Question

我创建了一个带有mysql数据库的容器，并且与.net应用程序的手动连接非常有效。现在，我将使用docker-compose自动构建mysql容器和.net应用程序映像。

我的docker组成看起来像这样。

version: '3.1'

networks:
  overlay:
services:
  authentication_service:
    image: authentication_service:latest
    depends_on:
      - "authentication_service_db"
      - "adminer"
    build:
      context: .
      dockerfile: Dockerfile
    links:
      - authentication_service_db
    ports:
      - "5003:80"
    networks:
      - overlay
  authentication_service_db:
    image: mysql:8.0.3
    environment:
      MYSQL_ROOT_PASSWORD: secret
      MYSQL_DATABASE: authenticationdb
    ports:
      - 3305:3306
    restart: always
    volumes:
      - ./data-authentication:/var/lib/mysql
    networks:
      - overlay

当我在开发中启动应用程序时，将打印连接字符串，其外观类似于server=localhost;Port=3305;Database=authenticationdb;Uid=root;Pwd=secret。这行得通。

当我运行docker-compose up -d --build时，它会更改： server=authentication_service_db;Port=3305;Database=authenticationdb;Uid=root;Pwd=secret;

我的连接测试脚本：

private static void WaitForDbInit(string connectionString)
        {
            var connection = new MySqlConnection(connectionString);
            Console.WriteLine("Connecting with credentials: {0}", connectionString);

            var retries = 1;
            while (retries < 5)
            {
                try
                {
                    Console.WriteLine("Connecting to db. Trial: {0}", retries);
                    connection.Open();
                    connection.Close();
                    break;
                }
                catch (MySqlException)
                {
                    Thread.Sleep((int) Math.Pow(2, retries) * 1000);
                    retries++;
                }
            }
        }

日志：

Connecting to db. Trial: 1
Connecting to db. Trial: 2
Connecting to db. Trial: 3
Connecting to db. Trial: 4
[...]
application startup exception: MySql.Data.MySqlClient.MySqlException (0x80004005): Unable to connect to any of the specified MySQL hosts.
   at MySqlConnector.Core.ServerSession.ConnectAsync(ConnectionSettings cs, ILoadBalancer loadBalancer, IOBehavior ioBehavior, CancellationToken cancellationToken) in C:\projects\mysqlconnector\src\MySqlConnector\Core\ServerSession.cs:line 299

appsettings.json：

{
  "Logging": {
    "LogLevel": {
      "Default": "Warning"
    }
  },
  "AllowedHosts": "*",
  "MysqlConnection": {
    "connectionString": "server=authentication_service_db;Port=3305;Database=authenticationdb;Uid=root;Pwd=secret;"
 }
}

所以我不知道如何调试或下一步该怎么做。使用docker compose时没有连接。

Answer 1

您将端口3306映射到3305到开发应用程序的主机。因此，您可以在端口3305上连接到db。但是，您仍在使用容器内部的端口3305。由于您的服务（authentication_service_db）正在监听端口3306，而不是3305，因此您的应用程序无法连接数据库。

您必须更改连接字符串以使用端口3306，而不是3305。

码头工人组成后无法连接到mysql数据库

1 个答案: