使用docker-compose部署后端与Mongo容器时遇ECONNREFUSED错误

执行docker-compose up后，Node应用容器启动约20秒后抛出连接拒绝错误，核心错误信息如下：

MongooseServerSelectionError: connect ECONNREFUSED 127.0.0.1:27017

完整错误日志：

(node:33) [MONGOOSE] DeprecationWarning: Mongoose: the `strictQuery` option will be switched back to `false` by default in Mongoose 7. Use `mongoose.set('strictQuery', false);` if you want to prepare for this change. Or use `mongoose.set('strictQuery', true);` to suppress this warning.
(Use `node --trace-deprecation ...` to show where the warning was created)
Server listening on port 3000
/cloudband/node_modules/mongoose/lib/connection.js:825
  const serverSelectionError = new ServerSelectionError();
                               ^

MongooseServerSelectionError: connect ECONNREFUSED 127.0.0.1:27017
    at Connection.openUri (/cloudband/node_modules/mongoose/lib/connection.js:825:32)
    at /cloudband/node_modules/mongoose/lib/index.js:409:10
    at /cloudband/node_modules/mongoose/lib/helpers/promiseOrCallback.js:41:5
    at new Promise (<anonymous>)
    at promiseOrCallback (/cloudband/node_modules/mongoose/lib/helpers/promiseOrCallback.js:40:10)
    at Mongoose._promiseOrCallback (/cloudband/node_modules/mongoose/lib/index.js:1262:10)
    at Mongoose.connect (/cloudband/node_modules/mongoose/lib/index.js:408:20)
    at Object.<anonymous> (/cloudband/server/server.js:15:4)
    at Module._compile (node:internal/modules/cjs/loader:1239:14)
    at Module._extensions..js (node:internal/modules/cjs/loader:1293:10) {
  reason: TopologyDescription {
    type: 'Unknown',
    servers: Map(1) {
      'localhost:27017' => ServerDescription {
        address: 'localhost:27017',
        type: 'Unknown',
        hosts: [],
        passives: [],
        arbiters: [],
        tags: {},
        minWireVersion: 0,
        maxWireVersion: 0,
        roundTripTime: -1,
        lastUpdateTime: 28094812,
        lastWriteDate: 0,
        error: MongoNetworkError: connect ECONNREFUSED 127.0.0.1:27017
            at connectionFailureError (/cloudband/node_modules/mongodb/lib/cmap/connect.js:387:20)
            at Socket.<anonymous> (/cloudband/node_modules/mongodb/lib/cmap/connect.js:310:22)
            at Object.onceWrapper (node:events:628:26)
            at Socket.emit (node:events:513:28)
            at emitErrorNT (node:internal/streams/destroy:151:8)
            at emitErrorCloseNT (node:internal/streams/destroy:116:3)
            at process.processTicksAndRejections (node:internal/process/task_queues:82:21) {
          cause: Error: connect ECONNREFUSED 127.0.0.1:27017
              at TCPConnectWrap.afterConnect [as oncomplete] (node:net:1495:16) {
            errno: -111,
            code: 'ECONNREFUSED',
            syscall: 'connect',
            address: '127.0.0.1',
            port: 27017
          },
          [Symbol(errorLabels)]: Set(1) { 'ResetPool' }
        },
        topologyVersion: null,
        setName: null,
        setVersion: null,
        electionId: null,
        logicalSessionTimeoutMinutes: null,
        primary: null,
        me: null,
        '$clusterTime': null
      }
    },
    stale: false,
    compatible: true,
    heartbeatFrequencyMS: 10000,
    localThresholdMS: 15,
    setName: null,
    maxElectionId: null,
    maxSetVersion: null,
    commonWireVersion: 0,
    logicalSessionTimeoutMinutes: null
  },
  code: undefined
}

当前配置文件 #

Dockerfile #

FROM node:19.4.0

WORKDIR /cloudband

COPY package.json /cloudband/
COPY package-lock.json /cloudband/

RUN npm ci 

COPY .env /cloudband/
COPY server /cloudband/server/

EXPOSE 3000 

CMD ["npm", "run", "dev:server"]

docker-compose.yml #

version: '3'
services:
  mongo:
    image: mongo
    container_name: mongo
    ports:
      - 27017:27017
    environment:
      - MONGO_INITDB_ROOT_USERNAME=admin
      - MONGO_INITDB_ROOT_PASSWORD=password
  cloudband:
    image: cloudband
    container_name: cloudband
    ports:
      - 3000:3000
    command: npm run dev:server
networks:
  app:

已尝试的排查操作 #

• 确认容器处于同一网络且可互相ping通
• 在docker-compose中添加links配置
• 检查端口、主机、IP配置
• 切换多种MONGO_URI格式：

  # MONGO_URI_=mongodb://admin:password@localhost:27017/dbname
  MONGO_URI_=mongodb://localhost:27017/dbname
  # MONGO_URI_=mongodb://127.0.0.1:27017/dbname
  

解决方案 #

1. 修正MongoDB连接字符串 #

在Docker Compose的默认网络中，容器只能通过服务名互相访问，localhost或127.0.0.1指向容器自身，而非Mongo容器。同时因为你给Mongo配置了root用户名和密码，连接字符串必须包含认证信息，且指定认证源为admin数据库：

修改.env中的连接字符串：

MONGO_URI=mongodb://admin:password@mongo:27017/dbname?authSource=admin

2. 添加容器启动依赖 #

在docker-compose.yml的cloudband服务中添加depends_on，确保Mongo容器先于应用容器启动（注意：这仅保证启动顺序，不保证Mongo完全就绪）：

cloudband:
  image: cloudband
  container_name: cloudband
  ports:
    - 3000:3000
  command: npm run dev:server
  depends_on:
    - mongo

3. 处理MongoDB连接就绪等待 #

Mongo容器启动后需要几秒时间初始化，应用直接连接可能失败，可通过两种方式解决：

• 代码层面添加重试逻辑：在Mongoose连接配置中添加重试参数：

  const mongoose = require('mongoose');
  mongoose.connect(process.env.MONGO_URI, {
    retryWrites: true,
    w: 'majority',
    connectTimeoutMS: 10000,
    socketTimeoutMS: 45000,
    autoReconnect: true,
    maxPoolSize: 10
  });
  

• 使用等待脚本：在应用启动命令前加入等待逻辑，确保Mongo端口就绪后再启动应用。修改docker-compose.yml的command：

  command: >
    sh -c "until nc -z mongo 27017; do echo waiting for mongo; sleep 2; done; npm run dev:server"
  

  （若容器内无netcat工具，需在Dockerfile中添加RUN apt-get update && apt-get install -y netcat）

4. 修复strictQuery警告（可选） #

为消除Mongoose的deprecation警告，在应用启动代码（如server.js）中添加：

const mongoose = require('mongoose');
mongoose.set('strictQuery', false); // 或true，根据需求选择

内容的提问来源于stack exchange，提问作者John Donovan