text: # Copyright (c) 2019 SAP SE or an SAP affiliate company. All rights reserved. This file is licensed
  # under the Apache Software License, v. 2 except as noted otherwise in the LICENSE file
  #
  # 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.
  
  from concourse.model.job import (
      JobVariant,
  )
  from concourse.model.base import (
    AttributeSpec,
    Trait,
    TraitTransformer,
  )
  
  
  ATTRIBUTES = (
      AttributeSpec.optional(
          name='suppress_parallel_execution',
          default=None,
          doc='whether parallel executions of the same job should be prevented',
          type=bool,
      ),
  )
  
  
  class SchedulingTrait(Trait):
      @classmethod
      def _attribute_specs(cls):
          return ATTRIBUTES
  
      # XXX: merge this with cron-trait
      def transformer(self):
          return SchedulingTraitTransformer()
  
      def suppress_parallel_execution(self):
          return self.raw.get('suppress_parallel_execution', None)
  
  
  class SchedulingTraitTransformer(TraitTransformer):
      name = 'scheduling'
  
      def process_pipeline_args(self, pipeline_args: JobVariant):
          # no-op
          pass
  