docker-compose.prod.yml

# Production Docker Configuration for CodeIgniter 4 Application
# =============================================================
#
# This Docker Compose configuration is designed for production deployment of a
# CodeIgniter 4 application. It defines four main services: the application itself (`app`),
# an Nginx web server (`nginx`), a MySQL database (`mysql`), and a Redis cache (`redis`).
# Each service is configured with production in mind, using Alpine images where available
# for their smaller footprint and setting environment variables for secure and efficient operation.
#
# Usage:
# ------
# Before running, ensure you have set the environment variables `MYSQL_PROD_DATABASE`,
# `MYSQL_PROD_USER`, and `MYSQL_PROD_PASSWORD` for the MySQL service. These can be set
# in an `.env` file located in the same directory as this docker-compose file or exported
# directly in your shell.
#
# To start all services in detached mode, use:
# `docker-compose -f docker-compose.prod.yml up -d`
#
# To stop all services and remove containers, networks, and volumes created by `up`, use:
# `docker-compose -f docker-compose.prod.yml down`
#
# Services:
# ---------
# app: The main application service built from a Dockerfile located in `./docker/ci4`.
#      It's configured to run in a `production` environment. The entire application directory
#      is mounted into the container to facilitate easy updates, but consider using COPY
#      in Dockerfile for a more secure, immutable deployment.
#
# nginx: Serves as the web server, using the lightweight Alpine Linux version of Nginx.
#        It serves static files directly and proxies PHP requests to the `app` service.
#        The production Nginx configuration is mounted from `./docker/nginx/nginx.prod.conf`.
#
# mysql: The MySQL database service, crucial for data persistence. It's configured through
#        environment variables for the database name, user, and password, which should be
#        securely managed. Data is persisted in a Docker volume named `mysql-data`.
#
# redis: Used for caching and session storage to enhance application performance.
#        Like Nginx, it uses an Alpine Linux image for a smaller footprint.
#
# Networks:
# ---------
# app-network: A custom bridge network that facilitates communication between services.
#              All services are attached to this network.
#
# Volumes:
# --------
# mysql-data: A Docker-managed volume that ensures the persistence of MySQL data across
#             container restarts and deployments.
#
# Notes:
# ------
# - This configuration is optimized for production use, but security and performance
#   tuning is an ongoing process. Always keep your images up to date and monitor
#   for any potential security vulnerabilities.
# - Ensure SSL/TLS configuration for Nginx if exposing services directly to the internet.
#   Consider using a service like Let's Encrypt for free SSL certificates.
#
version: '3.8'
services:
  app:
    build:
      context: ./docker/ci4
    volumes:
      - .:/var/www/html
    environment:
      CI_ENVIRONMENT: production
    networks:
      - app-network

  nginx:
    image: nginx:alpine # Using the alpine version for smaller size
    volumes:
      - ./public:/var/www/html/public
      - ./docker/nginx/nginx.prod.conf:/etc/nginx/conf.d/default.conf
    networks:
      - app-network
    depends_on:
      - app

  mysql:
    image: mysql:5.7
    environment:
      MYSQL_DATABASE: ${MYSQL_PROD_DATABASE}
      MYSQL_USER: ${MYSQL_PROD_USER}
      MYSQL_PASSWORD: ${MYSQL_PROD_PASSWORD}
    networks:
      - app-network

  redis:
    image: redis:alpine # Using the alpine version for smaller size
    networks:
      - app-network

networks:
  app-network:
    driver: bridge

volumes:
  mysql-data: