Question

嘿，所以我有一个学校作业，要求我用mongoose和koa连接到mongodb数据库。我在Docker上建立了数据库，我可以通过mongodb Compass访问它，所以应该可以。但是当我尝试使用猫鼬时，我在docker显示器上收到一条错误消息。

我的代码：

server.js

const Koa = require('koa');
const mongoose = require('mongoose');

const router = require('./routes');


const app = new Koa();
app.use(require('koa-body')());
app.use(router.routes());

mongoose.connect(process.env.MONGODB_URI, { useNewUrlParser: true, useUnifiedTopology: true })
    .then(() => {
        const listener = app.listen(process.env.APP_PORT || 3000, () =>
            console.log('App started on port ' + listener.address().port)
        )
    })
    .catch((error) => {
        console.log(error)
        process.exit(1)
    })

//    app.proxy = true;
module.exports = app;

docker-compose.yml

mongodb:
    image: 'mongo:4.4.0'
    command: '--auth'
    container_name: mongodb_container
    volumes:
      - './data/mongo:/data/db:delegated'
    ports:
      - '27017:27017'
    environment: 
      MONGO_INITDB_ROOT_USERNAME: root
      MONGO_INITDB_ROOT_PASSWORD: example
      MONGO_INITDB_DATABASE: database1

  node-service-two:
    depends_on:
      - mongodb
    build:
      context: '../Test-II-node'
    ports:
      - '3000:3000'
    volumes:
      - '../Test-I-node:/home/node/app:delegated'
    environment:
      MONGODB_URI: mongodb://root:example@localhost:27017/two?authSource=admin
    command: 'run dev'

package.json中的脚本


  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "start": "node src/server.js",
    "dev": "nodemon src/server.js"
  }

错误消息

[nodemon] starting `node src/server.js`

MongooseServerSelectionError: connect ECONNREFUSED 127.0.0.1:27017

at NativeConnection.Connection.openUri (/home/node/app/node_modules/mongoose/lib/connection.js:800:32)

at /home/node/app/node_modules/mongoose/lib/index.js:341:10

at /home/node/app/node_modules/mongoose/lib/helpers/promiseOrCallback.js:31:5

at new Promise (<anonymous>)

at promiseOrCallback (/home/node/app/node_modules/mongoose/lib/helpers/promiseOrCallback.js:30:10)

at Mongoose.connect (/home/node/app/node_modules/mongoose/lib/index.js:340:10)

at Object.<anonymous> (/home/node/app/src/server.js:11:10)

at Module._compile (internal/modules/cjs/loader.js:1075:30)

at Object.Module._extensions..js (internal/modules/cjs/loader.js:1096:10)

at Module.load (internal/modules/cjs/loader.js:940:32)

at Function.Module._load (internal/modules/cjs/loader.js:781:14)

at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:72:12)

at internal/main/run_main_module.js:17:47 {

reason: TopologyDescription {

type: 'Single',

setName: null,

maxSetVersion: null,

maxElectionId: null,

servers: Map(1) { 'localhost:27017' => [ServerDescription] },

stale: false,

compatible: true,

compatibilityError: null,

logicalSessionTimeoutMinutes: null,

heartbeatFrequencyMS: 10000,

localThresholdMS: 15,

commonWireVersion: null

}
}

[nodemon] app crashed - waiting for file changes before starting...

我很确定它与javascript Promise有关，或者它找不到mongodb url，但我无法查明问题。我还安装了所有必需的软件包。这是我第一次使用node，所以任何帮助都会很棒。

Answer 1

使用docker-compose时，您必须记住每个服务都是其自己的容器。当您的Node.js服务正在寻找 localhost 时，它正在寻找自身。

要使用在docker-compose中指定的服务名称，在MongoDB容器上固定此点猫鼬：MONGODB_URI: mongodb://root:example@mongodb:27017/two?authSource=admin

无法使用猫鼬连接到mongodb数据库

1 个答案: