Caching examples

# Node.js dependency caching
- uses: actions/setup-node@v4
  with:
    node-version: '20'
    cache: 'npm'  # Automatic caching!

# Python dependency caching
- uses: actions/setup-python@v5
  with:
    python-version: '3.11'
    cache: 'pip'  # Automatic caching!

# Docker layer caching
- uses: docker/build-push-action@v5
  with:
    cache-from: type=gha
    cache-to: type=gha,mode=max

Conditional Execution

Conditional execution

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - name: Build
        run: npm run build

  deploy:
    needs: build  # Run after build completes
    if: github.ref == 'refs/heads/main'  # Only on main branch
    runs-on: ubuntu-latest
    steps:
      - name: Deploy
        run: echo "Deploying..."

Free Tier & Tips

GitHub Actions Free Limits

Plan	Free Allowance
Public repositories	Unlimited
Private (Free plan)	2,000 minutes/month
Private (Pro plan)	3,000 minutes/month

Cost Optimization Tips

Use caching: Reduce build time with dependency caching
Path filters: Only build changed folders (paths option)
Conditional execution: Skip unnecessary workflows
Self-hosted Runner: Use your own runner for heavy builds

Common Errors

❌ Permission denied

Service account is missing required roles

→ Add roles like roles/run.admin in IAM

❌ Secret not found

Referencing a variable not registered in Secrets

→ Add the variable in Settings → Secrets

❌ Docker build failed

Works locally but fails in CI

→ Check .dockerignore, verify environment variables

🎉 Learning Cycles Complete!

Congratulations! You've completed all learning cycles. You can now build the entire web service deployment pipeline from domain setup to automated deployment. Try starting a real project using Agent Recipes!

What is CI/CD?

CI (Continuous Integration)

CD (Continuous Deployment)

Pipeline Flow

GitHub Actions Basics

Workflow File Location

YAML Syntax Essentials

Trigger Types

Commonly Used Actions

actions/checkout@v4

actions/setup-node@v4

actions/setup-python@v5

actions/cache@v4

Frontend Automated Deployment

Cloudflare Pages Deployment Workflow

How to Set Up Secrets

Backend Automated Deployment

FastAPI → Cloud Run Deployment

Node.js (Hono) → Cloud Run Deployment

Creating GCP Service Account Key

Environment-based Deployment (dev/staging/prod)

Advanced Patterns

Matrix Build

Speed Up Builds with Caching

Conditional Execution

Free Tier & Tips

GitHub Actions Free Limits

Common Errors

❌ Permission denied

❌ Secret not found

❌ Docker build failed

Send Feedback