Symfony4 / Docker：SQLSTATE [HY000] [2002]连接被拒绝

Question

我有Symfony 4和数据库连接的问题。我尝试使用php bin/console make:migration进行迁移，但后来我面临连接拒绝错误。

In AbstractmysqlDriver.php line 113:

  An exception occurred in driver: SQLSTATE[HY000] [2002] Connection refused  


In PDOConnection.php line 50:

  SQLSTATE[HY000] [2002] Connection refused  


In PDOConnection.php line 46:

  SQLSTATE[HY000] [2002] Connection refused

我的.env文件是这样的。

###> doctrine/doctrine-bundle ###
# Format described at http://docs.doctrine-project.org/projects/doctrine-dbal/en/latest/reference/configuration.html#connecting-using-a-url
# For an SQLite database, use: "sqlite:///%kernel.project_dir%/var/data.db"
# Configure your db driver and server_version in config/packages/doctrine.yaml
DATABASE_URL=mysql://db_user:db_password@127.0.0.1:3306/db_name
DATABASE_USER=sf4user
DATABASE_PWD=sf4pwd
DATABASE_NAME=sf4
DATABASE_HOST=127.0.0.1
DATABASE_PORT=3306
###< doctrine/doctrine-bundle ###

这是我的packages / doctrine.yaml：

parameters:
    # Adds a fallback DATABASE_URL if the env var is not set.
    # This allows you to run cache:warmup even if your
    # environment variables are not available yet.
    # You should not need to change this value.
    env(DATABASE_URL): ''

    doctrine:
        dbal:
            # configure these for your database server
            driver: 'pdo_mysql'
            server_version: '5.7'
            charset: utf8mb4
            default_table_options:
                charset: utf8mb4
                collate: utf8mb4_unicode_ci

            host: '%env(DATABASE_HOST)%'
            user: '%env(DATABASE_USER)%'
            password: '%env(DATABASE_PWD)%'
            dbname: '%env(DATABASE_NAME)%'
            port: '%env(DATABASE_PORT)%'

            url: '%env(resolve:DATABASE_URL)%'
        orm:
            auto_generate_proxy_classes: '%kernel.debug%'
            naming_strategy: doctrine.orm.naming_strategy.underscore
            auto_mapping: true
            mappings:
                App:
                    is_bundle: false
                    type: annotation
                    dir: '%kernel.project_dir%/src/Entity'
                    prefix: 'AppEntity'
                    alias: App

我明白数据库URL是基于我在.env文件中设置的那样解决的，但我无法使其工作，每当我尝试调用处理db的控制台方法时，我都会得到连接拒绝错误。

我使用docker-compose.yml文件构建项目：

version: '3'
services:
    apache:
        build: .docker/apache
        container_name: sf4_apache
        ports:
          - 80:80
        volumes:
          - .docker/config/vhosts:/etc/apache2/sites-enabled
          - .:/home/wwwroot/sf4
        depends_on:
          - php

    mysql:
        image: mysql
        container_name: sf4_mysql
        volumes:
            - .docker/data/db:/var/lib/mysql
        command: ["--default-authentication-plugin=mysql_native_password"]
        ports:
            - "3306:3306"
        environment:
            MYSQL_ROOT_PASSWORD: root_pwd_test
            MYSQL_DATABASE: sf4
            MYSQL_USER: sf4user
            MYSQL_PASSWORD: sf4pwd

    php:
        build: .docker/php
        container_name: sf4_php
        volumes:
          - .:/home/wwwroot/sf4
        environment:
          - maildev_host=sf4_maildev
        depends_on:
          - maildev
          - mysql

    phpmyadmin:
        image: phpmyadmin/phpmyadmin
        container_name: sf4_phpmyadmin
        ports:
            - 8080:80
        links:
            - mysql
        environment:
            MYSQL_USERNAME: root
            MYSQL_ROOT_PASSWORD: root_pwd_test
            PMA_HOST: mysql

我能错过什么？