Ruby on Rails

1
Ruby on Rails

• Pei-Ying Wang
• peiatw_at_sfsu.edu

• Overview
• What is Ruby on Rails?
• Rails frameworks (components)
• Example simple web application
• Pros and Cons

2
What is Ruby on Rails?

• Ruby ? Ruby on Rails
• An open source, interpreted scripting language
• Created by Yukihiro Matsumoto in the mid-1990s
• Ruby on Rails, ROR or Rails
• An full-stack, open source web application
  framework written in Ruby
• Designed for writing database-oriented real-world
  Web application quickly and easily
• Created by David Heinemeier Hansson

3
What is Ruby on Rails?(2)

• Very short history
• Extracted from Basecamp(a project-management tool
  by 37Signals)
• First released July 2004
• Latest release April 2006(Version 1.1.2)
• Principles(DRY-Dont Repeat Yourself)
• Less software
• Convention over Configuration

4
Rails Frameworks(components)
5
Example a simple web application
After starting MySQL and Web server, Create a new
web application called cookbook2
gt Rails cookbook2
6
Example a simple web application(2)
To make a simple Hello World application
gt ruby script\generate controller MyTest
class MyTestController lt ApplicationController end

7
Example a simple web application(3)
To make a simple Hello World application(2)
class MyTestController lt ApplicationController de
f index render_text "Hello World" end end
http//localhost3000/My_Test/index http//localho
st3000//My_Test http//localhost3000/MyTest
8
Example a simple web application(4)

• Online Recipe
• First, create an database called cookbook2 and a
  table called recipes

9
Example a simple web application(5)
gt ruby script\generate model Recipe
10
Example a simple web application(6)
gt ruby script\generate controller Recipe
Magic happens by simply adding this line to
recipe_controller.rb ! ?Open browser and go
to http//localhost3000/recipe/new
11
Example a simple web application(7)
Now, you can start to populate the database
12
Example a simple web application(8)
13
Example a simple web application(9)

• Take over the handling of the list action from
  the scaffolding

Step1

• Add a list method in the file recipe_controller.r
  b

14
Example a simple web application(10)
lthtmlgt ltheadgt lttitlegtAll Recipeslt/titlegt lt/headgt lt
bodygt lth1gtOnline Cookbook - All
Recipeslt/h1gt lttable border"1"gt lttrgt lttd
width"80"gtltp align"center"gtltigtltbgtRecipelt/bgtlt/igt
lt/tdgt lttd width"20"gtltp align"center"gtltigtltbgtDat
elt/bgtlt/igtlt/tdgt lt/trgt lt _at_recipes.each do
recipe gt lttrgt lttdgtlt link_to recipe.title,
action gt "show", id gt recipe.id gtlt/tdgt
lttdgtlt recipe.date gtlt/tdgt lt/trgt lt end
gt lt/tablegt ltpgtlt link_to "Create new recipe",
action gt "new" gtlt/pgt lt/bodygt lt/htmlgt
Step2

• Add a new file called list.rhtml under
  app/views/receipe
• .rhtml an html file with Ruby code embedded
  within
• lt gt and
• lt gt tags

15
Example a simple web application(11)
Step3

• Ask the recipe class for a collection of all
  recipes from the DB and assign the collection to
  the instance variable _at_recipes

16
Example a simple web application(12)
Done!
http//localhost3000/recipe/list
17
Pros and Cons

• pros
• Less code
• High productivity reduced development time
• cons
• too young
• Upgrades in foundational code may result in
  instability in Rails
• Relies on a foundation of numerous other
  applications

18
Reference

• Russel Kay QUICK STUDY Ruby on Rails.
  Computerworld, 11/28/2005, Vol. 39 Issue 48,
  pg26-26
• David Geer Will Software Developers Rid Ruby on
  Rails to Success? Computer, Feb2006, Vol. 39
  Issue 2, pg18-20
• Stacy Cowley Riding the ruby rails in a new
  direction  CRN. Jericho Mar 13,
  2006., Issue 1187  pg. 43
• Grant Buckler Application developers climb
  aboard Ruby on Rails  Computing
  Canada. Willowdale Aug 19, 2005.Vol.31, Issue 11
    pg. 6
• Daniel Bogan Get on track with ruby on rails
  http//www.sitepoint.com/article/ruby-on-rails
• Curt HibbsWhat Is Ruby on Rails?
  http//www.onlamp.com/lpt/a/6251
•  Bill Walton Rolling with Ruby on InstantRails
  http//instantrails.rubyforge.org/tutorial/index.h
  tml
• Curt Hibbs Rolling with Ruby on Rails, Part 2
  http//www.onlamp.com/lpt/a/5641
• Curt Hibbs Ajax on Rails http//www.onlamp.com/lp
  t/a/5944
• http//en.wikipedia.org/wiki/Ruby_On_Rails
• http//www.rubyonrails.com/