stream.py 1.3 KB

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  1. # Copyright 2015 gRPC authors.
  2. #
  3. # Licensed under the Apache License, Version 2.0 (the "License");
  4. # you may not use this file except in compliance with the License.
  5. # You may obtain a copy of the License at
  6. #
  7. # http://www.apache.org/licenses/LICENSE-2.0
  8. #
  9. # Unless required by applicable law or agreed to in writing, software
  10. # distributed under the License is distributed on an "AS IS" BASIS,
  11. # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12. # See the License for the specific language governing permissions and
  13. # limitations under the License.
  14. """Interfaces related to streams of values or objects."""
  15. import abc
  16. class Consumer(abc.ABC):
  17. """Interface for consumers of finite streams of values or objects."""
  18. @abc.abstractmethod
  19. def consume(self, value):
  20. """Accepts a value.
  21. Args:
  22. value: Any value accepted by this Consumer.
  23. """
  24. raise NotImplementedError()
  25. @abc.abstractmethod
  26. def terminate(self):
  27. """Indicates to this Consumer that no more values will be supplied."""
  28. raise NotImplementedError()
  29. @abc.abstractmethod
  30. def consume_and_terminate(self, value):
  31. """Supplies a value and signals that no more values will be supplied.
  32. Args:
  33. value: Any value accepted by this Consumer.
  34. """
  35. raise NotImplementedError()