Question

I’m wondering what is the best way to initialize a class in ruby depending on modules included. Let me give you an example:

class BaseSearch
    def initialize query, options
        @page = options[:page]
        #...
    end
end


class EventSearch < BaseSearch
    include Search::Geolocalisable

    def initialize query, options
    end
end

class GroupSearch < BaseSearch
    include Search::Geolocalisable

    def initialize query, options
    end
end

module Search::Geolocalisable
    extend ActiveSupport::Concern

    included do
        attr_accessor :where, :user_location #...
    end
end

What I don’t want, is having to initialize the :where and :user_location variables on each class that include the geolocalisable module.

Currently, I just define methods like def geolocalisable?; true; end in my modules, and then, I initialize these attributes (added by the module) in the base class:

class BaseSearch
    def initialize query, options
        @page = options[:page]
        #...
        if geolocalisable?
            @where = query[:where]
        end
    end
end

class EventSearch < BaseSearch
    #...
    def initialize query, options
       #...
       super query, options
    end
end

Is there better solutions? I hope so!

Answer 1

Why not override initialize in the module? You could do

class BaseSearch
  def initialize query
    puts "base initialize"
  end
end

module Geo
  def initialize query
    super
    puts "module initialize"
  end
end

class Subclass < BaseSearch
  include Geo
  def initialize query
    super
    puts "subclass initialize"
  end
end

Subclass.new('foo') #=>
  base initialize
  module initialize
  subclass initialize

Obviously this does require everything that includes your modules to have an initialize with a similar signature or weird stuff might happen