how to subtract two time from each other in nodejs, mongodb

Question

I have two time data here. one is from mongodb database which i finded by objectId. other one is currenttime. i put both in variables.. now i want to subtract the time value of database from current time.. here is some code which i tried.

var mongo = require('mongodb');
var ObjectId = require('mongodb').ObjectID;
var lastUpdate = new Date();
var id = ObjectId("5a5ee7588a6a102398be8ada");
var MongoClient = require('mongodb').MongoClient;
var url = "mongodb://localhost:27017/blue";

MongoClient.connect(url, function (err, db) {
    if (err) 
        throw err;
    var dbase = db.db("blue");
    dbase.collection("screams").findOne({ email: "Adnan@gmail.com", _id: id }, 
     function (err, searchtype) {
        if (err) 
          throw err;
        var resdate = searchtype.createdAt;
        console.log(resdate);
        dbase.collection("screams").find(function () {
            return (this.lastUpdate.valueOf() - this.resdate.valueOf())
                > (1000 * 60 * 60 * 24);
        })
        db.close();
    });
});

Answer 1

MongoDb has $subtract operator in its aggregation framework can help you to achieve this purpose I think.

Try

dbase.collection('screams').aggregate([
    {$match:{email:"Adnan@gmail.com", _id: id }},
    {$project:{_id:1, email:1, createdAt:1, 
         datediff:{$subtract:[new Date(), '$createdAt']}}
    }
], function(err, result) {
    //Do what you need to do here.
})

The datediff is in unit of milliseconds, you might need to do some conversion there to meet your need.

Answer 2

luckily I found a simple solution. use it if any body confronted with same problem

var d1 = new Date(); , // put ur any date value in the given variable
        d2 = new Date();

        var diff = Math.abs(d2 - d1);
        console.log(diff);