我正在使用express和mongodb在服务器上创建应用程序。我以前在开发此应用程序方面做得很好，直到做了一个小的更改，我的所有查询都无法在mongodb上工作。我对连接字符串进行了三重检查，邮递员的输出已到达该函数，但从未触发mongodb查询回调。

这是我的server.js

require("dotenv").config();
const express = require("express");
const bodyParser = require("body-parser");
const cors = require("cors");
const authenticationController = require("./controllers/authenticationController");
const mainactionsController = require("./controllers/mainactionsController");

const app = express();
app.use(bodyParser.urlencoded({ extended: false }));
app.use(bodyParser.json());
app.use(cors());

// all user actions
app.use("/auth",authenticationController);

app.use("/memoryleak",mainactionsController);

// Fail safe. Here's our classic 404 error :P
app.all("*",(req,res) => {
  res
    .status(404)
    .send(
      "Sorry,the content you were looking for was not found. The classic 404 "
    );
});

const port = process.env.PORT || 3001;
app.listen(port,function() {
  console.log("Express server listening on port " + port);
});

module.exports = { app };

这是我的mainactionsController的一个片段，该片段在上方触发并使用了路由器...

const router = express.Router();
const mongoose = require("mongoose");
const { Questions,Replies,Users } = require("../dbschema");
const repliesController = require("./repliesController");
const questionController = require("./questionController");
const notificationController = require("./notificationsController");

router.get("/getQuestionById/:id",res) => {
  questionController.getQuestionById(req,res,Questions,mongoose);
});
router.get("/questions",res) => {
  questionController.getallQuestions(req,Questions);
});

module.exports = router;

这是我的getallQuestions函数：

const getallQuestions = (req,Questions) => {
  console.log("got to the correct function");
  Questions.find({},(err,docs) => {
    console.log("hello? CAN YOU HEAR ME");
    console.log(err,docs);
    if (err) {
      console.log(err);
      return res.status(400).send(err);
    }
    console.log(docs);
    return res.status(200).send(docs);
  });
};

当邮递员打到路由时，将到达所有这些控制台日志，但是回调函数内部没有任何记录，并且连接只是挂起。

最后，这是我的数据库架构

const mongoose = require("mongoose");
const UserSchema = new mongoose.Schema({
  username: { type: String,unique: true,required: true },passWord: { type: String,questionsAsked: { type: Array,repliesGiven: { type: Array,itemsLiked: { type: Array,notifications: { type: Array,required: true }
});
const QuestionSchema = new mongoose.Schema({
  title: { type: String,questionBody: { type: String,numReplies: { type: Number,numLikes: { type: Number,numVotes: { type: Number,tags: { type: Array,contributor: { type: String,required: true }
});
const ObjectId = mongoose.Schema.Types.ObjectId;
const ReplySchema = new mongoose.Schema({
  questionID: ObjectId,title: String,questionBody: String,numLikes: Number,numVotes: Number,contributor: String
});

mongoose.model("Reply",ReplySchema);
mongoose.model("Question",QuestionSchema);
mongoose.model("User",UserSchema);

module.exports = {
  Questions: mongoose.model("Question"),Replies: mongoose.model("Reply"),Users: mongoose.model("User")
};[1]

任何反馈将不胜感激。