Dockerize node

1. create a Dockerfile for node

   FROM node:20-alpine
   # 1) Create non-root user# addgroup --system appgroup: Creates a system group named appgroup.# adduser --system --ingroup appgroup appuser: Creates a system user named appuser and adds it to appgroup.# USER appuser: Tells Docker to run all subsequent commands (including your app) as appuser instead of root.RUN addgroup -S appgroup && adduser -S -G appgroup appuser
   # 2) Set working directoryWORKDIR /app
   # Fix: Set ownership of /app to app userRUN chown app:app /app
   # 3) Copy only manifest files first (better layer caching)COPY --chown=app:app package*.json ./
   # 4) Install deps (prod only for production images)USER app
   RUN npm ci --omit=dev
   # 5) Copy the rest of the appCOPY --chown=app:app . .
   # 6) Runtime configENV NODE_ENV=production
   EXPOSE 8000
   CMD ["npm", "start"]

2. Create a .dockerignore

   node_modules
   npm-debug.log
   .git
   .gitignore
   Dockerfile
   .dockerignore
   .env
   dist
   coverage
   .vscode
   

3. Build the image

   docker build -t blogapi:latest .

4. Run Container with .env

   docker run -d --restart unless-stopped --name blogapi --env-file .env -p 8000:8000 blogapi:latest

5. Inspect and interact

• Logs (follow): docker logs -f web-app
• Stop / remove: docker stop web-app docker rm web-app

6. Optional: Dev mode (hot reload)

7. Publihs image

• docker login
• docker tag blogapi:latest <your-username>/blogapi:latest
• docker push <your-username>/blogapi:latest