Minimal docker-compose for MySQL 8.4.3

Question

The example from the official WordPress Docker image page (actual for the end of 2024):

services:

  wordpress:
    image: wordpress
    restart: always
    ports:
      - 8080:80
    environment:
      WORDPRESS_DB_HOST: db
      WORDPRESS_DB_USER: exampleuser
      WORDPRESS_DB_PASSWORD: examplepass
      WORDPRESS_DB_NAME: exampledb
    volumes:
      - wordpress:/var/www/html

  db:
    image: mysql:8.0
    restart: always
    environment:
      MYSQL_DATABASE: exampledb
      MYSQL_USER: exampleuser
      MYSQL_PASSWORD: examplepass
      MYSQL_RANDOM_ROOT_PASSWORD: '1'
    volumes:
      - db:/var/lib/mysql

volumes:
  wordpress:
  db:

My preset is close to this one:

services:

  WordPress:

    container_name: Example-WordPressHomePage-WordPress
    image: wordpress:6.7.1-php8.1-apache
    ports:
      - 80:80

    volumes:
      - ./wordpress:/var/www/html

    restart: always
    environment:
      - WORDPRESS_DB_HOST=db
      - WORDPRESS_DB_USER=wordpress
      - WORDPRESS_DB_PASSWORD=wordpress
      - WORDPRESS_DB_NAME=wordpress

  Database:

    container_name: Example-WordPressHomePage-Database
    image: mysql:8.4.3
    volumes:
      - ./database:/var/lib/mysql

    restart: always
    environment:
      - MYSQL_ROOT_PASSWORD=somewordpress
      - MYSQL_DATABASE=wordpress
      - MYSQL_USER=wordpress
      - MYSQL_PASSWORD=wordpress

    expose:
      - 3306
      - 33060

Currently, the WordPress cannot connect with the database:

However, the direct connection via IntelliJ IDEA tools does not work too:

I suppose, the above preset is not enough for mysql:8.4.3 image. What else must be done?

Answer 1

In Compose, you use the service names as hostnames. You've renamed db to Database, so you also have to use WORDPRESS_DB_HOST=Database.

I'll recommend that you use lowercase names as Linux is case sensitive and you'll get less errors if you just use lowercase all the time.

The reason you can't connect from IntelliJ is that you don't map a host port to the MySQL container. expose doesn't do that. You need to map port 3306 with the ports directive like it's done on the Wordpress container if you want to be able to access it from outside the Docker network.

Something like this should work better

  WordPress:

    container_name: Example-WordPressHomePage-WordPress
    image: wordpress:6.7.1-php8.1-apache
    ports:
      - 80:80

    volumes:
      - ./wordpress:/var/www/html

    restart: always
    environment:
      - WORDPRESS_DB_HOST=Database
      - WORDPRESS_DB_USER=wordpress
      - WORDPRESS_DB_PASSWORD=wordpress
      - WORDPRESS_DB_NAME=wordpress

  Database:

    container_name: Example-WordPressHomePage-Database
    image: mysql:8.4.3
    volumes:
      - ./database:/var/lib/mysql

    restart: always
    environment:
      - MYSQL_ROOT_PASSWORD=somewordpress
      - MYSQL_DATABASE=wordpress
      - MYSQL_USER=wordpress
      - MYSQL_PASSWORD=wordpress

    ports:
      - 3306:3306