Docker-Compose.yaml

services:
  # SETUP INSTRUCTIONS (FOR WINDOWS AND MAC)
  # 1. Create the required folders for mounting the volumes if they do not exist
  #   (refer to the volumes section at the end of this file)
  # 2. Go to "Docker Desktop → Settings → Resources → File Sharing" → Add the project’s root folder.

  apache-php:
    image: customized-apache-httpd-plus-php:1.0
    build:
      context: ./images/apache-httpd-plus-php
      dockerfile: Dockerfile
    hostname: apache-2.4-php-8.2
    container_name: apache-2.4-php-8.2
    restart: always
    ports:
      - 8002:80
    volumes:
      # To store the web-related files in a persistent volume (directory/folder) in the host
      - apache-httpd-www:/var/www/html/
      # To store the PHP configuration file in the host
      - php-config:/usr/local/etc/php/
    environment:
      PHP_DISPLAY_ERRORS: 1
      PHP_DISPLAY_STARTUP_ERRORS: 1
    command: >
      /bin/bash -c "
      apache2-foreground
      "

  mysql-8.0.40-debian:
    image: customized-mysql:1.0
    build:
      context: ./images/mysql
      dockerfile: Dockerfile
    hostname: mysql-8.0.40-debian
    container_name: mysql-8.0.40-debian
    restart: no
    ports:
      - 3307:3306
    environment:
      MYSQL_ROOT_PASSWORD: 5trathm0re
    volumes:
      # To store the server's configuration file in the host
      - mysql-config:/etc/mysql/
      # To store the server's log files in the host
      - mysql-log:/var/log/mysql/
      # To store the server's data persistently in the host
      - mysql-data:/var/lib/mysql/
      # To run the SQL scripts used to create the required databases
      - mysql-init:/docker-entrypoint-initdb.d/
    command: >
      /bin/bash -c "
      chmod 644 /etc/mysql/my.cnf &&
      chmod 644 /etc/mysql/conf.d/docker.cnf &&
      chmod 644 /etc/mysql/conf.d/mysql.cnf &&
      exec docker-entrypoint.sh mysqld
      "

  postgres-17.2:
    image: postgres:17.2
    hostname: postgres-17.2
    container_name: postgres-17.2
    restart: always
    shm_size: 1g
    ports:
      - 5433:5432
    environment:
      POSTGRES_USER: postgres
      POSTGRES_PASSWORD: 5trathm0re
      PGDATA: /var/lib/postgresql/data/pgdata
    volumes:
      # To store the server's configuration files (postgresql.conf and pg_hba.conf) in the host
      - postgres-config:/etc/postgresql/
      # To store the server's log files in the host
      - postgres-log:/var/log/postgresql/
      # To store the server's data persistently in the host
      - postgres-data:/var/lib/postgresql/data
      # To run the SQL scripts used to create the required databases
      - postgres-init:/docker-entrypoint-initdb.d/
    command: postgres -c 'config_file=/etc/postgresql/postgresql.conf'

  mysql_backup:
    image: customized-mysql:1.0
    build:
      context: ./images/mysql
      dockerfile: Dockerfile
    hostname: mysql_backup
    container_name: mysql_backup
    # restart: no → The default. The container runs once. If it stops, then it stays stopped.
    # restart: always → The container always runs, even after the host machine restarts.
    # restart: on-failure → The container restarts only if it exists with a non-zero exit code.
    # restart: on-failure:5 → The container restarts only if it exists with a non-zero exit code, but it is restarted up to a maximum of 5 times in a row.
    # restart: unless-stopped → The container always restarts unless it is manually stopped.
    restart: unless-stopped
    depends_on:
      - mysql-8.0.40-debian
    volumes:
      # To store the server's backups persistently in the host
      - mysql-backup:/backup/mysql/
      # Secret file containing the credentials to access the MySQL server
      - mysql-secrets:/root/
      # `sleep 30` (30 seconds) provides a startup delay to give the MySQL server time to start
      # before the first backup is initiated.

      # `sleep 10800` (3 hours) provides a periodic backup interval that repeats forever,
      # as long as the container is running.
      # ----------- We can change this to `sleep 120` for teaching purposes, i.e., perform the backups every 2 minutes.

      # Retention Policy for the Backups (to avoid filling up the storage space):
      # Best Practice: Retention policies should be enforced by the storage layer, not in a shell loop inside the container.

      # `find /backup/mysql -type f -name '*.sql' -mtime +7 -print -delete >> $$LOG_FILE 2>&1;`
      # ----------- We can change this to `find /backup/mysql -type f -name '*.sql' -mmin +2 -print -delete >> $$LOG_FILE 2>&1;` for files older than 2 minutes.
        # -mtime +7 → finds files older than 7 days (assuming that you will not take more than 7 days to notice corrupted databases).
        # -type f → finds only files, not directories.
        # -name '*.sql' → only database dumps.
        # -delete → simple, permanent deletion without any confirmation.
        # -print → prints the names of the files that would be deleted (basic logging).
        # $$LOG_FILE 2>&1; → Take errors and send them to the same place as the normal output.
    command: >
      /bin/bash -c "
      LOG_FILE=/backup/mysql/backup.log;
    
      touch $$LOG_FILE &&
      chmod 600 /root/.my.cnf &&
      sleep 30 &&
    
      while true; do
        echo \"[$(date '+%Y-%m-%d %H:%M:%S')] Backup started\" >> $$LOG_FILE;
    
        if mysqldump --all-databases --single-transaction --quick --lock-tables=false > /backup/mysql/full_dump_$(date +%Y%m%d_%H%M).sql; then
    
          echo \"[$(date '+%Y-%m-%d %H:%M:%S')] Backup completed successfully\" >> $$LOG_FILE;
    
          find /backup/mysql -type f -name '*.sql' -mtime +7 -print -delete >> $$LOG_FILE 2>&1;
    
          echo \"[$(date '+%Y-%m-%d %H:%M:%S')] Backup retention policy enforced\" >> $$LOG_FILE;
    
        else
          echo \"[$(date '+%Y-%m-%d %H:%M:%S')] ERROR: Backup failed\" >> $$LOG_FILE;
        fi
    
        sleep 10800;
      done
      "

volumes:
  # MySQL volumes
  mysql-config:
    driver: local # The volume will be stored locally on the host machine
    driver_opts:
      type: none # Binds to the path specified in "device" instead of creating a new directory/file on the host
      o: bind # Confirms that Docker maps a directory/file on the host directly into the container
      device: ./container-volumes/mysql/etc-mysql/
  mysql-log:
    driver: local
    driver_opts:
      type: none
      o: bind
      device: ./container-volumes/mysql/var-log-mysql/
  mysql-data:
    driver: local
    driver_opts:
      type: none
      o: bind
      device: ./container-volumes/mysql/var-lib-mysql/
  mysql-init:
    driver: local
    driver_opts:
      type: none
      o: bind
      device: ./container-volumes/mysql/init-scripts/
  mysql-backup:
    driver: local
    driver_opts:
      type: none
      o: bind
      device: ./container-volumes/backup/mysql/
  mysql-secrets:
    driver: local
    driver_opts:
      type: none
      o: bind
      device: ./container-volumes/docker-secrets/mysql/

  # PostgreSQL volumes
  postgres-config:
    driver: local
    driver_opts:
      type: none
      o: bind
      device: ./container-volumes/postgresql/etc-postgresql/
  postgres-log:
    driver: local
    driver_opts:
      type: none
      o: bind
      device: ./container-volumes/postgresql/var-log-postgresql/
  postgres-data:
    driver: local
    driver_opts:
      type: none
      o: bind
      device: ./container-volumes/postgresql/var-lib-postgresql-data/
  postgres-init:
    driver: local
    driver_opts:
      type: none
      o: bind
      device: ./container-volumes/postgresql/init-scripts/

  # Apache volumes
  apache-httpd-www:
    driver: local
    driver_opts:
      type: none
      o: bind
      device: ./container-volumes/apache/var-www-html/
  php-config:
    driver: local
    driver_opts:
      type: none
      o: bind
      device: ./container-volumes/apache/etc-php/