在 Docker Compose 中获取"MongooseServerSelectionError: connect ECONNREFUSED 127.0.0.1:27017"

我正在用Express和MongoDB做一个REST API。在当地一切都很顺利。我想使用Docker Compose对数据库和后端进行dockerize。

Mongo Docker运行得很好，但后端无法连接到它。它不断向我抛出这个错误：

/backend/node_modules/mongoose/lib/connection.js:797
const serverSelectionError = new ServerSelectionError();
^

MongooseServerSelectionError: connect ECONNREFUSED 127.0.0.1:27017
at NativeConnection.Connection.openUri (/backend/node_modules/mongoose/lib/connection.js:797:32)
at /backend/node_modules/mongoose/lib/index.js:341:10
at /backend/node_modules/mongoose/lib/helpers/promiseOrCallback.js:32:5
at new Promise (<anonymous>)
at promiseOrCallback (/backend/node_modules/mongoose/lib/helpers/promiseOrCallback.js:31:10)
at Mongoose._promiseOrCallback (/backend/node_modules/mongoose/lib/index.js:1167:10)
at Mongoose.connect (/backend/node_modules/mongoose/lib/index.js:340:20)
at Object.<anonymous> (/backend/index.js:11:3)
at Module._compile (node:internal/modules/cjs/loader:1097:14)
at Object.Module._extensions..js (node:internal/modules/cjs/loader:1149:10) {
reason: TopologyDescription {
type: 'Unknown',
servers: Map(1) {
'localhost:27017' => ServerDescription {
_hostAddress: HostAddress { isIPv6: false, host: 'localhost', port: 27017 },
address: 'localhost:27017',
type: 'Unknown',
hosts: [],
passives: [],
arbiters: [],
tags: {},
minWireVersion: 0,
maxWireVersion: 0,
roundTripTime: -1,
lastUpdateTime: 14312460,
lastWriteDate: 0,
error: MongoNetworkError: connect ECONNREFUSED 127.0.0.1:27017
at connectionFailureError (/backend/node_modules/mongodb/lib/cmap/connect.js:293:20)
at Socket.<anonymous> (/backend/node_modules/mongodb/lib/cmap/connect.js:267:22)
at Object.onceWrapper (node:events:510:26)
at Socket.emit (node:events:390:28)
at emitErrorNT (node:internal/streams/destroy:164:8)
at emitErrorCloseNT (node:internal/streams/destroy:129:3)
at processTicksAndRejections (node:internal/process/task_queues:83:21)
}
},
stale: false,
compatible: true,
heartbeatFrequencyMS: 10000,
localThresholdMS: 15,
logicalSessionTimeoutMinutes: undefined
}
}

我在网上读到，问题可能是我不应该连接到localhost，而是连接到MongoDB容器。

我附上文件：

docker-compose.yml

version: '3.8'
services:
data:
container_name: data
image: mongo
ports:
- 27017:27017
volumes:
- ./data/db:/data/db

backend:
container_name: backend
depends_on:
- data
build: ./backend
ports:
- 5000:5000
environment:
- DB_HOST=data
- DB_NAME=${DB_NAME?:}
- DB_PORT=${DB_PORT?:}

/后端/Dockerfile

# pull official base image
FROM node:latest
# set working directory
WORKDIR /backend
EXPOSE 5000
ENV PORT=5000
ENV HOST=0.0.0.0
# install backend dependencies
COPY package*.json ./
RUN npm ci --only-production
# add backend
COPY . .
# start backend
CMD npm start

/backend/index.js

const express = require("express")
const mongoose = require("mongoose")
const property = require("./routes/property-router")
const properties = require("./routes/properties-router")
const statistics = require("./routes/statistics-router")
const bodyParser = require("body-parser")
const dbConfig = require("./config/db.config")
require("dotenv").config();
var cors = require("cors")

// Connect to MongoDB database
mongoose
.connect(dbConfig.url, { useNewUrlParser: true })
.then(() => {
const app = express()
app.use(cors())
app.use(bodyParser.text({ type: '*/*'}))
app.use("/api", statistics)
app.use("/api", properties)
app.use("/api", property)
const PORT = dbConfig.port || 5000;
app.listen(PORT, () => {
console.log(`Server is running on port ${PORT}.`);
});
})

/backend/config/db.config.js

require('dotenv').config();
const {
DB_HOST,
DB_PORT,
DB_NAME,
PORT,
} = process.env;

module.exports = {
url: `mongodb://${DB_HOST}:${DB_PORT}/${DB_NAME}`,
port: PORT
};

/后端/.env

PORT=5000
HOST=localhost
DB_HOST=localhost
DB_NAME=propertyDB
DB_PORT=27017

在本地运行后端，我可以毫无问题地连接到MongoDB Docker。通过只在Docker Compose文件中保留数据并运行node index.js.

我做错了什么？

编辑

我甚至将URL从index.js更改为随机URL，但仍然保持相同的错误，并尝试连接到127.0.0.1:27017。

.connect("randomurl.com", { useNewUrlParser: true })