docker-compose.yml

services:
  backend:
    build:
      context: ./backend # Specify the backend directory for the Docker build context.
    # environment:
    #   - PORT=5001
    #   - DB_HOST=db
    #   - DB_USER=postgres
    #   - DB_PASSWORD=postgres
    #   - DB_NAME=flightdb
    #   - DB_PORT=5432
    environment:
      - PORT=${PORT}         # Port on which the backend server will run.
      - DB_HOST=${DB_HOST}   # Hostname for the database container.
      - DB_USER=${DB_USER}   # Database username.
      - DB_PASSWORD=${DB_PASSWORD}  # Database password.
      - DB_NAME=${DB_NAME}   # Name of the database to connect to.
      - DB_PORT=${DB_PORT}   # Port number for the database.
    ports:
      - "5001:5001"         # Map port 5001 of the container to port 5001 on the host machine.
    depends_on:
      db:
        condition: service_healthy  # Wait for the database container to be healthy before starting.

  db:
    image: postgres:13
    environment:
      POSTGRES_USER: postgres       # Set the default database username.
      POSTGRES_PASSWORD: postgres   # Set the default database password.
      POSTGRES_DB: flightdb         # Create a database named "flightdb".
    volumes:
      - pgdata:/var/lib/postgresql/data                     # Persistent storage for database data.
      - ./db/init.sql:/docker-entrypoint-initdb.d/init.sql  # Initialize the database with this SQL script.
    ports:
      - "5434:5432"                 # Map port 5432 of the container to port 5434 on the host machine.
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U postgres"] # Check if the database is ready to accept connections.
      interval: 5s
      timeout: 5s
      retries: 5

  frontend:
    build:
      context: ./frontend 
    ports:
      - "3000:3000"
    environment:
      - REACT_APP_BACKEND_URL=http://localhost:5001  # URL for the frontend to reach the backend

volumes:
  pgdata:   # Persistent volume for PostgreSQL data.