How to create modules for Node.js?

Question

I have a simple code:

var http = require("http");  var server = http.createServer(function(request, response) {     response.writeHead(200, {"Content-Type" : "text/html"});     response.write("Hello World");     response.end(); });  server.listen(8000);  console.log("Server has started."); 

I would like to put this code into server.js. This code has to be a MODULE that has many internal functions. I would like to create server module and listen() function inside it.

I should put createServer() inside a function called listen().

If I have index.js how can I call this module and then do something like server.listen()?

Answer 1

The common pattern for nodejs modules is to create a file (e.g. mymodule.js) so:

var myFunc = function() {    ... };  exports.myFunc = myFunc; 

If you store this in the directory node_modules it can be imported thus:

var mymodule = require('mymodule');  mymodule.myFunc(args...); 

So, in your case, your module server.js could look like this:

// server.js var http = require("http");  var listen = function(port) {     var server = http.createServer(function(request, response) {         response.writeHead(200, {"Content-Type" : "text/html"});         response.write("Hello World");         response.end();     });     server.listen(port); };  exports.listen = listen; 

which would be invoked:

// client.js var server = require('server'); server.listen(8000);