How to include javascript on client side of node.js?

Question

I'm a beginner of node.js and javascript.

I want to include external javascript file in html code. Here is the html code, "index.html":

<script src="simple.js"></script>

And, here is the javascript code, "simple.js":

document.write('Hello');

When I open the "index.html" directly on a web browser(e.g. Google Chrome), It works. ("Hello" message should be displayed on the screen.)

However, when I tried to open the "index.html" via node.js http server, It doesn't work. Here is the node.js file, "app.js":

var app = require('http').createServer(handler)
  , fs = require('fs')

app.listen(8000);

function handler (req, res) {
  fs.readFile(__dirname + '/index.html',
  function (err, data) {
    if (err) {
      res.writeHead(500);
      return res.end('Error loading index.html');
    }

    res.writeHead(200);
    res.end(data);
  });
}

("index.html", "simple.js" and "app.js" are on same directory.) I started the http server. (by "bash$node app.js") After then, I tried to connect "localhost:8000". But, "Hello" message doesn't appear.

I think the "index.html" failed to include the "simple.js" on the http server.

How should I do?

Answer 1

Alxandr is right. I will try to clarify more his answer.

It happens that you have to write a "router" for your requests. Below it is a simple way to get it working. If you look forward www.nodebeginner.org you will find a way of build a proper router.

var fs = require("fs");
var http = require("http");
var url = require("url");

http.createServer(function (request, response) {

    var pathname = url.parse(request.url).pathname;
    console.log("Request for " + pathname + " received.");

    response.writeHead(200);

    if(pathname == "/") {
        html = fs.readFileSync("index.html", "utf8");
        response.write(html);
    } else if (pathname == "/script.js") {
        script = fs.readFileSync("script.js", "utf8");
        response.write(script);
    }


    response.end();
}).listen(8888);

console.log("Listening to server on 8888...");

Answer 2

function contentType(ext) {
    var ct;

    switch (ext) {
    case '.html':
        ct = 'text/html';
        break;
    case '.css':
        ct = 'text/css';
        break;
    case '.js':
        ct = 'text/javascript';
        break;
    default:
        ct = 'text/plain';
        break;
    }

    return {'Content-Type': ct};
}

var PATH = 'C:/Users/DELL P26E/node_modules'
var http = require("http");
var fs = require('fs');
var url = require("url");
var path = require("path")
var fileName = "D:/index.html";
    
var server = http.createServer (function (request, response) {

var dir = "D:/";
var uri = url.parse(request.url).pathname;

if (uri == "/") {
    uri = "index.html";
}

var filename = path.join(dir, uri);

fs.readFile(filename,
    function (err, data) {
        if (err) {
            response.writeHead(500);
            return response.end('Error loading index.html');
        }
                
        var ext = path.extname(filename)
        response.setHeader('content-type',contentType(ext));
        response.writeHead(200);
        response.end(data);
    });
}).listen(3000);
    
console.log('Server running on 8124') ;