CI & CD pipelines- GitHub Actions, GitLab CI

Perfect — let’s go through CI/CD pipelines for Node.js, focusing on GitHub Actions and GitLab CI, which are essential for automated testing, building, and deployment.

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1️⃣ What is CI/CD?

• CI (Continuous Integration): Automatically builds and tests code on every commit

• CD (Continuous Deployment/Delivery): Automatically deploys code to staging or production after successful CI

• Benefits:

  • Early bug detection

  • Faster release cycles

  • Repeatable and consistent deployment

  • Reduces human error

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2️⃣ GitHub Actions

• Built into GitHub repositories

• Uses YAML workflows in .github/workflows/

• Can trigger on push, pull request, schedule, or manual events

a) Example Workflow: Node.js CI

# .github/workflows/nodejs.yml
name: Node.js CI
 
on:
  push:
    branches: [main]
  pull_request:
    branches: [main]
 
jobs:
  build:
    runs-on: ubuntu-latest
 
    steps:
      - name: Checkout code
        uses: actions/checkout@v3
 
      - name: Setup Node.js
        uses: actions/setup-node@v3
        with:
          node-version: 20
 
      - name: Install dependencies
        run: npm install
 
      - name: Run tests
        run: npm test
 
      - name: Build project
        run: npm run build

• Automatically runs install, test, and build on every push or PR

• Can add deployment step: AWS, Heroku, Vercel, Docker, etc.

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3️⃣ GitLab CI/CD

• Integrated CI/CD in GitLab repositories

• Uses .gitlab-ci.yml at project root

• Similar concepts: stages, jobs, runners

a) Example Workflow: Node.js CI

stages:
  - install
  - test
  - build
  - deploy
 
install:
  stage: install
  image: node:20
  script:
    - npm install
 
test:
  stage: test
  image: node:20
  script:
    - npm test
 
build:
  stage: build
  image: node:20
  script:
    - npm run build
 
deploy:
  stage: deploy
  image: node:20
  script:
    - echo "Deploying to production..."
  only:
    - main

• Each job runs in isolated environment (runner)

• Can add artifacts, caching, notifications

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4️⃣ Key Concepts

1. Stages: Define phases (install, test, build, deploy)

2. Jobs: Individual tasks within stages

3. Runners / Agents: Machines executing the jobs

4. Triggers: Events that start the pipeline (push, merge request, schedule)

5. Artifacts: Files produced in one job and passed to next job

6. Caching: Speeds up pipelines (e.g., node_modules)

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5️⃣ Benefits for Node.js Projects

• Automatically run unit, integration, and linting tests

• Prevents broken code from being deployed

• Enables continuous deployment to staging/production

• Integrates with Docker, Kubernetes, serverless, or PaaS

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6️⃣ Key Takeaways

Feature	GitHub Actions	GitLab CI/CD
Integration	GitHub native	GitLab native
Config file	.github/workflows/*.yml	.gitlab-ci.yml
Runners	GitHub-hosted or self-hosted	GitLab-hosted or self-hosted
Trigger events	Push, PR, schedule, manual	Push, MR, schedule, manual
Use Case	CI/CD pipelines, deployment	CI/CD pipelines, deployment

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Next, we could go through Node.js production best practices, combining performance, monitoring, logging, security, clustering, and deployment strategies for real-world applications.

Do you want me to go there next?