GitHub Actions中MySQL数据库访问失败及启动异常求助

• 确认action参数配置无遗漏，核心必填参数要准确传递：

  - name: Setup MySQL
    uses: mirromutth/mysql-action@v1.1
    with:
      host port: 3306  # 可自定义端口，比如3307
      mysql version: '8.0'
      mysql database: your_test_db
      mysql root password: ${{ secrets.MYSQL_ROOT_PWD }}
      mysql user: test_user
      mysql password: ${{ secrets.MYSQL_USER_PWD }}
  

• 连接MySQL时必须用127.0.0.1而非localhost，容器内MySQL的socket文件和主机不共享，localhost会尝试走socket连接导致失败：

  mysql -h 127.0.0.1 -P 3306 -u root -p${{ secrets.MYSQL_ROOT_PWD }}
  

• 检查GitHub Secrets配置：在仓库Settings->Secrets and variables->Actions里确认密码无多余空格，引用时不要加引号。

• 完全不需要执行sudo systemctl start mysql.service，mirromutth/mysql-action是通过Docker容器运行MySQL的，主机上默认没有安装/启动MySQL服务，执行该命令本身就是错误操作。
• 如果主机上之前装过MySQL，3306端口可能被占用导致容器无法启动，可二选一操作：
  • 换用非默认端口（比如3307）在action的host port参数指定；
  • 在action之前先停止主机上的MySQL服务：

    sudo systemctl stop mysql.service || true
    sudo systemctl disable mysql.service || true
    

name: Test & Deploy
on: [push, pull_request]

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout code
        uses: actions/checkout@v4

      - name: Stop host MySQL if exists
        run: |
          sudo systemctl stop mysql.service || true
          sudo systemctl disable mysql.service || true

      - name: Setup MySQL
        uses: mirromutth/mysql-action@v1.1
        with:
          host port: 3306
          mysql version: '8.0'
          mysql database: test_db
          mysql root password: ${{ secrets.MYSQL_ROOT_PWD }}
          mysql user: app_user
          mysql password: ${{ secrets.MYSQL_USER_PWD }}

      - name: Wait for MySQL ready
        run: |
          until mysqladmin ping -h 127.0.0.1 -P 3306 -u root -p${{ secrets.MYSQL_ROOT_PWD }} --silent; do
            echo "Waiting for MySQL..."
            sleep 2
          done

      - name: Execute setup script
        run: mysql -h 127.0.0.1 -P 3306 -u root -p${{ secrets.MYSQL_ROOT_PWD }} < setup_mysql_test.sql

      - name: Install Python dependencies
        run: pip install -r requirements.txt

      - name: Run tests
        run: pytest tests/
        env:
          DB_HOST: 127.0.0.1
          DB_PORT: 3306
          DB_USER: app_user
          DB_PASSWORD: ${{ secrets.MYSQL_USER_PWD }}
          DB_NAME: test_db

• MySQL 8.0默认使用caching_sha2_password认证插件，若你的Python客户端版本较老，需在setup_mysql_test.sql里修改用户认证方式：

  ALTER USER 'app_user'@'%' IDENTIFIED WITH mysql_native_password BY 'your_user_password';
  FLUSH PRIVILEGES;
  

• 确保setup_mysql_test.sql里的用户权限允许从任意主机连接：

  GRANT ALL PRIVILEGES ON test_db.* TO 'app_user'@'%';
  FLUSH PRIVILEGES;
  

内容的提问来源于stack exchange，提问作者reinhard