multiple database structure by schema

f1_config.js

//database/config.js
const mongoose = require('mongoose');

class Database {
  constructor(options) {
    this.options = options;
    this.connect();
  }

  connect() {

    //Create the DSN address And Connect to the database
    mongoose.connect(this.options.dsn, {
      useNewUrlParser: true,
      useUnifiedTopology: true
    });
  }
}

module.exports = Database;

f2_users.js

//models/user.js
const mongoose = require('mongoose');
const Database = require('../database/config');

class User extends Database {
  constructor(options) {
    super(options);
    this.schema = new mongoose.Schema({
      name: String,
      email: String
    });
    this.model = mongoose.model('User', this.schema);
  }

  create(data) {
    // Create a new user
    const user = new this.model(data);
    return user.save();
  }

  find(query) {
    // Find users that match the query
    return this.model.find(query);
  }
}

module.exports = User;

f4_index.js

//test for express js you need to add this line in the router/index.js 
const user = new User({
  dsn: 'MONGO_URL' // this url can be come from session or cookie or environment. This is how to dynamically change dsn by schema
});
//
//DSN
//PROJECT

router.post('/create', (req, res) => {
user.dsn = req.dsn
projectFolder = "MM"
const User = require('../models/'+projectFolder+'/config');

  user
    .create(req.body)
    .then((data) => {
      res.json(data);
    })
    .catch((err) => {
      res.json(err);
    });
});