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Postman GET url request test for simple server API

I'm learning server-side javascript and am trying to test a GET request using postman where the server (server.js) receives a request for products.html (products.js) and returns the products JSON.
My files are packaged via npm, products.js is held in node_modules, and when I run server.js in command and then open localhost:3000 in browser, I can see that it's connecting. But, the browser returns a 404 and command shows a 400.
I feel like this is likely a syntax or file path error (or possibly I just don't know how to use postman), but I've been running myself in circles trying to fix. Anything stand out as wrong / any advice on how to correct?
//server.js
var fs = require('fs');
var http = require('http');
var url = require('url');
var product_mgr = require('product_manager'),
path=require('path');
//create server that listens on port 3000
http.createServer(function(req, res) {
var urlObj = url.parse(req.url, true, false);
var filename = urlObj.pathname;
fs.readFile(filename, function (err, data) {
// if url not returned, show error code 404
if (err) {
res.writeHead(404, {'Content-Type': 'application/json'});
return res.end("404 Not Found");
} else {
// if url returned, show success code 200
res.writeHead(200, {'Content-Type': 'application/json'});
res.write(data);
return res.end();
}});
}).listen(3000, function() {
console.log('Listening on port 3000.');
});
//products.js
//create class that represents a product
//include name, price, description and qty
class Product {
constructor(name, price, description, qty) {
this.name = name;
this.price = price;
this.description = description;
this.qty = qty;
};
};
var product_1 = new Product('Yo Yo', 2.99, 'Spinning Toy', 40);
var product_2 = new Product('Hot Wheel', 1.99, 'Tiny Toy Car', 30);
var product_3 = new Product('Glove', 23.49, 'Baseball Glove', 12);
var productArray = [product_1, product_2, product_3];
//create function called products which returns JSON array of product info
function products() {
return JSON.stringify(productArray)
};
//export products function
exports.products = products;

var fs = require('fs');
var http = require('http');
var url = require('url');
var product_mgr = require('product_manager');
http.createServer(function(req, res) {
var urlObj = url.parse(req.url, true, false);
var filename = "." + urlObj.pathname;
if (req.method == "GET" && req.url == "/products.html") {
res.writeHead(200, {
'Content-Type': 'application/json'
});
res.end(JSON.stringify({
error: null
}));
} else {
res.writeHead(404, {
'Content-Type': 'application/json'
});
res.end(JSON.stringify({
error: "Invalid Request"
}));
}
}).listen(3000, function() {
console.log('Listening on port 3000.');
});

unable to create simple websocket - NodeJS

I am trying to follow this tutorial: https://www.simonewebdesign.it/101-web-socket-protocol-handshake/ for developing simple websocket protocol.
I am visiting localhost:1337/index.html but I get:
This localhost page can’t be found
No web page was found for the web address: http://localhost:1337/index.html
Search Google for localhost 1337 index
HTTP ERROR 404
if I visit this url: file:///C:/Users/.../websocket-demo/index.html
I atleast see the index.html page being rendered. But in console I get this error:
WebSocket connection to 'ws://localhost:1337/' failed: Error in connection establishment: net::ERR_CONNECTION_REFUSED
I am not sure what's wrong?
I have 3 files: index.html, server.js and client.js
server.js
#!/usr/bin/env node
var WebSocketServer = require('websocket').server;
var http = require('http');
var server = http.createServer(function(request, response) {
console.log('Received request from ' + request.url);
response.writeHead(404);
response.end();
});
server.listen(1337, function() {
console.log('Server is listening on port 1337.');
});
wsServer = new WebSocketServer({
httpServer: server,
autoAcceptConnections: false // because security matters
});
function isAllowedOrigin(origin) {
console.log('Connection requested from origin ' + origin);
valid_origins = [
'http://localhost:8080',
'127.0.0.1',
'null'
];
if (valid_origins.indexOf(origin) != -1) {
console.log('Connection accepted from origin ' + origin);
return true;
}
console.log('Origin ' + origin + ' is not allowed.')
return false;
}
wsServer.on('connection', function(webSocketConnection) {
console.log('Connection started.');
});
wsServer.on('request', function(request) {
var connection = isAllowedOrigin(request.origin) ?
request.accept('echo-protocol', request.origin)
: request.reject();
connection.on('message', function(message) {
var response = '';
console.log('Received Message: ' + message.utf8Data);
if (message.type === 'utf8') {
switch (message.utf8Data) {
case 'hi':
response = 'Hey there';
break;
case 'hello':
response = 'Heya!';
break;
case 'xyzzy':
response = 'Nothing happens.';
break;
case 'desu':
response = 'Keep typing, man. Keep typing.';
break;
default:
response = "Hello. Uh... what am I supposed to do with '" +
message.utf8Data + "'?";
}
connection.sendUTF(response);
}
});
connection.on('close', function(reasonCode, description) {
console.log(connection.remoteAddress + ' has been disconnected.');
});
});
client.js
(function () {
var ws = new WebSocket('ws://localhost:1337', 'echo-protocol');
ws.onopen = function (event) {
console.log('Connection opened.');
}
ws.onmessage = function (event) {
console.log('Response from server: ' + event.data);
}
ws.onclose = function (event) {
console.log('Connection closed.');
}
ws.onerror = function (event) {
console.log('An error occurred. Sorry for that.');
}
WebSocket.prototype.sendMessage = function (message) {
this.send(message);
console.log('Message sent: ' + message);
}
document.getElementById('send').addEventListener('click', function (event) {
event.preventDefault();
var message = document.getElementById('message').value;
ws.sendMessage(message);
});
})();
index.html - consist of forms
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>WebSocket Client Demo</title>
</head>
<body>
<h1>WebSocket Client</h1>
<form>
<label for="message">Send a message</label>
<input id="message" name="message" type="text">
<button id="send" name="send">Send</button>
</form>
<script src="client.js"></script>
</body>
</html>

Your web server doesn't serve your index.html file.
You can see this post to get an idea how to serve static files, or you can just boot up another HTTP server to serve your index file, like with python, the way they suggested in the README file of the tutorial that you are following: https://github.com/simonewebdesign/websocket-demo

How to post data from my html page to a listener?

I'm currently designing a UI for an Automated Parking System. I currently need to test if my page sends out data from a form by sending it to a listener. I currently have this code but I'm not sure why it isn't working. Any help would be greatly appreciated.
This is my code that sends the data to a local listener.
<script>
var INPARK = {cardID: $("#ticket_num").val(), lift: 1, floor: 1};
$.ajax({
type:"POST",
url: '192.168.150.148:5007',
contentType:"application/json",
data: JSON.stringify(INPARK)
});
</script>
This is the listener code.
var HOST = '192.168.150.148'; // This should be your IP of 192.168.150.XXX
var PORT = 5007;
var http = require('http');
http.createServer(function (req, res) {
// Only listen for POST requests
if (req.method === 'POST') {
var buffer = '';
req.on('data', function (chunk) {
buffer += chunk;
});
req.on('end', function () {
var path = req.url.substring(0, req.url.indexOf('/', 1)).toUpperCase();
var json;
try {
json = JSON.parse(buffer);
} catch (err) {
//
}
if (path === '/INPARK') {
// Handle INPARK request
console.log(json);
res.write('inpark results');
} else if (path === '/OUTPARK') {
// Handle OUTPARK request
console.log(json);
res.write('outpark results');
} else {
// Do nothing - Bad request
res.write('BAD REQUEST');
}
// Close the connection
res.end();
});
}
}).listen(PORT, HOST, function () {
console.log('Listening at %s:%s', HOST, PORT);
});

Your ajax request is most likely going from port 80 or 443 to 5007, which is a cross domain request, hence it will fail,
If you want to resolve this issue, read up on CORS:
https://en.wikipedia.org/wiki/Cross-origin_resource_sharing,
and JSONP:
https://en.wikipedia.org/wiki/JSONP

node.js / jQuery cross domain: ERR_CONNECTION_REFUSED

I'm new to Node.js.
I'm creating a simple node/express application that serves a single web page containing one button that when clicked makes a jQuery ajax request to an Express route.
The route callback makes an http.get request to openexchangerates.org for some json data containing foreign exchange rates. The JSON is then output to the Developer Tools console window.
The application works on the first button click, but on any subsequent clicks the console window displays:
GET http://127.0.0.1:3000/getFx net::ERR_CONNECTION_REFUSED
A screen grab of the Developer Tools console window shows the result of the first click, and then the second click when the connection is refused.
The error detail is as follows:
GET http://127.0.0.1:3000/getFx net::ERR_CONNECTION_REFUSED jquery-2.1.3.min.js:4
n.ajaxTransport.k.cors.a.crossDomain.send jquery-2.1.3.min.js:4
n.extend.ajax (index):18
(anonymous function) jquery-2.1.3.min.js:3
n.event.dispatch jquery-2.1.3.min.js:3
n.event.add.r.handle
My simple Node/Express application is as follows:
var express = require('express');
var app = express();
var http = require("http");
var data = "";
var json;
console.log( "__dirname", __dirname );
app.use( express.static( __dirname + '/') );
var options = {
host:"openexchangerates.org",
path:"/api/latest.json?app_id=<get free ID from openexchangerates.org>"
};
app.get("/", function( req, res ) {
res.sendFile('index.html', { root: __dirname });
})
app.get("/getfx", function(req, res) {
console.log("Route: getFx");
getFx(res);
})
function getFx(res) {
console.log("http getFx");
http.get(options, function (response) {
response.on("data", function (chunk) {
//console.log("data:\n"+chunk);
data += chunk;
});
response.on("end", function () {
json = JSON.parse(data);
console.log("http response end:");
res.end( data );
});
response.on("error", function (e) {
console.log("error:\n" + e.message);
});
})
}
app.listen(3000);
My html index page is:
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title>Get FX</title>
<script src="http://code.jquery.com/jquery-2.1.3.min.js"></script>
<script>
$(document).ready(function() {
console.log( "document ready");
$("#btnFx").click(function() {
console.log('clicked', this );
$.ajax({
url : "http://127.0.0.1:3000/getFx",
dataType : "json",
success : function(json) {
console.log("json returned:\n", json);
}
});
} );
})
</script>
</head>
<body>
<button id="btnFx" style="width:200px">Get foreign exchange rates</button>
</body>
For openexchangerates.org to serve the data, a free app id is required. Anyone able to help resolve this may have to go through their very short sign up:
That link is here:
https://openexchangerates.org/signup/free
However it's possible that my mistake is glowingly obvious to those with better Node/Express/jQuery knowledge.
Many thanks in advance

The way you defined your data and json vars is causing subsequent requests to fail. Since you defined them up front, all requests will re-use them, meaning by the time you JSON.parse data for the second request, data will contain two valid json strings, thus making one invalid json string. To fix this, define data and json farther down in the callback.
var express = require('express');
var app = express();
var http = require("http");
//var data = "";
//var json;
console.log( "__dirname", __dirname );
app.use( express.static( __dirname + '/') );
var options = {
host:"openexchangerates.org",
path:"/api/latest.json?app_id=<get free ID from openexchangerates.org>"
};
app.get("/", function( req, res ) {
res.sendFile('index.html', { root: __dirname });
})
app.get("/getfx", function(req, res) {
console.log("Route: getFx");
getFx(res);
})
function getFx(res) {
console.log("http getFx");
http.get(options, function (response) {
var data = "";
var json;
response.on("data", function (chunk) {
//console.log("data:\n"+chunk);
data += chunk;
});
response.on("end", function () {
console.log("http response end:");
json = JSON.parse(data);
res.json(json);
});
response.on("error", function (e) {
console.log("error:\n" + e.message);
});
})
}
app.listen(3000);

Issue comes from Cross origin requests protection which happens on localhost with chrome. Try to use other browser or just Allow origin to all hosts (*) or your host (http://localhost:3000):
app.use( express.static( __dirname + '/') );
app.use(function(req,res,next){
res.header('Access-Control-Allow-Origin', '*');
res.header('Access-Control-Allow-Methods', 'GET,PUT,POST,DELETE,OPTIONS');
res.header('Access-Control-Allow-Headers', 'Content-Type, Authorization, Content-Length, X-Requested-With');
// intercept OPTIONS method
if ('OPTIONS' == req.method) {
res.send(200);
}
else {
next();
}
});

io.connect: io is not defined but socket.io is loaded

I have built a node.js server that provides a client.html page with a list of messages from a mysql db. I can't make it work using an ajax call.
The client.html page is this:
<time></time>
<div id="container">Loading ...</div>
<script src="http://oclock.dyndns.org:8000/socket.io/socket.io.js"></script>
<!--<script src="socket.io/socket.io.js"></script>-->
<script src="http://code.jquery.com/jquery-latest.min.js"></script>
<script>
// create a new websocket
var socket = io.connect('http://oclock.dyndns.org:8000');
// on message received we print all the data inside the #container div
socket.on('notification', function (data) {
var msgs = '<div>';
$.each(data.flashmsgs,function(index,flashmsg){
msgs += "<b>Messaggio inviato da " + flashmsg.created_by + "</b><br>";
msgs += flashmsg.testo;
});
msgs += '</div>';
$('#container').html(msgs);
$('time').html('Last Update:' + data.time);
});
</script>
and the code for the ajax call is the following:
(function nodeLoader(){
$.ajax({
url: "client.html",
method: "get",
data: {hk: hk },
success: function(data){
$('#messaggi').html(data);
}
});
})();
The socket.io code is loaded but I get an error on io.connect: io is not defined. Same issue if i change the url from client.html to http://oclock.dyndns.org:8000 (the url of the node.js server that is listening for requests).
Any help is appreciated!
EDIT:
server.js
var hwkey;
var app = require('http').createServer(handler),
io = require('socket.io').listen(app),
url = require('url'),
fs = require('fs'),
mysql = require('mysql'),
connectionsArray = [],
connection = mysql.createConnection({
host: 'localhost',
user: 'root',
password: 'flipper',
database: 'oclock',
port: 3306
}),
POLLING_INTERVAL = 3000,
pollingTimer;
// If there is an error connecting to the database
connection.connect(function(err) {
// connected! (unless `err` is set)
if (err) {
console.log(err);
}
});
// creating the server ( localhost:8000 )
app.listen(8000);
function handler(req, res) {
var origin = (req.headers.origin || "*");
if (req.method.toUpperCase() === "OPTIONS"){
res.writeHead(
"204",
"No Content",
{
"access-control-allow-origin": origin,
"access-control-allow-methods": "GET, POST, PUT, DELETE, OPTIONS",
"access-control-allow-headers": "content-type, accept",
"access-control-max-age": 10, // Seconds.
"content-length": 0
}
);
return( res.end() );
}
console.log("INCOMING REQUEST: "+req.method+" "+req.url);
req.parsed_url = url.parse(req.url, true);
var getp = req.parsed_url.query;
hwkey = getp.hk;
fs.readFile(__dirname + '/client.html', function(err, data) {
if (err) {
console.log(err);
res.writeHead(500);
return res.end('Error loading client.html');
}
res.writeHead(
200,
{
"access-control-allow-origin": origin,
"content-length": data.length
}
);
res.end(data);
});
}
function pollingLoop(){
// Doing the database query
var query = connection.query('SELECT id, testo, created_by FROM flashmsgs WHERE hwk="'+hwkey+'" AND letto="0"'),
//var query = connection.query('SELECT max(id), testo, created_by FROM flashmsgs'),
flashmsgs = []; // this array will contain the result of our db query
// setting the query listeners
query
.on('error', function(err) {
// Handle error, and 'end' event will be emitted after this as well
console.log(err);
updateSockets(err);
})
.on('result', function(flashmsg) {
// it fills our array looping on each user row inside the db
flashmsgs.push(flashmsg);
})
.on('end', function() {
// loop on itself only if there are sockets still connected
if (connectionsArray.length) {
pollingTimer = setTimeout(pollingLoop, POLLING_INTERVAL);
updateSockets({
flashmsgs: flashmsgs
});
} else {
console.log('The server timer was stopped because there are no more socket connections on the app')
}
});
};
// creating a new websocket to keep the content updated without any AJAX request
io.sockets.on('connection', function(socket) {
console.log('Number of connections:' + connectionsArray.length);
// starting the loop only if at least there is one user connected
if (!connectionsArray.length) {
pollingLoop();
}
socket.on('disconnect', function() {
var socketIndex = connectionsArray.indexOf(socket);
console.log('socketID = %s got disconnected', socketIndex);
if (~socketIndex) {
connectionsArray.splice(socketIndex, 1);
}
});
console.log('A new socket is connected!');
connectionsArray.push(socket);
});
var updateSockets = function(data) {
// adding the time of the last update
data.time = new Date();
console.log('Pushing new data to the clients connected ( connections amount = %s ) - %s', connectionsArray.length , data.time);
console.log(hwkey);
// sending new data to all the sockets connected
connectionsArray.forEach(function(tmpSocket) {
tmpSocket.volatile.emit('notification', data);
});
};
console.log('Please use your browser to navigate to http://localhost:8000');

Okay, I misunderstood at first. I just investigated your live app and it appears your ajax call is pulling down an entire html document.
If you're loading markup via ajax and then inserting into the existing page, you don't want a full HTML document. Just send down the body content.
Also, the socket.io script reference should ideally be on the parent page, not the page loaded via ajax.