This document provides an overview of Node.js, an asynchronous JavaScript runtime environment for building scalable network applications. It discusses how to install and use Node.js, common core modules for processes, filesystem, and networking, frameworks like Express, streams, load balancing, competitors like Tornado and Twisted, and references further resources.

1. Node.js (Advanced)
Suresh Reddy
Senior Software Engineer
Echidna, Inc.

2. Agenda

What is Node.JS

Using Node.JS

Common Modules

Streams

Express

Load balancing

Competitors

References

3. What is Node.JS

JavaScript programming environment for creating highly
scalable network programs

Provides evented, Non-blocking I/O

Built on top of V8
Node.JS is bare bone and the community are making stuff
like Express, connect etc.

4. What is Node.JS
Event driven programming
$.ajax(
url:'http://example.com/getProducts?cid=132867',
type:'GET',
contentType:'application/json',
success:function(response){// doWithResponse
},
error:function(xhr){// Error :(
}
);

5. Using Node.JS

Install Node.JS

wget http://nodejs.org/dist/node-v0.1.96.tar.gz

gunzip node-v0.1.96.tar.gz

cd node

./configure

make

make install

NPM

Install/Publish other modules you want by doing

npm install <module_name>

npm publish <module_name>

6. Node.JS – as an interactive shell
Similar to Python’s shell
$> node
>3+1
4
> true != false
true
>.help
>.exit

7. Node.JS – As a server
var http = require('http');
http.createServer(function (req, res) {
res.writeHead(200, {
'Content-Type': 'text/plain'
});
res.end('Hello Worldn');
}).listen(1337, "127.0.0.1");
console.log('Server running at
127.0.0.1:1337');

8. Core Modules

Processes

Filesystem

Networking

Utilities
The entire list can be found at http://nodejs.org/api/

9. Core Modules - Processes
Node allows you to analyze your process and manage external
process
Available Modules

process

child_process

10. Core Modules - Filesystem
Low level API to manipulate files
Available Modules

fs

path

11. Core Modules - Networking
Available Modules

net

dgram

http

tls

https

dns

12. Express

Basic web framework

Runs on top of Node.js

Provides routing and redirection helpers

Dynamic view helpers

Has support for session

Focus on high performance

13. Hello World Express App

14. Streams

Stream instances are Unix pipes

Readable

must emit ”data” events whenever they have data to be
read and ”end” when the data stream is finished.

Writable

must implement the write() method to accept new data
chunks into the stream and the end() method to instruct
the stream that the data is finished.

15. Node.JS is useful for..

Writing highly concurrent server applications

Sharing application logic between server and client

Peer-to-peer web applications using websockets

Real-time applications

16. Load Balancing
The ability to distribute work load across multiple servers

HAProxy

Nginix

Apache Http server

17. Other Asynchronous JavaScript
platforms

Tornado and Twisted for Python

Perl Object Environment for Perl

libevent for C

Vert.x for Java

EventMachine for Ruby

vibe.d for D

18. Links

http://nodejs.org

http://npmjs.org

http://expressjs.com

http://socket.io

19. Thank you