Rack is a Ruby web server interface specification for building web applications. It defines an API for web servers to communicate with Ruby applications. Rack applications respond to the call method and return a three-element array containing the status, headers, and response. Rails uses Rack as its interface to communicate with web servers like WEBrick or Unicorn. Rack middleware can be added to Rails applications to add functionality like access logging or authentication. Common uses of Rack middleware include visitor counting, blocking access, and authentication with Devise.

1. Monday, February 24, 14
1

2. O QUE É?
Monday, February 24, 14
2

3. UMA ESPECIFICAÇÃO PARA
COMUNICAÇÃO ENTRE
APLICAÇÕES RUBY E
SERVIDORES WEB
Monday, February 24, 14
3

4. Request
Monday, February 24, 14
WebServer
Rack App
4

5. API RACK APP
Qualquer objeto que responde ao metodo call e receba como
parâmetro um objeto com os dados da requisição
Retorna um array com 3 elementos
[status, headers, response]
Monday, February 24, 14
5

6. API RACK APP
[status, headers, response]
to_i
Monday, February 24, 14
hash string
each
6

7. EXEMPLO
Monday, February 24, 14
7

8. proc {|env|
[200,
{"content-Type": "text/html"},
["Olá frevoonrails"]]
Monday, February 24, 14
8

9. RACK MIDDLEWARES
Monday, February 24, 14
9

10. Request
Middleware
Middleware
Rack App
Monday, February 24, 14
10

11. RAILS ON RACK
Monday, February 24, 14
11

12. RAKE MIDDLEWARE
Monday, February 24, 14
12

13. ADICIONANDO UM
RACK MIDDLEWARE AO
RAILS
Monday, February 24, 14
13

14. Crie seu arquivo “rack.rb” e adicione na pasta lib ou initializers
Monday, February 24, 14
14

15. Adicione seu rack application application.rb
Monday, February 24, 14
15

16. Verifique com “rake middleware”
Monday, February 24, 14
16

17. USOS NA VIDA REAL
Contador de acessos
Bloquear acesso
Devise(Warden)
Monday, February 24, 14
17

18. REFERÊNCIAS
http://guides.rubyonrails.org/rails_on_rack.html
http://rack.github.io/
https://www.youtube.com/watch?v=TslkdT3PfKc&
https://github.com/hassox/warden
Monday, February 24, 14
18

19. OBRIGADO!!
Monday, February 24, 14
19

20. OPS MAIS UMA COISA!!
Monday, February 24, 14
20

21. Monday, February 24, 14
21