http://stackoverflow.com/questions/20189404/rails-different-methods-for-different-users/

gistfile1.rb

class Api::Foobar
  include HTTParty
  base_uri 'http://demo.foobar.es/vweb/xml'

  GLOBAL_OPTIONS = {edad: 'anciano', farmacovigilancia: false, deportista: false, administrativas: false}

  def initialize(user)
    @user = user
  end

  def perform
    if @user.country=='France'
      contraindications
    else
      medications_by_name(@user.country_name)
    end
  end

  private

  def contraindications
    self.class.get("/ws_patient/alertas", query: GLOBAL_OPTIONS.merge(user_options) )
  end

  def self.medications_by_name(name)
    response = get("/ws_drug/SearchByName", query: {value: name} )
    response['object']['drug_set']['drug']
  end
end