数据未使用Mongoose保存在MongoDB中

Question

I am newbie in Nodejs world. I am trying to insert data in MongoDB using Mongoose. The idea is
- I will have a server running on node - any incoming POST data will be saved in Mongo.

The problem when the below code is run no data gets saved in MongoDB and also no error is shown. Am i missing something here. Any help will be really appreciated.

I have the below code that writes data in mongoDB for an incoming http request.

var http = require('http') // http module
, fs = require('fs')  // file system module
, qs = require('querystring') // querystring parser
, mongoose = require('mongoose'); 

mongoose.connect("mongodb://localhost/app_data_db");
var db = mongoose.connection;
var appDataSchema = new mongoose.Schema({

    record_id:      Number,
    app_version:    Number,
    imei:           String,
    created_time:   Date,
    device_uid:     String,
    model:          String
});

var appDataModel = mongoose.model("app_data_collection",appDataSchema);

var PORT=8080;

http.createServer(function(req,res){

if(req.method == "POST") {
    var POST = {};
    //parse query string
    req.on('data', function(data) {
        data = data.toString();
        data = data.split('&');
        for (var i = 0; i < data.length; i++) {
           var _data = data[i].split("=");
           POST[_data[0]] = _data[1];
        }

        db.once('open', function (callback) {
            appDataModel.create({
                  record_id:      POST["id"],
                  app_version:    POST["app_version"],
                  imei:           POST["imei"],
                  created_time:   new Date((parseInt(POST["created_time"]) + 19800) *1000), // to set correct time zone IST
                  device_uid:     POST["device_uid"],
                  model:          POST["model"]

                });
        });
        res.writeHead(200, {'Content-Type': 'text/plain'});
        res.end('saved to DB:'+POST["id"]+'\n');
        console.log('saved to DB:'+POST["id"]+'\n');
    });
    mongoose.disconnect();
}


}).listen(PORT);

To test this I am manually firing this curl call:

curl -X POST --data "id=58648148&app_version=4.8&imei=355886053224492&created_time=1417372202&device_uid=e385c8a5a4c01304&model=GT-I9082" http://localhost:8080

Answer 1

There are couple problems with your code:

1) you call mongoose.disconnect outside of the callback, which means that it's called before the callback is executed

2) you're creating the model inside the callback, but sending the response outside of it, so the response is sent before the model is created

3) and finally create method provides a callback when the entity is saved to the db, which you don't use it all

Here's the modified code:

mongoose.connect("mongodb://localhost/app_data_db");
db.on('open', function() {
    http.createServer(function(req, res) {

        if(req.method == "POST") {
            var POST = {};
            //parse query string
            req.on('data', function(data) {
                data = data.toString();
                data = data.split('&');
                for (var i = 0; i < data.length; i++) {
                    var _data = data[i].split("=");
                    POST[_data[0]] = _data[1];
                }    

                appDataModel.create({
                  record_id:      POST["id"],
                  app_version:    POST["app_version"],
                  imei:           POST["imei"],
                  created_time:   new Date((parseInt(POST["created_time"]) + 19800) *1000), // to set correct time zone IST
                  device_uid:     POST["device_uid"],
                  model:          POST["model"]        
                }, 
                function(err){
                    res.writeHead(200, {'Content-Type': 'text/plain'});
                    res.end('saved to DB:'+POST["id"]+'\n');
                    console.log('saved to DB:'+POST["id"]+'\n');
                    mongoose.disconnect();
               });                    
           });    
        }        
    }).listen(PORT);
});

Answer 2

I think I got this working. I have moved the mongoose connection inside. Rest all is same. Since I wanted to post the code hence answering instead of commenting. This may help others. Here is the complete code

var http = require('http') // http module
    , fs = require('fs')  // file system module
    , qs = require('querystring') // querystring parser
    , mongoose = require('mongoose');

var appDataSchema = new mongoose.Schema({
         record_id: Number,
         app_version: Number,
         imei: String,
         created_time: Date,
         device_uid: String,
         model: String
    });

var appDataModel = mongoose.model("app_data_collection", appDataSchema);

var PORT = 8080;

http.createServer(function(req, res) {

    if (req.method == "POST") {

        var POST = {};
        //parse query string
        req.on('data', function(data) {
            data = data.toString();
            data = data.split('&');
            for (var i = 0; i < data.length; i++) {
                var _data = data[i].split("=");
                POST[_data[0]] = _data[1];
            }

            mongoose.connect("mongodb://localhost/app_data_db");
            var db = mongoose.connection;

            db.on('error', console.error.bind(console, 'connection error:'));

            db.once('open', function() {
                appDataModel.create({
                record_id: POST["id"],
                app_version: POST["app_version"],
                imei: POST["imei"],
                created_time: new Date((parseInt(POST["created_time"]) + 19800) * 1000), // to set correct time zone IST
                device_uid: POST["device_uid"],
                model: POST["model"]

            }, function(err) {
                res.writeHead(200, {'Content-Type': 'text/plain'});
                res.end('saved to DB:' + POST["id"] + '\n');
                console.log('saved to DB:' + POST["id"] + '\n');
                mongoose.disconnect();
            });
        });
    });
  }

}).listen(PORT);