Project: rack-respond_to - The Ruby Toolbox

Summary

Rack convenience middleware that allows triggering different actions based on requested media type. Standalone version of the equivalent Rails functionality.

Features

Based on familiar API (Rails)
Cascades down priority list of accepted media types
Handles wildcard media types
Simple to use
Simple code (~50 LOCs)
Flexible (standalone use)
Decently documented (examples/ dir, source docs/rdocs)
Compatible with other media type handling middleware (uses Rack::AcceptMediaTypes)

Install

gem install rack-respond_to

Example

require 'rack'
require 'rack/respond_to'

class App
  include Rack::RespondTo #mixes in #respond_to

  def call(env)
    # Pass in the env, and RespondTo will retrieve the requested media types
    Rack::RespondTo.env = env

    # Alternatively, to use standalone you can also assign the media types
    # directly (this will take precedence over the env)
    #Rack::RespondTo.media_types = ['text/html']

    body = respond_to do |format|
      format.html { '<em>html</em>' }
      format.xml  { '<body>xml</body>' }
    end

    [200, {'Content-Type' => Rack::RespondTo.selected_media_type}, [body]]
  end
end

run App.new

See examples/simple_app.ru for an executable example.

Tips

Use together with Rack::AbstractFormat to respond to routes based on url extensions. For example, if you want example.com/foo.xml to trigger the format.xml block (Rack::AbstractFormat moves the extension's media type into HTTP_ACCEPT and makes it the highest ranked).

gem install rack-abstract-format

See examples/recommended_use.ru for a complete example.

Acknowledgement

thanks to daicoden for format.any idea and initial patch

rack-respond_to

Development