How fix the error Exception when execute yii migrate?

Question

I try to run a yii2 basic project with docker in ubuntu 18.04. This is my docker-compose.yml:

version: '2'
services:
  php:
    image: yiisoftware/yii2-php:7.1-apache
    volumes:
      - ~/projects/basic/.composer-docker/cache:/root/.composer/cache:delegated
      - ./:/app:delegated
    ports:
      - 8000:80
    links:
      - mysql

  mysql:
   image: mysql:5.7
   volumes:
      - ~/projects/basic/.composer-docker/mysql:/var/lib/mysql
   environment:
      - "MYSQL_ROOT_PASSWORD=secret"
      - "MYSQL_USER=app"
      - "MYSQL_PASSWORD=secret"
      - "MYSQL_DATABASE=app"
   ports:
    - '33061:3306' 

  phpmyadmin:
    image: phpmyadmin/phpmyadmin
    container_name: phpmyadmin
    restart: always
    environment:
      PMA_HOST: mysql
      MYSQL_USERNAME: app
      MYSQL_ROOT_PASSWORD: secret
  ports:
    - 8080:80
  volumes:
    - /sessions
  links:
    - 'mysql:mysql'

and this is config/db.php:

return [
'class' => 'yii\db\Connection',
'dsn' => 'mysql:host=127.0.0.1;dbname=app',
'username' => 'app',
'password' => 'secret',
'charset' => 'utf8',

I use the same folder console/migrations like in the yii2 advanced. When I run command ./yii migrate, the error "Exception 'yii\db\Exception' with message 'SQLSTATE[HY000] [2002] Connection refused'" is occured. In the another case when host=mysql I get error "Exception 'yii\db\Exception' with message 'SQLSTATE[HY000] [2002] php_network_getaddresses: getaddrinfo failed: Name or service not known'". What I did wrong?

Answer 1

while using docker-compose your host would be referred by the name of the service. so you would have the host=mysql in your case, not host=127.0.0.1.

If you run docker-compose different services are like different hosts. You run the web app in your php (service name) app which connects to the database service to the mysql (service name) app