module Doorkeeper::Request

def authorization_strategy(response_type)
  grant_flow = authorization_flows.detect do |flow|
    flow.matches_response_type?(response_type)
  end
  if grant_flow
    grant_flow.response_type_strategy
  else
    # [NOTE]: this will be removed in a newer versions of Doorkeeper.
    # For retro-compatibility only
    build_fallback_strategy_class(response_type)
  end
end