Building docker compose and getting error with mariadb and phpmyadmin

Docker Engine Compose
1

I’ve just started using Docker and Docker composer and I’m trying to set up a localhost development system. Currently, I’m using Phpstorm 2024 and Vs Code.

My problem is: I’m trying to build the stack “php:8.4.2-apache (which works) and mariadb and phpmyadmin (which I get connection errors)”

When I log into phpmyadmin I get this message
"Welcome to phpMyAdmin

Error
MySQL Message: Documentation

Cannot connect: invalid settings.
mysqli::real_connect(): (HY000/1045): Access denied for user ‘user’@‘172.18.0.4’ (using password: YES)
phpMyAdmin tried to connect to the MySQL server and the connection was refused. You should check the server, username and password in config.inc.php and make sure they match the information provided by the MySQL server administrator."

MY docker composer


version: "3.8"

services:
  php:
    image: php:8.4-apache # Considere atualizar para uma versão mais recente
    container_name: php
    volumes:
      - ./src:/var/www/html
      - ./php.ini:/usr/local/etc/php/php.ini
    ports:
      - "8080:80"
    networks:
      - backend
    depends_on:
      - mariadb

  mariadb:
    image: mariadb:latest
    container_name: mariadb
    restart: always
    environment:
      MARIADB_ROOT_PASSWORD: 123456
      MARIADB_DATABASE: default_database
      MARIADB_USER: user
      MARIADB_PASSWORD: user
    volumes:
      - mariadb_data:/var/lib/mysql
    networks:
      - backend

  phpmyadmin:
    image: phpmyadmin/phpmyadmin:latest
    container_name: phpmyadmin
    restart: always
    environment:
      PMA_HOST: mariadb # Usa o nome do serviço para resolução interna
      PMA_USER: user
      PMA_PASSWORD: user
    ports:
      - "8181:80"
    networks:
      - backend
    depends_on:
      - mariadb

volumes:
  mariadb_data:

networks:
  backend:
2

The mariadb entrypoint skript creates the user the first time the database is started. If you change the password in the compose file after the first creation, it will not update it in the database.

If you can afford to lose the data, execute docker compose down -v to get rid of the volume and start with a clean state. Then deploy the compose project again with docker compose up and it should work.