Slides from my Railsconf 2009 talk

1. Rails Metal,
Rack, and Sinatra
Adam Wiggins
Railsconf 2009

2. Show of hands, how
many of you...

3. metal

4. Show of hands, how
many of you...

6. “The gateway drug”

7. “The gateway drug”*
* it’s a myth, but makes good analogy

8. Rails Metal is a
gateway

9. Rails Metal is a
gateway to the
world of Rack

10. What can you do with
Metal?

11. Replace selected
URLs for a speed
boost

12. Example: auction site

14. Example: auction site

15. Example: auction site
on

18. Majority of traffic goes to:
GET /auctions/id.xml

19. app/controller/auctions_controller.rb

20. app/controller/auctions_controller.rb
class AuctionsController < ApplicationController
def show
@auction = Auction.find(params[:id])
respond_to do |format|
format.html
format.xml { render :xml => @auction }
end
end
end

21. app/metal/auctions_api.rb

22. app/metal/auctions_api.rb
class AuctionsApi
def self.call(env)
# implementation goes here
end
end

23. app/metal/auctions_api.rb
class AuctionsApi
def self.call(env)
url_pattern = %r{/auctions/(d+).xml}
if m = env['PATH_INFO'].match(url_pattern)
# render the auction api
else
# pass (do nothing)
end
end
end

24. app/metal/auctions_api.rb
class AuctionsApi
def self.call(env)
url_pattern = %r{/auctions/(d+).xml}
if m = env['PATH_INFO'].match(url_pattern)
auction = Auction.find(m[1])
[ 200, {quot;Content-Typequot; => quot;text/xmlquot;},
auction.to_xml ]
else
[ 404, {}, '' ]
end
end
end

25. [
200,
{quot;Content-Typequot;=>quot;text/plainquot;},
quot;Hello, Rack!quot;
]

26. [
200,
{quot;Content-Typequot;=>quot;text/plainquot;},
quot;Hello, Rack!quot;
]

28. http://www.slideshare.net/adamwiggins/
ruby-isnt-just-about-rails-presentation

29. An explosion of Ruby
projects in the past 2
years

30. Tests/Specs
Web Layer
Test::Unit
ActionController
RSpec
Merb
Shoulda
Sinatra
ORM Templating
ActiveRecord Erb
DataMapper Haml
Sequel Erubis
Web Server
HTTP Client
Mongrel
ActiveResource
Thin
RestClient
Ebb
HTTParty

31. Tests/Specs
Web Layer
Test::Unit
ActionController
ORM Templating
ActiveRecord Erb
Web Server
HTTP Client
Mongrel
ActiveResource

32. Tests/Specs
Web Layer
Test::Unit
ActionController
ORM Templating
ActiveRecord Erb
Web Server
HTTP Client
Mongrel
ActiveResource

33. Tests/Specs
Web Layer
Test::Unit
ActionController
RSpec
Merb
Shoulda
Sinatra
ORM Templating
ActiveRecord Erb
DataMapper Haml
Sequel Erubis
Web Server
HTTP Client
Mongrel
ActiveResource
Thin
RestClient
Ebb
HTTParty

34. Tests/Specs
Web Layer
Test::Unit
ActionController
RSpec
Merb
Shoulda
Sinatra
ORM Templating
ActiveRecord Erb
DataMapper Haml
Sequel Erubis
Web Server
HTTP Client
Mongrel
ActiveResource
Thin
RestClient
Ebb
HTTParty

35. Tests/Specs
Web Layer
Test::Unit
ActionController
RSpec
Merb
Shoulda
Sinatra
ORM Templating
ActiveRecord Erb
DataMapper Haml
Sequel Erubis
Web Server
HTTP Client
Mongrel
ActiveResource
Thin
RestClient
Ebb
HTTParty

38. The world of Rack is
now within reach from
Rails

39. Sinatra
The classy
microframework for Ruby
http://sinatrarb.com

40. require 'rubygems'
require 'sinatra'
get '/hello' do
quot;Hello, whirledquot;
end

41. $ ruby hello.rb
== Sinatra/0.9.1.1 has taken the stage
>> Thin web server (v1.0.0)
>> Maximum connections set to 1024
>> Listening on 0.0.0.0:4567

42. $ ruby hello.rb
== Sinatra/0.9.1.1 has taken the stage
>> Thin web server (v1.0.0)
>> Maximum connections set to 1024
>> Listening on 0.0.0.0:4567
$ curl http://localhost:4567/hello
Hello, whirled

43. A minimalist paradise

44. require 'rubygems'
require 'sinatra'
require 'lib/article'
post '/articles' do
article = Article.create! params
redirect quot;/articles/#{article.id}quot;
end
get '/articles/:id' do
@article = Article.find(params[:id])
erb :article
end

45. Sinatra in your Rails
app?

46. Replace selected
URLs for a speed
boost

47. Replace selected
URLs for a speed
boost

48. Replace selected
URLs with Sinatra

49. app/metal/articles.rb

50. app/metal/articles.rb
require 'sinatra/base'
class Articles < Sinatra::Base
post '/articles' do
article = Article.create! params
redirect quot;/articles/#{article.id}quot;
end
get '/articles/:id' do
@article = Article.find(params[:id])
erb :article
end
end

51. Back to the auction
example

52. Back to the auction
example

53. ActionController
class AuctionsController < ApplicationController
def show
@auction = Auction.find(params[:id])
respond_to do |format|
format.html
format.xml { render :xml => @auction }
end
end
end

54. Pure Rack
class AuctionsApi
def self.call(env)
url_pattern = /^/auctions/(d+).xml$/
if m = env['PATH_INFO'].match(url_pattern)
auction = Auction.find(m[1])
[ 200, {quot;Content-Typequot; => quot;text/xmlquot;},
auction.to_xml ]
else
[ 404, {}, '' ]
end
end
end

55. Sinatra
get '/auctions/:id.xml'
Auction.find(params[:id]).to_xml
end

56. Sinatra
get '/auctions/:id.xml'
Auction.find(params[:id]).to_xml
end
Now that’s what I call
minimalist.

57. The End.
http://railscasts.com/episodes/150-rails-metal
http://rack.rubyforge.org
http://sinatrarb.com
http://adam.blog.heroku.com
Adam Wiggins
Railsconf 2009