Node.js Introduction

A brief introduction to Node.js given at the Grand Rapids Web Development Group.

Transcript

1. INTRODUCTION
2. Hi, I’m @bkeepers
4. nodejs.org Node.js is a platform built on Chrome's JavaScript runtime for easily building fast, scalable network applications. Node.js uses an event-driven, non- blocking I/O model that makes it lightweight and efficient, perfect for data-intensive real-time applications that run across distributed devices.
5. server side JavaScript
6. $ node webserver.js var http = require('http'), server = http.createServer(); server.on('request', function (req, res) { res.writeHead(200, {'Content-Type': 'text/plain'}); res.end('Hello World\n'); }); server.listen(1337, "127.0.0.1"); console.log('Server running at http://127.0.0.1:1337/'); webserver.js
8. event loop modules package management
9. non-blocking evented I/O
10. event driven
11. event driven Button
12. event driven Button
13. event driven Button $('button').on('click', function(event) { alert('Event Driven!') });
14. event driven server.on('request', function(req, res) { res.write(handleRequest(req)) });
15. non-blocking
17. // blocking var files = fs.readdirSync('/tmp') for(var i = 0; i < files.length; i++) { var file = files[i]; fs.unlinkSync('/tmp/' + file); console.log('successfully deleted ' + file); }
18. // blocking var files = fs.readdirSync('/tmp') for(var i = 0; i < files.length; i++) { var file = files[i]; fs.unlinkSync('/tmp/' + file); console.log('successfully deleted ' + file); } // non-blocking fs.readdir('/tmp', function(err, files) { for(var i = 0; i < files.length; i++) { var file = files[i]; fs.unlink('/tmp/' + file, function (err) { if (err) throw err; console.log('successfully deleted ' + file); }); } });
19. CommonJS modules
20. JavaScript Pollutes
21. JavaScript Pollutes string = "pollution";
23. var http = require('http');
24. hello.js module.exports = function() { return 'Hello World' };
25. $ node myapp.js myapp.js var hello = require('./hello.js'); console.log(hello());
26. package management
27. npmjs.org
28. $ npm install <package>
29. package.json
30. package.json $ npm install { "name": "myapp", "version": "0.0.1", "dependencies": { "socket.io": "0.8.7", "coffee-script": "1.2.0", "spine": "~1.0.5" } }
31. building the simplest chat app in the world demo
32. references
33. http://nodejs.org/api/
35. thanks! @bkeepers