Ruby on Rails is a web application framework that follows the model-view-controller (MVC) pattern. It uses RESTful routing and conventions to map HTTP verbs like GET and POST to controller actions. Models define the data and behavior of an application, controllers handle and respond to user input, and views display the UI for users. Rails emphasizes conventions over configuration for productivity and includes features like caching, asset pipelining, and internationalization.

1. Ruby on Rails
Technology

2. MVC

3. Model
Controller
View

4. MVC
●
Controller
Model
●
View

5. MVC

6. RESTful routing
REST
Representational state transfer

7. RESTful routing
HTTP Verb Path Action
GET /posts index
GET /posts/new new
POST /posts create
GET /posts/:id show
GET /posts/:id/edit edit
PUT /posts/:id update
DELETE /posts/:id destroy

8. RESTful routing
Configuration
resources :posts

9. Model
class Post < ActiveRecord::Base
validates :title, :presence => true
end

10. Controller
class PostController < ApplicationController
def index
@posts = Post.all
logger.info 'Post loaded'
end
end

11. View
<h1>Listing posts</h1>
<table>
<tr>
<th>Name</th>
<th>Title</th>
<th>Content</th>
</tr>
<% @posts.each do |post| %>
<tr>
<td><%= post.name %></td>
<td><%= post.title %></td>
<td><%= post.content %></td>
</tr>
<% end %>
</table>

12. Technology
●
Unobtrusive Javascript
●
Built in jquery and prototype
●
Coffeescript
●
HTML 5
●
Haml / Sass
●
Internationalization
●
Data migration
●
Dependency management

13. Performance
Improve performance
●
Caching
●
Asset pipeline
Test performance

14. Improve performance
Caching
- Page caching
- Action caching
- Fragment Caching
●
Reference
●
http://guides.rubyonrails.org/caching_with_rails.html

15. Configuration
config.action_controller.perform_caching = true

16. Page caching
class ProductsController < ActionController
caches_page :index
def index
@products = Products.all
end
def create
expire_page :action => :index
end
end

17. Page caching
Appropriate for Not for
●
Public pages ●
Pages that require
●
Pages that do not authentication
change often ●
Pages that changes
often

18. Action caching
class ProductsController < ActionController
before_filter :authenticate
caches_action :index
def index
@products = Product.all
end
def create
expire_action :action => :index
end
end

19. Fragment caching
In template
<% cache('all_available_products') do %>
All available products:
<% Product.all.each do |p| %>
<%= link_to p.name, product_url(p) %>
<% end %>
<% end %>
Expire cach
expire_fragment('all_available_products')

20. Caching
Use Sweepers to expire cache

21. Sweepers to expire caching
class ProductSweeper < ActionController::Caching::Sweeper
observe Product # This sweeper is going to keep an eye on the Product model
def after_create(product)
expire_cache_for(product)
end
def after_update(product)
expire_cache_for(product)
end
def after_destroy(product)
expire_cache_for(product)
end
private
def expire_cache_for(product)
expire_page(:controller => 'products', :action => 'index')
expire_fragment('all_available_products')
end
end

22. Sweepers to expire caching
class ProductsController < ActionController
before_filter :authenticate
caches_action :index
cache_sweeper :product_sweeper
def index
@products = Product.all
end
end

23. Configure caching
ActionController::Base.cache_store = :memory_store
or
ActionController::Base.cache_store = :file_store, "/path/to/cache/directory"
or
ActionController::Base.cache_store = :mem_cache_store, "cache-1.example.com"

24. Test performance
●
Benchmarking web site performance
●
class HomepageTest < ActionDispatch::PerformanceTest
# Replace this with your real tests.
def test_homepage
get '/'
end
end
http://guides.rubyonrails.org/performance_testing.html

25. Improve performance
Asset pipeline ???
●
Reference
●
http://guides.rubyonrails.org/asset_pipeline.html

26. Asset pipelining

27. Asset pipelining
Assets

28. Asset pipelining
Compile Compiled asset
Assets

29. Asset pipelining
Usage
app/assets/javascripts/application.js
app/assets/javascripts/home.js
app/assets/javascripts/menu.js
app/assets/javascripts/slider.js
Compiled asset
Assets

30. Asset pipelining
Usage
In application.js add the following,
//= require home
//= require moovinator
Compiled asset
//= require slider
Assets

31. Asset pipelining
Usage
Add application.js in you template as follows,
<%= javascript_include_tag "application" %>
Compiled asset
Assets

32. Deployment
●
Using capistrano magic
●
● cap deploy
●
Reference Compiled asset
●
https://github.com/capistrano/capistrano/wiki
Assets

33. Learn Rails
●
Guides
●
http://guides.rubyonrails.org
●
●
Video casts
●
http://railscasts.com
●
http://rubyonrails.org/screencasts asset
Compiled
Assets

34. A.K.M.
Ashrafuzzaman
Sr. Technology Analyst,
Orbund
www.ashrafuzzaman.com
jitu-blog.blogspot.com
www.orbund.com

35. Presented At
http://www.softexpo.com.bd/technical_details.php?id=9
To see 1st part of this presentation visit:
http://www.slideshare.net/fuadcse/ride-on-the-fast-track-of-web-with-ruby-on-rails-part-1