mongo module export issue with cross referencing files in node js

Question

I have 2 files Stats.js and Stock.js. Both files need access to other file , so I have to add require(Stock) in Stats and vice versa. But while executing createstats() in Stats.js , it gives aggregate is not a function in Stock. Issue is not there when I comment

** var Stats = require('../Stats'); line in Stock.js. **

How to overcome this issue. pl help. Thanks

File1: Stats.js

var mongoose     = require('mongoose');
var Stock    = require('../Stock');
var logger   = require('../../util/log');
var Schema  = mongoose.Schema;
var StatsSchema   = new Schema({
    item:String,
    pqty:Number,
    sqty:Number,
    date:Date,
});


function createstats () {

    Stock.aggregate([

    .....
    .....
    ])
}
module.exports = mongoose.model('Stats', StatsSchema);

---

FIle2: Stock.js

    var mongoose     = require('mongoose');    
    var Stats    = require('../Stats');
    var logger   = require('../../util/log');
    var Schema       = mongoose.Schema;    

    var StockSchema   = new Schema({
     supplier:String,
     name:Number,
     rate:Number,
     date:Date,   
    });

    function updateqty () {
        Stats.update(

        .....
        .....
        )
    }
    module.exports = mongoose.model('Stock', StockSchema);

Answer 1

This is the I have solved the problem. I have added one more file called Schemas.js as below

Schemas.js

 var mongoose     = require('mongoose');    
    var Stats    = require('../Stats');
    var logger   = require('../../util/log');
    var Schema       = mongoose.Schema;    

    var StockSchema   = new Schema({
     supplier:String,
     name:Number,
     rate:Number,
     date:Date,   
    });

var StatsSchema   = new Schema({
    item:String,
    pqty:Number,
    sqty:Number,
    date:Date,
});



module.exports = {
    StatsSchema:StatsSchema,
    StockSchema:StockSchema,
};

then updated file1 and file2 as below

stats.js

 var mongoose     = require('mongoose');
    var logger   = require('../../util/log');

    var modelSchemas = require('../Schemas');
    var StatsSchema=modelSchemas.StatsSchema;
    var StockSchema=modelSchemas.StockSchema;
    Stock = mongoose.model('Stock', StockSchema);
    Stats = mongoose.model('Stats', StatsSchema);


    function createstats () {

        Stock.aggregate([

        .....
        .....
        ])
    }
    module.exports = mongoose.model('Stats', StatsSchema);

stock.js

var mongoose     = require('mongoose');    
    var logger   = require('../../util/log');

var modelSchemas = require('../Schemas');
var StatsSchema=modelSchemas.StatsSchema;
var StockSchema=modelSchemas.StockSchema;

Stock = mongoose.model('Stock', StockSchema);
Stats = mongoose.model('Stats', StatsSchema);

    function updateqty () {
        Stats.update(

        .....
        .....
        )
    }
    module.exports = mongoose.model('Stock', StockSchema);