text: # Copyright 2020 The Couler Authors. All rights reserved.
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  # http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  import types
  
  from couler.core import states
  from couler.core.constants import WFStatus
  
  
  def set_exit_handler(status, exit_handler):
      """
      Configure the workflow handler
      Status would be: Succeeded, Failed, or Error.
      Each status invokes one exi_handler function.
      https://github.com/argoproj/argo/blob/master/examples/exit-handlers.yaml
      """
      if not isinstance(exit_handler, types.FunctionType):
          raise SyntaxError("require exit handler is a function")
  
      if not isinstance(status, WFStatus):  # noqa: F405
          raise SyntaxError(
              "require input status to be Succeeded, Failed or Error"
          )
  
      workflow_status = "{{workflow.status}} == %s" % status.value
  
      states._exit_handler_enable = True
      states._when_prefix = workflow_status
  
      if isinstance(exit_handler, types.FunctionType):
          branch = exit_handler()
          if branch is None:
              raise SyntaxError("require function return value")
      else:
          raise TypeError("condition to run would be a function")
  
      states._when_prefix = None
      states._exit_handler_enable = False
  