Docker Compose

Detect project type (Python/Node/Go) and framework:

# Python detection
ls requirements.txt pyproject.toml Pipfile setup.py 2>/dev/null

# Node detection
ls package.json 2>/dev/null

# Go detection
ls go.mod 2>/dev/null

/docker add <service> -- Add a service

1. Read the existing docker-compose.yml to understand current services, networks, and volumes.

2. Add the appropriate service block based on the requested service name:

   • postgres: PostgreSQL with health check, persistent volume, and environment variables

     postgres:
       image: postgres:16-alpine
       environment:
         POSTGRES_DB: app_db
         POSTGRES_USER: app_user
         POSTGRES_PASSWORD: ${POSTGRES_PASSWORD:-changeme}
       volumes:
         - postgres_data:/var/lib/postgresql/data
       healthcheck:
         test: ["CMD-SHELL", "pg_isready -U app_user -d app_db"]
         interval: 10s
         timeout: 5s
         retries: 5
     

   • redis: Redis with persistence and health check

     redis:
       image: redis:7-alpine
       command: redis-server --appendonly yes
       volumes:
         - redis_data:/data
       healthcheck:
         test: ["CMD", "redis-cli", "ping"]
         interval: 10s
         timeout: 5s
         retries: 5
     

   • celery: Celery worker using the same image as the app service, depends_on app

     celery:
       build: .
       command: celery -A app worker --loglevel=info
       depends_on:
         - app
         - redis
       env_file:
         - .env
     

   • celery-beat: Celery beat scheduler

     celery-beat:
       build: .
       command: celery -A app beat --loglevel=info
       depends_on:
         - celery
       env_file:
         - .env
     

   • nginx: Nginx reverse proxy with configuration volume

     nginx:
       image: nginx:alpine
       ports:
         - "80:80"
       volumes:
         - ./nginx.conf:/etc/nginx/conf.d/default.conf
       depends_on:
         - app
     

   • mailhog: Development email catcher

     mailhog:
       image: mailhog/mailhog
       ports:
         - "1025:1025"
         - "8025:8025"
     

3. Add necessary networks, volumes, and depends_on relationships to wire the new service into the existing compose graph.

4. Update the app service environment to reference the new service (e.g., add DATABASE_URL, REDIS_URL, or CELERY_BROKER_URL).

5. Present the updated compose file for review.

/docker optimize -- Check for anti-patterns

1. Read the Dockerfile and docker-compose.yml from the project root.

2. Check for common issues:

   Check	Severity	What to look for
   Running as root	High	No USER directive in Dockerfile
   No .dockerignore	Medium	Missing file or missing key entries (.git, node_modules, .env)
   COPY before deps	Medium	Source copied before dependency install, breaking layer cache
   Using latest tag	Medium	Base image uses :latest instead of a pinned version
   No health checks	Medium	No HEALTHCHECK in Dockerfile or healthcheck in compose
   Bloated final image	Low	Build tools (gcc, make) present in production stage
   Secrets in env/args	High	Passwords or tokens in ENV or ARG directives
   No multi-stage build	Low	Single FROM with both build and runtime dependencies

3. Present findings with severity level and a concrete fix suggestion for each issue:

   [HIGH] Running as root
     -> Add USER directive: RUN useradd -m appuser && USER appuser
   
   [MEDIUM] Using latest tag for base image
     -> Pin version: python:3.12-slim instead of python:latest
   

4. Offer to apply fixes automatically where possible (adding USER, reordering COPY, pinning tags).

Troubleshooting