无法连接到 MongoDB，错误消息

Question

我正在尝试连接到 Mongo Db 我的代码如下；

import express from "express";
import dotenv from "dotenv";
import mongoose from "mongoose";
import cors from "cors";
import cookieParser from "cookie-parser";

dotenv.config();
const app = express();
const port = process.env.PORT || 8000;

// //for testing
// app.get("/", (req, res) => {
//   res.send("api is working");
// });

//database connect
// tourbooking tour1992

mongoose.set("strictQuery", false);
const connect = async () => {
  try {
    await mongoose.connect(process.env.MONGO_URI, {
      useNewUrlParser: true,
      useUnifiedTopology: true,
    });

    console.log("MongoDB database connected");
  } catch (err) {
    console.log("MongoDB database connection failed");
  }
};

// middleware
app.use(express.json());
app.use(cors());
app.use(cookieParser());

app.listen(port, () => {
  console.log("server listening on port", port);
});

输出如下；

[nodemon] restarting due to changes...
[nodemon] starting `node index.js`
server listening on port 4000

但未连接到服务器消息未显示，并且控制台有以下错误：

请帮忙解决上述代码问题？再说一遍，我在编码方面还是个小孩，非常感谢您提前提供的帮助

Answer 1

您应该调用

connect

方法并声明路线：

// //for testing
app.get("/", (req, res) => {
   res.send("api is working");
});

// middleware
app.use(express.json());
app.use(cors());
app.use(cookieParser());

mongoose.set("strictQuery", false);
mongoose.connect(process.env.MONGO_URI, {
  useNewUrlParser: true,
  useUnifiedTopology: true,
}).then(() => {
  console.log("MongoDB database connected");

  app.listen(port, () => {
    console.log("server listening on port", port);
  });
}).catch(err => {
  console.log("MongoDB database connection failed");
});