Docker Compose 使用 MySQL 和 NodeJS 时出现错误 ECONNREFUSED 127.0.0.1:3306

Question

我尝试在 Windows 10 主机中使用 Docker Compose 为我的 NestJS + TypeORM + MySQL 环境设置一些容器，但收到 ECONNREFUSED 错误：

connect ECONNREFUSED 127.0.0.1:3306 +2ms
backend_1  | Error: connect ECONNREFUSED 127.0.0.1:3306
backend_1  |     at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1145:16)
backend_1  |     --------------------
backend_1  |     at Protocol._enqueue (/usr/src/app/node_modules/mysql/lib/protocol/Protocol.js:144:48)
backend_1  |     at Protocol.handshake (/usr/src/app/node_modules/mysql/lib/protocol/Protocol.js:51:23)        
backend_1  |     at PoolConnection.connect (/usr/src/app/node_modules/mysql/lib/Connection.js:116:18)
backend_1  |     at Pool.getConnection (/usr/src/app/node_modules/mysql/lib/Pool.js:48:16)
backend_1  |     at /usr/src/app/node_modules/typeorm/driver/mysql/MysqlDriver.js:793:18
backend_1  |     at new Promise (<anonymous>)
backend_1  |     at MysqlDriver.createPool (/usr/src/app/node_modules/typeorm/driver/mysql/MysqlDriver.js:790:16)
backend_1  |     at MysqlDriver.<anonymous> (/usr/src/app/node_modules/typeorm/driver/mysql/MysqlDriver.js:278:51)
backend_1  |     at step (/usr/src/app/node_modules/typeorm/node_modules/tslib/tslib.js:141:27)
backend_1  |     at Object.next (/usr/src/app/node_modules/typeorm/node_modules/tslib/tslib.js:122:57)

我创建了以下内容Dockerfile来配置 NestJS API 容器：

FROM node:12-alpine
WORKDIR /usr/src/app

COPY package.json .
RUN npm install

EXPOSE 3000

#CMD ["npm", "start"]

CMD /wait-for-it.sh db:3306 -- npm start

COPY . .

然后我从 Docker Compose 中引用了以下内容docker-compose.yml：

version: "3.8"

networks:
  app-tier:
    driver: bridge

services:
  db:
    image: mysql
    command: --default-authentication-plugin=mysql_native_password
    restart: always
    expose:
      - "3306"
    ports:
      - "3306:3306"    
    networks:
      - app-tier      
    environment:
      MYSQL_DATABASE: school
      MYSQL_ALLOW_EMPTY_PASSWORD: ok
      MYSQL_ROOT_PASSWORD: root
      MYSQL_USER: dbuser
      MYSQL_PASSWORD: dbuser
      MYSQL_ROOT_HOST: '%'
  backend:
    depends_on:
      - db
    build: .
    ports:
      - "3000:3000"
    networks:
      - app-tier      

最后，我设置 TypeORM 配置以与 Docker Compose 文件匹配：

export const DB_CONFIG: TypeOrmModuleOptions = {
    type: 'mysql',
    host: 'db',
    port: 3306,
    username: 'dbuser',
    password: 'dbuser',
    database: 'school',
    entities: [], // We specify the entities in the App Module.
    synchronize: true,
};

我对 Docker Compose 有点陌生，但我尝试了很多事情，例如将输出端口更改为 3307、设置显式网络...并且当我运行它时，端口 3306 在我的主机操作系统中是空闲的。有什么帮助吗？

编辑1

我已包含MYSQL_ROOT_HOST并wait-for-it.sh按照建议进行操作，但仍然没有结果。

Answer 1

我认为您的数据库需要更多时间来启动，并且您的应用程序在数据库之前启动，请为您的 docker-compose.yml 文件尝试类似的操作：

version: "3.8"

networks:
  app-tier:
    driver: bridge

services:
  db:
    image: mysql
    command: --default-authentication-plugin=mysql_native_password
    restart: always
    expose:
      - "3306"
    ports:
      - "3306:3306"    
    networks:
      - app-tier      
    environment:
      MYSQL_DATABASE: school
      MYSQL_ALLOW_EMPTY_PASSWORD: ok
      MYSQL_ROOT_PASSWORD: root
      MYSQL_USER: dbuser
      MYSQL_PASSWORD: dbuser
      MYSQL_ROOT_HOST: '%'
  backend:
    depends_on:
      - db
    build: .
    command: bash -c 'while !</dev/tcp/db/3306; do sleep 1; done; npm start'
    ports:
      - "3000:3000"
    networks:
      - app-tier