simple ajax request to localhost nodejs server

I wrote very simple server :

/* Creating server */
var server = http.createServer(function (request, response) {
  response.writeHead(200, {"Content-Type": "text/plain"});
  response.end("Hello World\n");
});

/*Start listening*/
server.listen(8000);

I run it using nodejs.

Now i want to write simple client that use ajax call to send request to server and print response (Hello World)

Here javascript of clinet:

$.ajax({
            type: "GET",
            url: "http://127.0.0.1:8000/" ,
            success: function (data) {
            console.log(data.toString);
            }
        });

When I open client html file i get following error in console:

XMLHttpRequest cannot load http://127.0.0.1:8000/. No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'null' is therefore not allowed access.

I tried adding to ajax call following:

 $.ajax({
            type: "GET",
            url: "http://127.0.0.1:8000/" ,
            dataType: 'jsonp',
            crossDomain: true,
            success: function (data) {
            console.log(data.toString);
            }
        });

But then i get 

Resource interpreted as Script but transferred with MIME type text/plain: "http://127.0.0.1:8000/?callback=jQuery211046317202714271843_1410340033163&_=1410340033164".

Anyone can explain what i did wrong and perhaps how to fix it?

Many thanks!

The first error is caused by CORS (Cross Origin Resource Sharing) policy. It's rule by all browsers that you cannot make a request to a remote server in AJAX other than to the current server the script/page was loaded from unless that remote server allows it via Access-Control-Allow-Origin header.

I suggest serving the page from the same Node.js server. Then it will work. Example, when the request comes to root / page, then serve the index.html file, otherwise, server whatever other content you want.

var http = require('http'),
    fs = require('fs');

/* Creating server */
var server = http.createServer(function (request, response) {
    if (request.url == '/' || request.url == '/index.html') {
        var fileStream = fs.createReadStream('./index.html');

        fileStream.pipe(response);
    } else {
        response.writeHead(200, {"Content-Type": "text/plain"});
        response.end("Hello World\n");
    }
});

/*Start listening*/
server.listen(8000);

To overcome the CORS, in your node.js file write the below, based on what you need:

// Website you wish to allow to connect
res.setHeader('Access-Control-Allow-Origin', '*');

// Request methods you wish to allow
res.setHeader('Access-Control-Allow-Methods', 'GET, POST, OPTIONS, PUT, PATCH, DELETE');

// Request headers you wish to allow
res.setHeader('Access-Control-Allow-Headers', 'X-Requested-With,content-type');

// Set to true if you need the website to include cookies in the requests sent
// to the API (e.g. in case you use sessions)
res.setHeader('Access-Control-Allow-Credentials', true);