gfnork node.js workshop Lesson #3 node.js basics

first steps, modules, npm, Events

Transcript

8. 8 node > console.log('Hello World'); Hello World
9. 9 console.log('Hello World'); >node app.js Hello World
10. 10 var http = require('http'); http.createServer(function (req, res) { res.writeHead(200, { 'Content-Type': 'text/plain' }); res.end('Hello World\n'); }).listen(1337, '127.0.0.1'); console.log('Server running at http://127.0.0.1:1337/');
11. 11 var http = require('http'); http.createServer(function (req, res) { res.writeHead(200, { 'Content-Type': 'text/plain' }); res.end('Hello World\n'); }).listen(1337, '127.0.0.1'); console.log('Server running at http://127.0.0.1:1337/');
13. 13 exports.helloworld = function () { console.log('Hello World'); } var test = require('./test.js'); test.helloworld();
14. 14 module.exports = function () { this.name = "test object"; this.color = "red"; this.size = "large"; } var test = require('./test.js'); var testObject = new test(); console.log('name:' + testObject.name); console.log('color:' + testObject.color); console.log('size:' + testObject.size);
17. 17 { "name": "TestNodejsApp", "version": "0.0.0", "description": "TestNodejsApp", "private": true, "main": "app.js", "author": { "name": "Qiong Wu", "email": "" }, "dependencies": { "express": "3.4.4", "jade": "*", "stylus": "*" } }
20. 20 server.on('connection', function (stream) { console.log('someone connected!'); }); server.once('connection', function (stream) { console.log('Ah, we have our first user!'); });
21. 21 function Test(colour) { this.colour = colour; events.EventEmitter.call(this); this.sendEvent = function() { this.emit('EventSent'); } } Test.prototype.__proto__ = events.EventEmitter.prototype; var testObject = new Test('white'); testObject.on('EventSent', function() { console.log('Event received'); }); testObject.sendEvent();
23. 23 // write 'hello, ' and then end with 'world!' http.createServer(function (req, res) { res.write('hello, '); res.end('world!'); // writing more now is not allowed! });