The document is a presentation about Node.js that discusses what problem it helps solve, its use of event-driven and non-blocking I/O, common use cases, industry support and examples of usage, how to code in Node.js including modules and frameworks, and how to scale Node.js applications. The presentation was given by Ovidiu Dimulescu at the Jax CodeCamp in October 2012.

1. Node.js, toy or power tool?
Jax CodeCamp, Oct 2012
Ovidiu Dimulescu
Saturday, October 6, 12

2. Agenda
• What problem?
• How’s Node.js helping?
• Use cases
• Industry support
• Coding in Node.js
• Ecosystem
• Q &A
Saturday, October 6, 12

3. About @odimulescu
• Working on the Web since 1997
• Into startup and engineering cultures
• Speaker at user groups
• Organizer for JaxMUG.com
• Co-Organizer for Jax Big Data meetup
Saturday, October 6, 12

4. Node.js - What’s the problem?
Fast CPUs Spinning wheels
How do we saturate the CPU doing useful work?
Saturday, October 6, 12

5. Node.js - How’s it helping?
• Uses event-driven, non-blocking IO
• Enforces async throughout*
Saturday, October 6, 12

6. Multi-Threaded Servers
*Credit: blog.cloudfoundry.com
Saturday, October 6, 12

7. Node.js - Single Thread, Event-ed
*Credit: blog.cloudfoundry.com
Saturday, October 6, 12

8. Node.js - Concurrency
Node.js Event Loop
Rq1 Rq1
Rq2 Rq2
Green - Request Executing
Red - IO wait
Saturday, October 6, 12

9. Node.js - Concurrency
Thread
Node.js
Higher Concurrency
Same Latency
Saturday, October 6, 12

10. Node.js - Been there, done that
Event Machines
• - Twisted
• - EventMachine
• - Mina, Netty, Atmosphere, vertx.io
• - POE
Others
• Erlang
• Scala / Akka
Saturday, October 6, 12

11. Node.js - But ...
They mix async with sync and the mentality is
towards sync in libraries, drivers etc.
Saturday, October 6, 12

12. Node.js - Use Cases
• Proxy between different data layers
• Soft real-time apps
• Crawlers
• CLI tools
• Quick prototyping
• Lower HW and Operational cost*
Saturday, October 6, 12

13. Node.js - Not best fit
• Culture mismatch
• Uses Javascript
• Requests are CPU intensive
• Apps relies on specific libraries / functionality
• Transactional systems
Saturday, October 6, 12

14. Node.js - Industry Support
Saturday, October 6, 12

15. Node.js - Industry Usage
Saturday, October 6, 12

16. Node.js - Installation
1. Go to nodejs.org
2. Download and run installer
Saturday, October 6, 12

17. Node.js - Installation
1. Go to nodejs.org
2. Download and run installer
What’s included?
node - binary
npm - cli package manager
built-in support for http, net, dns
Saturday, October 6, 12

18. Node.js - Server Installation
1. Regular Installation
2. Make it a service
Windows - NSSM, srvany, etc.
Unix - Distro dependent
3. Front-end WS Integration
IIS 7+ Integration - iisnode
Apache - mod_proxy or mod_rewrite
Nginx - rewrite or proxy
HAProxy, stunnel
Saturday, October 6, 12

19. Node.js - Considerations
Lowest privileges
Unix: drop to non-root via setuid / setguid
Front with a secure Proxy
Enable safeguards
“use strict”
Saturday, October 6, 12

20. Node.js - Hello World
CLI Version - helloworld.js
console.log(“Hello world”);
$ node helloworld.js
Hello World
Web Version
Saturday, October 6, 12

21. Node.js - Hello World
Web - Router Version
Saturday, October 6, 12

22. Node.js - I will call you back
Saturday, October 6, 12

23. Node.js - When, then
Saturday, October 6, 12

24. Node.js - Flow libraries
Serial independent
Runs a series of functions one after the previous function completed
Serial dependent
Runs a series of functions passing previous results into next function
Parallel fashion
Runs a series of function in parallel
Queue
Runs a series of function in parallel up to desired concurrency
Library Choices
Async, Groupie, Step, Q, etc.
Saturday, October 6, 12

25. Node.js - Modules
Module - mymodule.js
Client mymodule_client.js
Saturday, October 6, 12

26. Node.js - Modules
package.json
require(‘mylib’) - Lookup order
1. package.json -> ./lib/mylib.js
2. index.js
3. index.node
Saturday, October 6, 12

27. Node.js - Logging
• console
• log4js
• Winston
• GELF - Graylog Extended Log Format
• Windows Event Log
...
Saturday, October 6, 12

28. Node.js - Debugging
$ npm install node-inspector
$ node --debug-brk myapp.js
$ node --debug myapp.js
debugger listening on port 5858
$ node-inspector
visit http://0.0.0.0:8080/debug?port=5858 to start debugging
Debuggers
WebKit based: Chrome
Eclipse V8 Debugger Plugin, JetBrains WebStorm
Other Tools
v8-profiler, node-profiler
nodetime.com
Saturday, October 6, 12

29. Node.js - Inspector
Saturday, October 6, 12

30. Node.js - Debugging
Saturday, October 6, 12

31. Node.js - DB / ORM
Database Drivers
MS SQL, MongoDB, PostgreSQL, MySQL, Oracle, SQLite,
Redis, CouchDB, Hive, Riak, Cassandra
ORMs
sequelize, persist, LazyBoy, Model, jugglingdb, node-orm
Transactions, Connection Pooling
node-mysql-queues
Saturday, October 6, 12

32. Node.js - Web frameworks
• Derby
• Express
• Flatiron
• Meteor
• Mojito
• Tower
...
Browserify - Node to Browser conversion
Saturday, October 6, 12

33. Node.js - Testing frameworks
• assert - built in
• API Easy
• Cucumber
• httpmock, nock, mockery
• NodeUnit
• Soda
...
Saturday, October 6, 12

34. Node.js - Scaling out
Saturday, October 6, 12

35. Node.js - Scaling out
*Credit: blog.evantahler.com
Saturday, October 6, 12

36. Node.js - Wrapping up
• Reuse existing JavaScript skill and code
• Low resource usage
• Performant VM (Google’s V8)
• Active Community, Lots of resources
• Package Manager
• Enforces Async across
• Quick Prototyping
• Growing Industry support
Saturday, October 6, 12

37. Q &A
Saturday, October 6, 12