如何从我的 get 请求中从 MongoDB 文档中提取正文？

Question

I am trying to access the Question field in the body of a JSON document inside a MongoDB. When I run the GET request I get something that looks like this:

{
"_readableState": {
    "objectMode": true,
    "highWaterMark": 0,
    "buffer": {
        "head": null,
        "tail": null,
        "length": 0
    },
    "length": 0,
    "pipes": null,
    "pipesCount": 0,
    "flowing": null,
    "ended": false,
    "endEmitted": false,
    "reading": false,
    "sync": true,
    "needReadable": false,
    "emittedReadable": false,
    "readableListening": false,
    "resumeScheduled": false,
    "destroyed": false,
    "defaultEncoding": "utf8",
    "awaitDrain": 0,
    "readingMore": false,
    "decoder": null,
    "encoding": null
},
"readable": true,
"domain": null,
"_events": {},
"_eventsCount": 0,
"_opts": {},
"_destroyed": false
}

I was reading about JSON body parsers but adding that does not seem to be working. Here is my index.js :

 var express = require('express')
 var mongojs = require('mongojs')
 var bodyParser = require("body-parser");
 var app = express()
 var db = require('./myDB.js')

 app.use(bodyParser.urlencoded({ extended: false }));
 app.use(bodyParser.json());

 app.use(express.json())
 app.listen(4000, () => console.log('Hello'))

 app.get('/getFlashCard', (req, res) => {
 let flashID = req.body._id;
 db.getFlashCard("Interview Questions", flashID, function(docs) {
    console.log("Flashcard retrieved: ", docs);
        res.send(docs);
    });
 });

Here is my myDB.js :

getFlashCard : function(colName, flashID, callback) {
    let data = mongodb.collection("Interview Questions").find({
        "_id" : flashID
    });
    callback(data);
}

Answer 1

here you are returning the promise model instead of the actual resolved data.

getFlashCard : async function(colName, flashID, callback) {
 const data = await mongodb.collection("Interview Questions").find({_id : flashID });

   callback(data);
}

Answer 2

Notice that you are not waiting for the find to finish, instead you are assigning data to mongodb.collection("").find

You need to wait for find to finish by either using a callback (check out https://mongodb.github.io/node-mongodb-native/api-generated/collection.html#find ) or by using async/await.