javascript - export mongo database connection to models.js file -

app.js file:

var express = require('express'); var path = require('path'); var mongoose = require('mongoose'); var bodyparser = require('body-parser');   var conn = mongoose.createconnection('mongodb://localhost/database_name');  var app = express(); app.set('view engine','ejs'); app.set('views', path.join(__dirname, 'views'));  app.use(express.static(path.join(__dirname, 'public'))); app.use(bodyparser.urlencoded({extended:true}));  app.use(require('./routes/index')); app.use(require('./routes/page1')); app.use(require('./routes/page2')); app.use(require('./routes/page3')); app.use(require('./routes/page4'));  exports.conn = conn;  app.listen(3000,function(request, response){     console.log("server running @ port 3000"); }); 

models.js file:

var mongoose = require('mongoose'); var app = require('./app');  var conn = app.conn  module.exports.user = conn.model('user', new mongoose.schema({     username: string,     password: string, })); 

on running node app.js, getting error typeerror: cannot read property 'model' of undefined. app.js , models.js in same folder.

p.s. using createconnection function because have make 2 database connections.

you should not require app.js inside module. defeats purpose. either use separate module handles connection, or use dependency injection this:

models.js

var mongoose = require('mongoose');  module.exports = function(conn) { // inject connection     return {         user: conn.model('user', new mongoose.schema({             username: string,             password: string,         })     }; } 

app.js

var conn = mongoose.createconnection('mongodb://localhost/database_name');  var models = require('./models')(conn);  models.user(...) // stuff user function 

this better structured, more maintainable , better testable can inject mock conn.