Module: Seatbelt::GhostTunnel

Extended by:
GhostTunnel
Included in:
GhostTunnel
Defined in:
lib/seatbelt/core/ghost_tunnel.rb

Overview

Public: Provides switches to enable accessing the implementation instance of an API class instances.

Any API class that implements Seatbelt::Ghost can have access to its implementation class instance. This behaviour has to be enabled before using because its a violation of the Public/Private API approach.

(And yes - in Ruby private methods are not really private methods.)

Accessing the implementation instance is only available after the API Class was instantiated.

Example:

class Hotel

include Seatbelt::Ghost

enable_tunneling! # access to the implementation instance is not
                  # possible.

end

class ImplementationHotel

include Seatbelt::Document
include Seatbelt::Gate

attribute :ignore_dirty_rooms, Boolean

end

hotel = new Hotel hotel.tunnel(:ignore_dirty_rooms=,false)

Passing blocks is also available if the accessed method supports blocks

class ImplementationHotel

include Seatbelt::Document
include Seatbelt::Gate

attribute :ignore_dirty_rooms, Boolean

def filter_rooms(sections)
  rooms = self.rooms.map{|room| sections.include?(room_type)}
  yield(rooms)
end

end

hotel.tunnel(:filter_rooms, [“shower, kitchen”]) do |rooms|

rooms.select do |room|
  # do something
end

end

Instance Method Summary collapse

Instance Method Details

#disable_tunneling! ⇒ Object

Public: Disables tunnel support for an instance of API class.

Removes the #tunnel method defined in #enable_tunneling! .



74
75
76
77
78
 
# File 'lib/seatbelt/core/ghost_tunnel.rb', line 74

def disable_tunneling!
  if self.instance_methods.include?(:tunnel)
    remove_method(:tunnel)
  end
end

#enable_tunneling! ⇒ Object

Public: Enables tunnel support for an instance of API class.

Defines the #tunnel method.



61
62
63
64
65
66
67
68
69
 
# File 'lib/seatbelt/core/ghost_tunnel.rb', line 61

def enable_tunneling!
  define_method :tunnel do |name, *args, &block|
    callees = self.eigenmethods.map{|n| n.instance_variable_get(:@callee)}
    unless callees.empty?
      callee = callees.first
      callee.send(name, *args, &block)
    end
  end
end