Using Sequences With Mongoose (MongoDB)

A good reference of creating sequence and using it can be found at
https://docs.mongodb.org/manual/tutorial/create-an-auto-incrementing-field/

This can be achieved in Mongoose,

1) Step 1
From mongo shell  create the counter collection as below
db.counters.insert({_id: "userid",seq: 0})


2)
create a counter schema as below (counter.js )


var mongoose = require('mongoose');

var counterSchema = {
    _id: {type: String, required: true},
    seq: { type: Number, default: 0 }
};


module.exports = mongoose.model('Counter', counterSchema);

3) Use it (for example -- UserHandler.js)

var mongoose = require('mongoose');
mongoose.connect('mongodb://localhost:27017/cchPerfApp');

var User = require('../model/user');
var counter = require('../model/counter');

var saveRequest = function() {
    counter.findByIdAndUpdate({_id: 'userid'}, {$inc: { seq: 1} }, function(error, counter)   {
        if(error) {
            console.log(error)
        }else {
            var user = new User();
            user._id = counter.seq;
            user.name = "xyz"
user.save(function(err){
}
        }  
}
}