Mongoose Schema [Object] issue

Question

I am using Nodejs connected via mongoose to mongoDB. Need to apply below working aggregation logic in Nodejs(Mongoose). Aggregation is working properly in DB side , but i am getting [Object] error .

Model1 :getAllUsers

Here i am not sure whether my Model creation is correct or not.

  var mongoose = require('mongoose');
    const getAllUsersDataSchema = new mongoose.Schema({
        
        userRefID:String ,
        userName:String,
        divisionId: String,
        divisionName:String,
        emailId :String,
//This role definition i created only for aggregation to work
        role:[{        
            userRefID:String,
            skillRefId:String,
            queueName:String,
           
        }]
    })
    module.exports = getAllUsers = mongoose.model('getAllUsers',getAllUsersDataSchema );

Model2 :getAllUsersRoles

var mongoose = require('mongoose');
const getAllUsersRolesDataSchema = new mongoose.Schema({   
    userRefID:String ,
    skillRefId: String,
    queueName:String,

})
module.exports = getAllUsersRoles = mongoose.model('getAllUsersRoles',getAllUsersRolesDataSchema);

Working Aggregation query in DB:

     db.getallusers.aggregate([
...   {
...     "$lookup": {
...       "from": "getallusersroles",
...       "localField": "userRefID",
...       "foreignField": "userRefID",
...       "as": "role"
...     }
...   }
... ]).pretty()
{
        "_id" : ObjectId("5ff2b73d2af2b806685735a4"),
        "userRefID" : "07f426ff-506f-4e5e-afdb-2c7397edac61",
        "userName" : "EPS Purecloud Support",
        "divisionId" : "36852a81-ad7f-4c71-a1cd-7f431c05179f",
        "divisionName" : "",
        "emailId" : "eps@genesys.com",
        "role" : [
                {
                        "_id" : ObjectId("5ff2b73c2af2b8066857355f"),
                        "userRefID" : "07f426ff-506f-4e5e-afdb-2c7397edac61",
                        "skillRefId" : "c02dbb03-ed78-442a-a9cd-0f16c823646b",
                        "queueName" : "CIM_test",
                        "__v" : 0
                },
                {
                        "_id" : ObjectId("5ff2b73c2af2b80668573560"),
                        "userRefID" : "07f426ff-506f-4e5e-afdb-2c7397edac61",
                        "skillRefId" : "a626d99e-f5e9-47ab-a5d0-d493003c737f",
                        "queueName" : "CLAIMS",
                        "__v" : 0
                },       
               
        ],
        "__v" : 0
}

Nodejs Code:

const express = require('express');
const router = express.Router();
const request = require('request');
const config = require('../config');
const fs = require('fs'); 
const getAllUsers = require ('../db/getAllUsersListmodel');
const getAllUsersRoles = require ('../db/getetUserRolesListModel');
var mongoose = require('mongoose');
mongoose.connect ('mongodb://localhost/testdb',{ useUnifiedTopology: true , useNewUrlParser: true });

router.get('/', (req, res) => {
   getAllUsers.aggregate([
      {
        "$lookup": {
          "from": "getallusersroles",
          "localField": "userRefID",
          "foreignField": "userRefID",
          "as": "role"
        }
      },
    
    ],(err,res)=>{
      console.log(res);
     
  })

});
  module.exports = router;

Console Output error:

 [
      {
        _id: 5ff2b73d2af2b806685735a4,
        userRefID: '07f426ff-506f-4e5e-afdb-2c7397edac61',
        userName: 'EPS Purecloud Support',
        divisionId: '36852a81-ad7f-4c71-a1cd-7f431c05179f',
        divisionName: '',
        emailId: 'eps@genesys.com',
        role: [ [Object], [Object] ],
        __v: 0
      },
    ]

Answer 1

As much as I can understand from your code:

This is the User model:

const mongoose = require('mongoose');
const Schema = mongoose.Schema;

const UserSchema = new Schema({
    userName: {
        type: String,
    },
    divisionId: {
        type: Schema.Types.ObjectId,
    },
    divisionName: {
        type: String,
    },
    emailId: {
        type: Schema.Types.ObjectId,
    },
});

module.exports = getAllUsers = mongoose.model('User', UserSchema);

This is the Role model:

const mongoose = require('mongoose');
const Schema = mongoose.Schema

const RoleSchema = new Schema({   
    userRefID: {
        type: Schema.Types.ObjectId,
    },
    skillRefId: {
        type: Schema.Types.ObjectId,
    },
    queueName: {
        type: String,
    },
});

module.exports = getAllUsersRoles = mongoose.model('Role', RoleSchema);

Aggregation method in action:

User.aggregate([
    {
      $lookup: {
        "from": "Role",
        "localField": "_id",
        "foreignField": "userRefID",
        "as": "roles"
      },
    },
]);

Please try this with your database full data.

Also consider using mongoose.populate to retrieve the result of user roles: https://mongoosejs.com/docs/populate.html