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![class Hello status
def call(env) headers
[
200,
{ "Content-Type" => "text/plain" },
[ "Hello!", "Having fun yet?" ]
]
end
end body](https://image.slidesharecdn.com/rack-101021192406-phpapp02/75/Rack-7-2048.jpg)
![init with app
class Reverse
def initialize(app) first, Call the app
@app = app
end
def call(env)
status, headers, body = @app.call(env)
[status, headers, body.map { |b| b.reverse }]
end
end
then, do your stuff](https://image.slidesharecdn.com/rack-101021192406-phpapp02/75/Rack-10-2048.jpg)
![use Rack::ContentLength
use RackExamples::Paragraphizer
use RackExamples::Upcase
use
use
RackExamples::Downcase
RackExamples::Reverse
Is output upper or
app = lambda { |env| [
lower case?
200,
{ 'Content-Type' => 'text/html' },
["Dammit, I'm mad!",
"Was it a rat I saw?",
"Madam, I'm Adam"]
] }
run app
11](https://image.slidesharecdn.com/rack-101021192406-phpapp02/75/Rack-11-2048.jpg)
![use Rack::ContentLength
use RackExamples::Paragraphizer
use RackExamples::Downcase
use RackExamples::Upcase
use RackExamples::Reverse How about now?
app = lambda { |env| [
200,
{ 'Content-Type' => 'text/html' },
["Dammit, I'm mad!",
"Was it a rat I saw?",
"Madam, I'm Adam"]
] }
run app
12](https://image.slidesharecdn.com/rack-101021192406-phpapp02/75/Rack-12-2048.jpg)
Uploaded byScott Leberknight
Rack
The document discusses the Rack web server interface in Ruby. It explains that Rack defines the interface between web servers and web applications through requests and responses. A Rack application is any Ruby object that responds to call, accepting an environment hash and returning a status, headers, and body tuple. The document provides a simple Hello World Rack app as an example. It also discusses how middleware can modify requests and responses by forming a chain where each middleware calls the next. The order of middleware is important as it determines how requests and responses are modified. Common Rack middleware that are included for convenience are also listed.
More Related Content
Rack
- 1.
- 3. HTTP make request, getresponse
- 4. Request a hash containingthe environment (headers, params, input stream)
- 5.
- 6.
- 7. class Hello status def call(env) headers [ 200, { "Content-Type" => "text/plain" }, [ "Hello!", "Having fun yet?" ] ] end end body
- 8.
- 9. middlewares call() eachother... and act like chain of response filters... ...so the order you use them matters!
- 10. init with app classReverse def initialize(app) first, Call the app @app = app end def call(env) status, headers, body = @app.call(env) [status, headers, body.map { |b| b.reverse }] end end then, do your stuff
- 11. use Rack::ContentLength use RackExamples::Paragraphizer use RackExamples::Upcase use use RackExamples::Downcase RackExamples::Reverse Is output upper or app = lambda { |env| [ lower case? 200, { 'Content-Type' => 'text/html' }, ["Dammit, I'm mad!", "Was it a rat I saw?", "Madam, I'm Adam"] ] } run app 11
- 12. use Rack::ContentLength use RackExamples::Paragraphizer use RackExamples::Downcase use RackExamples::Upcase use RackExamples::Reverse How about now? app = lambda { |env| [ 200, { 'Content-Type' => 'text/html' }, ["Dammit, I'm mad!", "Was it a rat I saw?", "Madam, I'm Adam"] ] } run app 12
- 13. "Off t heShelf"
- 14.
- 15. Baked into Ra ils
- 16. $ rake middleware (in/Users/sleberkn/Projects/my-niclabs) use Rack::Lock use ActionController::Failsafe use ActionController::Session::CookieStore, #<Proc:0x00000001017acf18@(eval):8> use ActionController::ParamsParser use Rack::MethodOverride use Rack::Head use ActionController::StringCoercion use Rack::Deflater use Sass::Plugin::Rack use ActiveRecord::ConnectionAdapters::ConnectionManagement use ActiveRecord::QueryCache run ActionController::Dispatcher.new
- 17.
- 20.
- 21.
- 22.
- 23. scott.leberknight@nearinfinity.com www.nearinfinity.com/blogs/ twitter: sleberknight