class Travis::Client::Entity

def relation(name)
  name   = name.to_s
  entity = Entity.subclass_for(name)
  if entity.many == name
    Array(send("#{entity.one}_ids")).map do |id|
      session.find_one(entity, id)
    end
  else
    id = send("#{name}_id")
    session.find_one(entity, id) unless id.nil?
  end
end