The document provides an introduction to Ruby on Rails, a web application framework built using the Ruby programming language. It discusses Ruby's object-oriented nature and conventions. Rails uses the MVC pattern and ActiveRecord pattern. Rails allows developers to build web apps faster by automatically generating the scaffolding for database access, controllers and views. The document recommends additional resources for learning more about Ruby and Rails.

1. Ruby on Rails
An Introduction
Mark S. Maglana, CompE, MM

2. Let's get this out of the way...
» My name is Mark S. Maglana
» Bachelor's Degree in Computer Engineering from
the University of San Carlos, Cebu
» Master in Management from the University of the
Philippines in Mindanao
» Computer geek since grade 5 (BASIC, QBASIC)
» Suffered through C, assembly in college
» Web dude since 1997, started with ASP 1.0
» ASP.Net, PHP (w/ CakePHP)
» UML, VB, .Net, C#, Java, Lotus Notes/Domino

3. “I constantly remind myself that there are multiple
ways and numerous technologies [for] solving a
single problem, some better than others.”
“By being loyal to one technology stack, I am bound
to unconsciously make biased decisions, which will
ultimately hinder my ability to deliver business
value.”
- Stephen Chu
http://tinyurl.com/zz995

4. Ruby on Rails
A Programming
Language
A Web Framework
built w/ Ruby

5. Hold it right there, sparky...

6. This is an introduction, not a tutorial
We wont get in-depth with Ruby and Rails
(You're too intelligent to be spoon fed)
I assume you're familiar with OOP

7. Ruby
» Created by Yukihiro “Matz” Matsumoto in 1993
» A language designed for humans, not compilers
» A true Object-Oriented language
» Everything you manipulate in Ruby is an object
» They all ultimately inherit from a class named
Object (Surprise! Surprise!)
» Because everything is an object, there's none of
that primitive types vs. reference types silliness.

8. Hello World
# The famous Hello World
# program is trivial in
# Ruby. You don't need:
#
# * a "main" method
# * newline escapes
# * semicolons
#
# Here's the code:
puts "Hello World!"
Ruby won't force you to define a class if you don't
need to. In such a case, Ruby automatically
encloses your statement in an Object instance.

9. Other Examples
door.close if door.is_open?
5.times { puts “Odelay!” }
my_text = 'restaurant'
exit unless my_text.include? 'rant'
animals = ['cat', 'dog', 'fox']
animals.each {|animal| puts animal.capitalize}
small_number = 1212123
really_big_number = 1412432423429340234581340234
pretty_number = 12_000_000_000

10. And here's one more...
class Person
attr_accessor :name, :age, :sex
end
person = Person.new
person.name = 'Perting E. Soga'
person.age = 36
person.sex = 'M'
puts person.name # Perting E. Soga
puts person.age # 36
puts person.sex # M

11. Ruby Conventions
» Variables starting with $ are Global Variables
(ex. $x, $1, $chunky_bacon)
» Variables starting with @ are Instance Variables
(ex. @width, @x, @y)
» Variables starting with @@ are Class Variables
(ex. @@brokeback_coding, @@choo_choo)
» Variables without prefixes are Local Variables
(ex. chicken_noodles, white_flower)
» Constants are always capitalized
(ex. Time, Array, LuckyPenguin)

12. Rails
» Created by David Heinemeier Hansson in 2003
» A web application framework built using Ruby
» Uses the Model-View-Controller (MVC) design
pattern
» Also uses the ActiveRecord design pattern
» Some ex-Java programmers claim Rails helped
them develop applications 10x faster

13. Show me the money!
code

14. How Rails Works
Internet Web Server
controller
database
view
/posts/show/1
posts_controller.rb
model
post.rb
show.rhtml
blog_production
PostsController::show()
Post::find(1)
1.
2.
3.
4.
5.
6.
7.
8.
9.

15. Recommended Set-up
Internet Apache 2.2+
MongrelMongrel Mongrel
database
mod_proxy
mod_proxy_balancer
HTTP
HTTP HTTP HTTP

16. Additional Reading
» www.ruby-lang.org
» www.rubyonrails.org
» http://pine.fm/LearnToProgram/
» ruby-phil@googlegroups.com
» Google for “OnLAMP Rolling with Rails”
» #rubyonrails and #ruby-lang in IRC (freenode)
» wiki.rubyonrails.org
» api.rubyonrails.org
» Agile Web Development book
» Programming Ruby book

17. And we're done!