Node.js Tutorial - Node.js HTTP Files

Serving Base HTML

The following section shows how we can create a simple web server that returns HTML files from a folder.

Create a simple HTML file, called index.html, that we plan to return on every request to GET '/' on the server.

 

   Hello there 
 

   You are looking lovely!

The following code shows how to serve static html file to the client.


var http = require('http'); 
var fs = require('fs'); 
//from w w w  . j  ava 2s. c o m
function send404(response) { 
    response.writeHead(404, { 'Content-Type': 'text/plain' }); 
    response.write('Error 404: Resource not found.'); 
    response.end(); 
} 

var server = http.createServer(function (req, res) { 
    if (req.method == 'GET' && req.url == '/') { 
        res.writeHead(200, { 'content-type': 'text/html' }); 
        fs.createReadStream('./public/index.html').pipe(res); 
    } else { 
        send404(res); 
    } 
}).listen(3000); 

console.log('server running on port 3000');

If you start the server (run node server.js ) and open your browser at http://localhost:3000, you will see the HTML page we created earlier.

Serving a Directory

First, create a simple client-side JavaScript file that appends to the body after HTML loading is complete.

We plan to request this JavaScript file from the server.

window.onload = function () { 
    document.body.innerHTML += 'Talk JavaScript with me'; 
}

Modify our simple HTML file by adding a script tag in the <head> to load a client-side JavaScript file

To support this JavaScript loading, we need to use the path module to resolve the path to the file on the file system based on the request.url property.

We also need to see if we have a MIME type registered for the file type requested.

We have to make sure the file exists before we try to read it from the file system.

Here is the source code for serving a folder to the client.


var http = require('http'); 
var fs = require('fs'); 
var path = require('path'); 
//  w  w  w.j a  va  2s.co  m
function send404(response) { 
    response.writeHead(404, { 'Content-Type': 'text/plain' }); 
    response.write('Error 404: Resource not found.'); 
    response.end(); 
} 

var mimeLookup = { 
    '.js': 'application/javascript', 
    '.html': 'text/html' 
}; 

var server = http.createServer(function (req, res) {
    if (req.method == 'GET') { 
         var fileurl; 
        if (req.url == '/') 
           fileurl = '/index.html'; 
        else 
           fileurl = req.url; 
        var filepath = path.resolve('./public' + fileurl); 

        var fileExt = path.extname(filepath); 
        var mimeType = mimeLookup[fileExt]; 
        if (!mimeType) { 
            send404(res); 
            return;
        }
        fs.exists(filepath, function (exists) {
            if (!exists) {
                send404(res); 
                return; 
            };
            res.writeHead(200, { 'content-type': mimeType }); 
            fs.createReadStream(filepath).pipe(res);
         }); 
     } else {
         send404(res);
     } 
}).listen(3000); 

console.log('server running on port 3000');