DRY_your_sunspot_code.md

It worked !

class Ambassador
  include Searchable
end

class Speaker
  include Searchable
end

module Searchable
  extend ActiveSupport::Concern
  included do
    text :gender # == male || female
  end
  
  module ClassMethods
    def search_solr(params = {})
      solr_search do
        with(:gender, params[:gender])
      end
    end
  end
end

GOOD !

but . . . what if . . . Speaker need to be search by theme too ?

##0. Refacto the search with Sunspot.new_search

module Searchable
  module ClassMethods
    def search_solr(params = {})
      n_search = Sunspot.new_search(self) # self == Ambassador || Speaker
      search_by_gender(n_search, params)
      search = n_search.execute
    end
    
    private
    
    def search_by_gender(n_search, params)
      n_search.build do
        with(:gender, params[:gender])
      end
    end
  end
end

##1. Searchable

class Speaker
  include Searchable
  
  searchable do
    text(:theme)
  end
  # it does not overwrite the module list, it add this list to the module list ! 
end

##2 Add some specific search ####2.1 Complete the specific model

class Speaker
  # [...]
  class << self
    def search_solr(params = {})
      super { |n_search| search_by_theme(n_search, params) }
    end
  end
end

####2.2 complete the module

module Searchable
  module ClassMethods
    def search_solr(params = {})
      n_search = Sunspot.new_search(self)
      search_by_gender(n_search, params)
      yield(n_search) if block_given?
      search = n_search.execute
    end
    
    private
    
    # [...]
    
    def search_by_theme(n_search, params)
      n_search.build do
        with(:theme, params[:theme])
      end
    end
  end
end

TADAM !!

Resume:

class Ambassador
  include Searchable
end

class Speaker
  include Searchable
  
  searchable do
    text(:theme)
  end
  
  class << self
    def search_solr(params = {})
      super { |n_search| search_by_theme(n_search, params) }
    end
  end
end

module Searchable
  module ClassMethods
    def search_solr(params = {})
      n_search = Sunspot.new_search(self)
      search_by_gender(n_search, params)
      yield(n_search) if block_given?
      search = n_search.execute
    end
    
    private
    
    def search_by_gender(n_search, params)
      n_search.build do
        with(:gender, params[:gender])
      end
    end
    
    def search_by_theme(n_search, params)
      n_search.build do
        with(:theme, params[:theme])
      end
    end
  end
end