ExpressJS not call ajax get method - node.js

Question

I created a sample ExpressJS App by using Express Application Generator
I want to call localhost:3000/data to get some data. I added these code to app.js:
app.get('/data', function(req, res){
debug("get data");
});
Also I make ajax request in client side js file :
$.ajax({
url: 'http://localhost:3000/data/',
//url: 'http://localhost:3000/data', -> also not work
type:'GET',
dataType: 'json',
success: (data) => {
console.log("get data from client js", data);
}
});
but my app.get method never call. GET /data/ 404 written in console screen. Also when I typed http://localhost:3000/data on browser I got Not Found error. how can I fix this ?
my www file :
#!/usr/bin/env node
/**
* Module dependencies.
*/
var app = require('../app');
var debug = require('debug')('myapp:server');
var http = require('http');
/**
* Get port from environment and store in Express.
*/
var port = normalizePort(process.env.PORT || '3000');
app.set('port', port);
/**
* Create HTTP server.
*/
var server = http.createServer(app);
/**
* Listen on provided port, on all network interfaces.
*/
server.listen(port);
server.on('error', onError);
server.on('listening', onListening);
/**
* Normalize a port into a number, string, or false.
*/
function normalizePort(val) {
var port = parseInt(val, 10);
if (isNaN(port)) {
// named pipe
return val;
}
if (port >= 0) {
// port number
return port;
}
return false;
}
/**
* Event listener for HTTP server "error" event.
*/
function onError(error) {
if (error.syscall !== 'listen') {
throw error;
}
var bind = typeof port === 'string'
? 'Pipe ' + port
: 'Port ' + port;
// handle specific listen errors with friendly messages
switch (error.code) {
case 'EACCES':
console.error(bind + ' requires elevated privileges');
process.exit(1);
break;
case 'EADDRINUSE':
console.error(bind + ' is already in use');
process.exit(1);
break;
default:
throw error;
}
}
/**
* Event listener for HTTP server "listening" event.
*/
function onListening() {
var addr = server.address();
var bind = typeof addr === 'string'
? 'pipe ' + addr
: 'port ' + addr.port;
debug('Listening on ' + bind);
}

Answer 1

I'm not exactly sure where your problem lies because there isn't enough code displayed to determine that. instead I have written a simple express server for you to use:
const express = require('express');
const bodyParser = require('body-parser');
const CORS = require('cors');
const app = express();
app.use(bodyParser.json());
app.use(CORS());
app.get('/data', (req, res) => {
res.json({message: "working"});
});
app.listen(5000, () => {
console.log('Server listening on port 5000');
});