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I am trying to use Mongoose/ MongoDb's aggregate function to match documents based on the date. While my aggregate function matches documents by other filters, It is simply not working based on date. I am sharing my code below.

"$match": 
 "createdAt": "$lt": new Date()

I was trying a variety of different dates, Starting with the ISO date stored in my mongoDb database, But none of them seem to work. I have no idea what is the reason for this issue. While I had searched online extensively, I did not find anything conclusive. The same query executed over the mongoDb shell works fine, Leading me to believe that this may be an issue with Mongoose and the way it casts the Date.

This is the data I was testing with

 "_id" : ObjectId("5be7fc909625592852d422b4"),
 "time" : ISODate("2018-11-11T09:55:28.704Z"),
 "receiver" : ObjectId("5be5d727d3f24e06b144e229"),
 "createdAt" : ISODate("2018-11-11T09:55:28.718Z"),
 "updatedAt" : ISODate("2018-11-11T09:55:28.718Z"),


 "_id" : ObjectId("5be807902b789e5c3c05dc5e"),
 "time" : ISODate("2018-11-11T10:42:24.410Z"),
 "receiver" : ObjectId("5be5d727d3f24e06b144e229"),
 "createdAt" : ISODate("2018-10-09T18:30:00Z"),
 "updatedAt" : ISODate("2018-10-09T18:30:00Z"),

I am stuck, With no idea how to proceed ahead. I have tried everything from my understanding but nothing seems to work. I hope I can get some help on this issue.

Much appreciated, Thanks.

You are possibly facing a timezone problem. I just tried the call of new Date().getTimezoneOffset() inside node and inside mongo. Both return different results (node returns -60, mongo shell returns 0 on my machine).

You can remove the timezone offset with the following code:

let d = new Date()
var offset = d.getTimezoneOffset() * 60000 // This converts the given minutes to milliseconds.
var utc = d.getTime() + offset
var nd = new Date(utc)

"$match": 
 "createdAt": "$lt": nd 

When you convert the time you should now get the expected results.

This is sensible as MongoDB uses UTC as time format. The conversion might seem a bit cumbersome in vanilla JavaScript. You could alternatively use a library like moment.js.