unable to use $match operator for mongodb/mongoose aggregation with ObjectId

Question

Relatively Simple Scenario:

I have this Voucher object which has a user property (of type ObjectId). I want to get the sum of

Answer 1

When using the find method or findById the query can be only:

var query = {
    $or: [
        {'_sender':req.body._id},
        {'_recipient':req.body._id}
    ]
};

When using aggregate the query need a cast

var mongoose = require('mongoose');
var query = {
    $or: [
        {'_sender':new mongoose.Types.ObjectId(decoded._id)},
        {'_recipient':new mongoose.Types.ObjectId(decoded._id)}
    ]
};