Mi código funciona perfectamente en localhost pero recibo un mensaje de error Cannot GET/ durante la implementación en Heroku Server.

mi código index.js

 const express = require('express') const app = express() const dotenv = require('dotenv').config() const bodyParser = require('body-parser') const port = process.env.PORT || 3000 app.use(express.json()) app.use(bodyParser.urlencoded({extended:true})) app.use(bodyParser.json()) const {dbConnection} = require('./connection/database') dbConnection() const routes = require('./route/routes') app.use('./route', routes) app.listen(process.env.PORT || 3000, ()=>{ console.log(`code is running on ${port}`) })

mi codigo de conexion

 const mongoose = require('mongoose') const dbConnection = async()=>{ try{ console.log('MongoDB Connected', process.env.DB_CONNECT) var mongoURI = "mongodb://mongo:27017/index.js" const conn = await mongoose.connect("mongodb://127.0.0.1:27017/welcome",{ useNewUrlParser: true, useUnifiedTopology: true }).then((conn)=>{ console.log(`mongoDB Connected : ${conn.connection.host}`) }) }catch (error){ console.log('error while connectingdb' + error) } } module.exports={dbConnection}