| # Copyright 2015, Google Inc. |
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| |
| """State and behavior for handling emitted values.""" |
| |
| from grpc.framework.base import interfaces |
| from grpc.framework.base import _interfaces |
| |
| |
| class _EmissionManager(_interfaces.EmissionManager): |
| """An implementation of _interfaces.EmissionManager.""" |
| |
| def __init__( |
| self, lock, failure_outcome, termination_manager, transmission_manager): |
| """Constructor. |
| |
| Args: |
| lock: The operation-wide lock. |
| failure_outcome: Whichever one of interfaces.Outcome.SERVICED_FAILURE or |
| interfaces.Outcome.SERVICER_FAILURE describes this object's methods |
| being called inappropriately by customer code. |
| termination_manager: The _interfaces.TerminationManager for the operation. |
| transmission_manager: The _interfaces.TransmissionManager for the |
| operation. |
| """ |
| self._lock = lock |
| self._failure_outcome = failure_outcome |
| self._termination_manager = termination_manager |
| self._transmission_manager = transmission_manager |
| self._ingestion_manager = None |
| self._expiration_manager = None |
| |
| self._emission_complete = False |
| |
| def set_ingestion_manager_and_expiration_manager( |
| self, ingestion_manager, expiration_manager): |
| self._ingestion_manager = ingestion_manager |
| self._expiration_manager = expiration_manager |
| |
| def _abort(self): |
| self._termination_manager.abort(self._failure_outcome) |
| self._transmission_manager.abort(self._failure_outcome) |
| self._ingestion_manager.abort() |
| self._expiration_manager.abort() |
| |
| def consume(self, value): |
| with self._lock: |
| if self._emission_complete: |
| self._abort() |
| else: |
| self._transmission_manager.inmit(value, False) |
| |
| def terminate(self): |
| with self._lock: |
| if not self._emission_complete: |
| self._termination_manager.emission_complete() |
| self._transmission_manager.inmit(None, True) |
| self._emission_complete = True |
| |
| def consume_and_terminate(self, value): |
| with self._lock: |
| if self._emission_complete: |
| self._abort() |
| else: |
| self._termination_manager.emission_complete() |
| self._transmission_manager.inmit(value, True) |
| self._emission_complete = True |
| |
| |
| def front_emission_manager(lock, termination_manager, transmission_manager): |
| """Creates an _interfaces.EmissionManager appropriate for front-side use. |
| |
| Args: |
| lock: The operation-wide lock. |
| termination_manager: The _interfaces.TerminationManager for the operation. |
| transmission_manager: The _interfaces.TransmissionManager for the operation. |
| |
| Returns: |
| An _interfaces.EmissionManager appropriate for front-side use. |
| """ |
| return _EmissionManager( |
| lock, interfaces.Outcome.SERVICED_FAILURE, termination_manager, |
| transmission_manager) |
| |
| |
| def back_emission_manager(lock, termination_manager, transmission_manager): |
| """Creates an _interfaces.EmissionManager appropriate for back-side use. |
| |
| Args: |
| lock: The operation-wide lock. |
| termination_manager: The _interfaces.TerminationManager for the operation. |
| transmission_manager: The _interfaces.TransmissionManager for the operation. |
| |
| Returns: |
| An _interfaces.EmissionManager appropriate for back-side use. |
| """ |
| return _EmissionManager( |
| lock, interfaces.Outcome.SERVICER_FAILURE, termination_manager, |
| transmission_manager) |