Adding new actions in a controller from a Helper - Ramaze/ramaze GitHub Wiki

Adding an action means that the method mixed in the controller will be reachable via URL routing. There is at least two ways to add new actions from a Helper.

The "Hard" Way

If you define methods using class_eval, they will "belong" to the controller (and not from the mixed-in helper) and thus will be available as actions.

In the following example, we define a add method in the controller from our Hardculator helper :

module Ramaze
  module Helper
    module Hardculator
      def self.included(c)
        c.class_eval {
          define_method(:add) { |*args|
            args.map(&:to_i).inject(:+)
          }
        }
      end
    end
  end
end

self.included is a hook that will be called when the Hardculator module is mixed in the controller's class. The c argument is the controller's Class. We can then ask c to class_eval the definition of a new method (:add) that just sums the arguments it receives.

Now, when /controller/add/1/2/3/4 is invoked, the action will return 10 (see the complete example in the bottom of the page).

The Easy Way (© manveru)

The other way is to use the EXPOSE Set in Ramaze::Helper : all the modules listed in this Set will be exposed as actions in the controller that mixes them in.

In the following example, we define a add method in the controller from our Easyculator helper :

module Ramaze
  module Helper
    module Easyculator
      # Expose helper methods as actions
      Ramaze::Helper::EXPOSE << self

      def add(*args)
        args.map(&:to_i).inject(:+)
      end
    end
  end
end

Pros & Cons

• The Easy Way :

• pros : it's straightforward

• cons : it makes all the modules method's available as acxtions (this might not be what you want)

• The "Hard" way :

• pros : you can choose specifically what new actions yu can to add

• cons : less readable

Complete self-contained example

require 'ramaze'

# Helpers
module Ramaze
  module Helper

    module Hardculator
      def self.included(c)
        c.class_eval {
          define_method(:add) { |*args|
            args.map(&:to_i).inject(:+)
          }
        }
      end
    end

    module Easyculator
      # Expose helper methods as actions
      Ramaze::Helper::EXPOSE << self

      def add(*args)
        args.map(&:to_i).inject(:+)
      end
    end

  end
end

# Controllers
class Easy < Ramaze::Controller
  layout nil
  helper :easyculator
end

class Hard < Ramaze::Controller
  layout nil
  helper :hardculator
end

Ramaze.start

Save as app.rb and run ruby app.rb.

Try to fetch the new actions with curl :

curl http://localhost:7000/easy/add/1/2/3 => 6

curl http://localhost:7000/hard/add/1/2/3 => 6

Have fun !