1085 lines
39 KiB
Python
1085 lines
39 KiB
Python
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# Copyright 2015 gRPC authors.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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"""Interfaces defining the Face layer of RPC Framework."""
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import abc
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import collections
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import enum
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# cardinality, style, abandonment, future, and stream are
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# referenced from specification in this module.
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from grpc.framework.common import cardinality # pylint: disable=unused-import
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from grpc.framework.common import style # pylint: disable=unused-import
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from grpc.framework.foundation import future # pylint: disable=unused-import
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from grpc.framework.foundation import stream # pylint: disable=unused-import
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# pylint: disable=too-many-arguments
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class NoSuchMethodError(Exception):
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"""Raised by customer code to indicate an unrecognized method.
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Attributes:
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group: The group of the unrecognized method.
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name: The name of the unrecognized method.
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"""
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def __init__(self, group, method):
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"""Constructor.
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Args:
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group: The group identifier of the unrecognized RPC name.
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method: The method identifier of the unrecognized RPC name.
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"""
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super(NoSuchMethodError, self).__init__()
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self.group = group
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self.method = method
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def __repr__(self):
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return "face.NoSuchMethodError(%s, %s)" % (
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self.group,
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self.method,
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)
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class Abortion(
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collections.namedtuple(
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"Abortion",
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(
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"kind",
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"initial_metadata",
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"terminal_metadata",
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"code",
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"details",
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),
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)
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):
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"""A value describing RPC abortion.
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Attributes:
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kind: A Kind value identifying how the RPC failed.
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initial_metadata: The initial metadata from the other side of the RPC or
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None if no initial metadata value was received.
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terminal_metadata: The terminal metadata from the other side of the RPC or
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None if no terminal metadata value was received.
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code: The code value from the other side of the RPC or None if no code value
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was received.
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details: The details value from the other side of the RPC or None if no
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details value was received.
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"""
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@enum.unique
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class Kind(enum.Enum):
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"""Types of RPC abortion."""
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CANCELLED = "cancelled"
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EXPIRED = "expired"
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LOCAL_SHUTDOWN = "local shutdown"
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REMOTE_SHUTDOWN = "remote shutdown"
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NETWORK_FAILURE = "network failure"
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LOCAL_FAILURE = "local failure"
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REMOTE_FAILURE = "remote failure"
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class AbortionError(Exception, metaclass=abc.ABCMeta):
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"""Common super type for exceptions indicating RPC abortion.
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initial_metadata: The initial metadata from the other side of the RPC or
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None if no initial metadata value was received.
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terminal_metadata: The terminal metadata from the other side of the RPC or
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None if no terminal metadata value was received.
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code: The code value from the other side of the RPC or None if no code value
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was received.
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details: The details value from the other side of the RPC or None if no
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details value was received.
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"""
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def __init__(self, initial_metadata, terminal_metadata, code, details):
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super(AbortionError, self).__init__()
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self.initial_metadata = initial_metadata
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self.terminal_metadata = terminal_metadata
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self.code = code
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self.details = details
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def __str__(self):
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return '%s(code=%s, details="%s")' % (
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self.__class__.__name__,
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self.code,
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self.details,
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)
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class CancellationError(AbortionError):
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"""Indicates that an RPC has been cancelled."""
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class ExpirationError(AbortionError):
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"""Indicates that an RPC has expired ("timed out")."""
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class LocalShutdownError(AbortionError):
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"""Indicates that an RPC has terminated due to local shutdown of RPCs."""
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class RemoteShutdownError(AbortionError):
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"""Indicates that an RPC has terminated due to remote shutdown of RPCs."""
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class NetworkError(AbortionError):
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"""Indicates that some error occurred on the network."""
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class LocalError(AbortionError):
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"""Indicates that an RPC has terminated due to a local defect."""
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class RemoteError(AbortionError):
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"""Indicates that an RPC has terminated due to a remote defect."""
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class RpcContext(abc.ABC):
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"""Provides RPC-related information and action."""
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@abc.abstractmethod
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def is_active(self):
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"""Describes whether the RPC is active or has terminated."""
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raise NotImplementedError()
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@abc.abstractmethod
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def time_remaining(self):
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"""Describes the length of allowed time remaining for the RPC.
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Returns:
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A nonnegative float indicating the length of allowed time in seconds
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remaining for the RPC to complete before it is considered to have timed
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out.
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"""
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raise NotImplementedError()
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@abc.abstractmethod
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def add_abortion_callback(self, abortion_callback):
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"""Registers a callback to be called if the RPC is aborted.
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Args:
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abortion_callback: A callable to be called and passed an Abortion value
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in the event of RPC abortion.
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"""
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raise NotImplementedError()
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@abc.abstractmethod
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def cancel(self):
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"""Cancels the RPC.
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Idempotent and has no effect if the RPC has already terminated.
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"""
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raise NotImplementedError()
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@abc.abstractmethod
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def protocol_context(self):
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"""Accesses a custom object specified by an implementation provider.
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Returns:
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A value specified by the provider of a Face interface implementation
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affording custom state and behavior.
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"""
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raise NotImplementedError()
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class Call(RpcContext, metaclass=abc.ABCMeta):
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"""Invocation-side utility object for an RPC."""
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@abc.abstractmethod
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def initial_metadata(self):
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"""Accesses the initial metadata from the service-side of the RPC.
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This method blocks until the value is available or is known not to have been
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emitted from the service-side of the RPC.
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Returns:
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The initial metadata object emitted by the service-side of the RPC, or
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None if there was no such value.
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"""
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raise NotImplementedError()
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@abc.abstractmethod
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def terminal_metadata(self):
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"""Accesses the terminal metadata from the service-side of the RPC.
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This method blocks until the value is available or is known not to have been
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emitted from the service-side of the RPC.
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Returns:
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The terminal metadata object emitted by the service-side of the RPC, or
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None if there was no such value.
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"""
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raise NotImplementedError()
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@abc.abstractmethod
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def code(self):
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"""Accesses the code emitted by the service-side of the RPC.
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This method blocks until the value is available or is known not to have been
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emitted from the service-side of the RPC.
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Returns:
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The code object emitted by the service-side of the RPC, or None if there
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was no such value.
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"""
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raise NotImplementedError()
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@abc.abstractmethod
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def details(self):
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"""Accesses the details value emitted by the service-side of the RPC.
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This method blocks until the value is available or is known not to have been
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emitted from the service-side of the RPC.
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Returns:
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The details value emitted by the service-side of the RPC, or None if there
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was no such value.
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"""
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raise NotImplementedError()
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class ServicerContext(RpcContext, metaclass=abc.ABCMeta):
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"""A context object passed to method implementations."""
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@abc.abstractmethod
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def invocation_metadata(self):
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"""Accesses the metadata from the invocation-side of the RPC.
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This method blocks until the value is available or is known not to have been
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emitted from the invocation-side of the RPC.
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Returns:
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The metadata object emitted by the invocation-side of the RPC, or None if
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there was no such value.
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"""
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raise NotImplementedError()
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@abc.abstractmethod
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def initial_metadata(self, initial_metadata):
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"""Accepts the service-side initial metadata value of the RPC.
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This method need not be called by method implementations if they have no
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service-side initial metadata to transmit.
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Args:
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initial_metadata: The service-side initial metadata value of the RPC to
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be transmitted to the invocation side of the RPC.
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"""
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raise NotImplementedError()
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@abc.abstractmethod
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def terminal_metadata(self, terminal_metadata):
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"""Accepts the service-side terminal metadata value of the RPC.
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This method need not be called by method implementations if they have no
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service-side terminal metadata to transmit.
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Args:
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terminal_metadata: The service-side terminal metadata value of the RPC to
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be transmitted to the invocation side of the RPC.
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"""
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raise NotImplementedError()
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@abc.abstractmethod
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def code(self, code):
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"""Accepts the service-side code of the RPC.
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This method need not be called by method implementations if they have no
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code to transmit.
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Args:
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code: The code of the RPC to be transmitted to the invocation side of the
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RPC.
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"""
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raise NotImplementedError()
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@abc.abstractmethod
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def details(self, details):
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"""Accepts the service-side details of the RPC.
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This method need not be called by method implementations if they have no
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service-side details to transmit.
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Args:
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details: The service-side details value of the RPC to be transmitted to
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the invocation side of the RPC.
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"""
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raise NotImplementedError()
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class ResponseReceiver(abc.ABC):
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"""Invocation-side object used to accept the output of an RPC."""
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@abc.abstractmethod
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def initial_metadata(self, initial_metadata):
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"""Receives the initial metadata from the service-side of the RPC.
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Args:
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initial_metadata: The initial metadata object emitted from the
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service-side of the RPC.
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"""
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raise NotImplementedError()
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@abc.abstractmethod
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def response(self, response):
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"""Receives a response from the service-side of the RPC.
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Args:
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response: A response object emitted from the service-side of the RPC.
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"""
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raise NotImplementedError()
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@abc.abstractmethod
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def complete(self, terminal_metadata, code, details):
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"""Receives the completion values emitted from the service-side of the RPC.
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Args:
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terminal_metadata: The terminal metadata object emitted from the
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service-side of the RPC.
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code: The code object emitted from the service-side of the RPC.
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details: The details object emitted from the service-side of the RPC.
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"""
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raise NotImplementedError()
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class UnaryUnaryMultiCallable(abc.ABC):
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"""Affords invoking a unary-unary RPC in any call style."""
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@abc.abstractmethod
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def __call__(
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self,
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request,
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timeout,
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metadata=None,
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with_call=False,
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protocol_options=None,
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):
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"""Synchronously invokes the underlying RPC.
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Args:
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request: The request value for the RPC.
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timeout: A duration of time in seconds to allow for the RPC.
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metadata: A metadata value to be passed to the service-side of
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the RPC.
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with_call: Whether or not to include return a Call for the RPC in addition
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to the response.
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protocol_options: A value specified by the provider of a Face interface
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implementation affording custom state and behavior.
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Returns:
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The response value for the RPC, and a Call for the RPC if with_call was
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set to True at invocation.
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Raises:
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AbortionError: Indicating that the RPC was aborted.
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"""
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raise NotImplementedError()
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@abc.abstractmethod
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def future(self, request, timeout, metadata=None, protocol_options=None):
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"""Asynchronously invokes the underlying RPC.
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Args:
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request: The request value for the RPC.
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timeout: A duration of time in seconds to allow for the RPC.
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metadata: A metadata value to be passed to the service-side of
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the RPC.
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||
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protocol_options: A value specified by the provider of a Face interface
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||
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implementation affording custom state and behavior.
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||
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Returns:
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||
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An object that is both a Call for the RPC and a future.Future. In the
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||
|
|
event of RPC completion, the return Future's result value will be the
|
||
|
|
response value of the RPC. In the event of RPC abortion, the returned
|
||
|
|
Future's exception value will be an AbortionError.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def event(
|
||
|
|
self,
|
||
|
|
request,
|
||
|
|
receiver,
|
||
|
|
abortion_callback,
|
||
|
|
timeout,
|
||
|
|
metadata=None,
|
||
|
|
protocol_options=None,
|
||
|
|
):
|
||
|
|
"""Asynchronously invokes the underlying RPC.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
request: The request value for the RPC.
|
||
|
|
receiver: A ResponseReceiver to be passed the response data of the RPC.
|
||
|
|
abortion_callback: A callback to be called and passed an Abortion value
|
||
|
|
in the event of RPC abortion.
|
||
|
|
timeout: A duration of time in seconds to allow for the RPC.
|
||
|
|
metadata: A metadata value to be passed to the service-side of
|
||
|
|
the RPC.
|
||
|
|
protocol_options: A value specified by the provider of a Face interface
|
||
|
|
implementation affording custom state and behavior.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
A Call for the RPC.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
|
||
|
|
class UnaryStreamMultiCallable(abc.ABC):
|
||
|
|
"""Affords invoking a unary-stream RPC in any call style."""
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def __call__(self, request, timeout, metadata=None, protocol_options=None):
|
||
|
|
"""Invokes the underlying RPC.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
request: The request value for the RPC.
|
||
|
|
timeout: A duration of time in seconds to allow for the RPC.
|
||
|
|
metadata: A metadata value to be passed to the service-side of
|
||
|
|
the RPC.
|
||
|
|
protocol_options: A value specified by the provider of a Face interface
|
||
|
|
implementation affording custom state and behavior.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
An object that is both a Call for the RPC and an iterator of response
|
||
|
|
values. Drawing response values from the returned iterator may raise
|
||
|
|
AbortionError indicating abortion of the RPC.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def event(
|
||
|
|
self,
|
||
|
|
request,
|
||
|
|
receiver,
|
||
|
|
abortion_callback,
|
||
|
|
timeout,
|
||
|
|
metadata=None,
|
||
|
|
protocol_options=None,
|
||
|
|
):
|
||
|
|
"""Asynchronously invokes the underlying RPC.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
request: The request value for the RPC.
|
||
|
|
receiver: A ResponseReceiver to be passed the response data of the RPC.
|
||
|
|
abortion_callback: A callback to be called and passed an Abortion value
|
||
|
|
in the event of RPC abortion.
|
||
|
|
timeout: A duration of time in seconds to allow for the RPC.
|
||
|
|
metadata: A metadata value to be passed to the service-side of
|
||
|
|
the RPC.
|
||
|
|
protocol_options: A value specified by the provider of a Face interface
|
||
|
|
implementation affording custom state and behavior.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
A Call object for the RPC.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
|
||
|
|
class StreamUnaryMultiCallable(abc.ABC):
|
||
|
|
"""Affords invoking a stream-unary RPC in any call style."""
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def __call__(
|
||
|
|
self,
|
||
|
|
request_iterator,
|
||
|
|
timeout,
|
||
|
|
metadata=None,
|
||
|
|
with_call=False,
|
||
|
|
protocol_options=None,
|
||
|
|
):
|
||
|
|
"""Synchronously invokes the underlying RPC.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
request_iterator: An iterator that yields request values for the RPC.
|
||
|
|
timeout: A duration of time in seconds to allow for the RPC.
|
||
|
|
metadata: A metadata value to be passed to the service-side of
|
||
|
|
the RPC.
|
||
|
|
with_call: Whether or not to include return a Call for the RPC in addition
|
||
|
|
to the response.
|
||
|
|
protocol_options: A value specified by the provider of a Face interface
|
||
|
|
implementation affording custom state and behavior.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
The response value for the RPC, and a Call for the RPC if with_call was
|
||
|
|
set to True at invocation.
|
||
|
|
|
||
|
|
Raises:
|
||
|
|
AbortionError: Indicating that the RPC was aborted.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def future(
|
||
|
|
self, request_iterator, timeout, metadata=None, protocol_options=None
|
||
|
|
):
|
||
|
|
"""Asynchronously invokes the underlying RPC.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
request_iterator: An iterator that yields request values for the RPC.
|
||
|
|
timeout: A duration of time in seconds to allow for the RPC.
|
||
|
|
metadata: A metadata value to be passed to the service-side of
|
||
|
|
the RPC.
|
||
|
|
protocol_options: A value specified by the provider of a Face interface
|
||
|
|
implementation affording custom state and behavior.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
An object that is both a Call for the RPC and a future.Future. In the
|
||
|
|
event of RPC completion, the return Future's result value will be the
|
||
|
|
response value of the RPC. In the event of RPC abortion, the returned
|
||
|
|
Future's exception value will be an AbortionError.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def event(
|
||
|
|
self,
|
||
|
|
receiver,
|
||
|
|
abortion_callback,
|
||
|
|
timeout,
|
||
|
|
metadata=None,
|
||
|
|
protocol_options=None,
|
||
|
|
):
|
||
|
|
"""Asynchronously invokes the underlying RPC.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
receiver: A ResponseReceiver to be passed the response data of the RPC.
|
||
|
|
abortion_callback: A callback to be called and passed an Abortion value
|
||
|
|
in the event of RPC abortion.
|
||
|
|
timeout: A duration of time in seconds to allow for the RPC.
|
||
|
|
metadata: A metadata value to be passed to the service-side of
|
||
|
|
the RPC.
|
||
|
|
protocol_options: A value specified by the provider of a Face interface
|
||
|
|
implementation affording custom state and behavior.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
A single object that is both a Call object for the RPC and a
|
||
|
|
stream.Consumer to which the request values of the RPC should be passed.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
|
||
|
|
class StreamStreamMultiCallable(abc.ABC):
|
||
|
|
"""Affords invoking a stream-stream RPC in any call style."""
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def __call__(
|
||
|
|
self, request_iterator, timeout, metadata=None, protocol_options=None
|
||
|
|
):
|
||
|
|
"""Invokes the underlying RPC.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
request_iterator: An iterator that yields request values for the RPC.
|
||
|
|
timeout: A duration of time in seconds to allow for the RPC.
|
||
|
|
metadata: A metadata value to be passed to the service-side of
|
||
|
|
the RPC.
|
||
|
|
protocol_options: A value specified by the provider of a Face interface
|
||
|
|
implementation affording custom state and behavior.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
An object that is both a Call for the RPC and an iterator of response
|
||
|
|
values. Drawing response values from the returned iterator may raise
|
||
|
|
AbortionError indicating abortion of the RPC.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def event(
|
||
|
|
self,
|
||
|
|
receiver,
|
||
|
|
abortion_callback,
|
||
|
|
timeout,
|
||
|
|
metadata=None,
|
||
|
|
protocol_options=None,
|
||
|
|
):
|
||
|
|
"""Asynchronously invokes the underlying RPC.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
receiver: A ResponseReceiver to be passed the response data of the RPC.
|
||
|
|
abortion_callback: A callback to be called and passed an Abortion value
|
||
|
|
in the event of RPC abortion.
|
||
|
|
timeout: A duration of time in seconds to allow for the RPC.
|
||
|
|
metadata: A metadata value to be passed to the service-side of
|
||
|
|
the RPC.
|
||
|
|
protocol_options: A value specified by the provider of a Face interface
|
||
|
|
implementation affording custom state and behavior.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
A single object that is both a Call object for the RPC and a
|
||
|
|
stream.Consumer to which the request values of the RPC should be passed.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
|
||
|
|
class MethodImplementation(abc.ABC):
|
||
|
|
"""A sum type that describes a method implementation.
|
||
|
|
|
||
|
|
Attributes:
|
||
|
|
cardinality: A cardinality.Cardinality value.
|
||
|
|
style: A style.Service value.
|
||
|
|
unary_unary_inline: The implementation of the method as a callable value
|
||
|
|
that takes a request value and a ServicerContext object and returns a
|
||
|
|
response value. Only non-None if cardinality is
|
||
|
|
cardinality.Cardinality.UNARY_UNARY and style is style.Service.INLINE.
|
||
|
|
unary_stream_inline: The implementation of the method as a callable value
|
||
|
|
that takes a request value and a ServicerContext object and returns an
|
||
|
|
iterator of response values. Only non-None if cardinality is
|
||
|
|
cardinality.Cardinality.UNARY_STREAM and style is style.Service.INLINE.
|
||
|
|
stream_unary_inline: The implementation of the method as a callable value
|
||
|
|
that takes an iterator of request values and a ServicerContext object and
|
||
|
|
returns a response value. Only non-None if cardinality is
|
||
|
|
cardinality.Cardinality.STREAM_UNARY and style is style.Service.INLINE.
|
||
|
|
stream_stream_inline: The implementation of the method as a callable value
|
||
|
|
that takes an iterator of request values and a ServicerContext object and
|
||
|
|
returns an iterator of response values. Only non-None if cardinality is
|
||
|
|
cardinality.Cardinality.STREAM_STREAM and style is style.Service.INLINE.
|
||
|
|
unary_unary_event: The implementation of the method as a callable value that
|
||
|
|
takes a request value, a response callback to which to pass the response
|
||
|
|
value of the RPC, and a ServicerContext. Only non-None if cardinality is
|
||
|
|
cardinality.Cardinality.UNARY_UNARY and style is style.Service.EVENT.
|
||
|
|
unary_stream_event: The implementation of the method as a callable value
|
||
|
|
that takes a request value, a stream.Consumer to which to pass the
|
||
|
|
response values of the RPC, and a ServicerContext. Only non-None if
|
||
|
|
cardinality is cardinality.Cardinality.UNARY_STREAM and style is
|
||
|
|
style.Service.EVENT.
|
||
|
|
stream_unary_event: The implementation of the method as a callable value
|
||
|
|
that takes a response callback to which to pass the response value of the
|
||
|
|
RPC and a ServicerContext and returns a stream.Consumer to which the
|
||
|
|
request values of the RPC should be passed. Only non-None if cardinality
|
||
|
|
is cardinality.Cardinality.STREAM_UNARY and style is style.Service.EVENT.
|
||
|
|
stream_stream_event: The implementation of the method as a callable value
|
||
|
|
that takes a stream.Consumer to which to pass the response values of the
|
||
|
|
RPC and a ServicerContext and returns a stream.Consumer to which the
|
||
|
|
request values of the RPC should be passed. Only non-None if cardinality
|
||
|
|
is cardinality.Cardinality.STREAM_STREAM and style is
|
||
|
|
style.Service.EVENT.
|
||
|
|
"""
|
||
|
|
|
||
|
|
|
||
|
|
class MultiMethodImplementation(abc.ABC):
|
||
|
|
"""A general type able to service many methods."""
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def service(self, group, method, response_consumer, context):
|
||
|
|
"""Services an RPC.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
group: The group identifier of the RPC.
|
||
|
|
method: The method identifier of the RPC.
|
||
|
|
response_consumer: A stream.Consumer to be called to accept the response
|
||
|
|
values of the RPC.
|
||
|
|
context: a ServicerContext object.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
A stream.Consumer with which to accept the request values of the RPC. The
|
||
|
|
consumer returned from this method may or may not be invoked to
|
||
|
|
completion: in the case of RPC abortion, RPC Framework will simply stop
|
||
|
|
passing values to this object. Implementations must not assume that this
|
||
|
|
object will be called to completion of the request stream or even called
|
||
|
|
at all.
|
||
|
|
|
||
|
|
Raises:
|
||
|
|
abandonment.Abandoned: May or may not be raised when the RPC has been
|
||
|
|
aborted.
|
||
|
|
NoSuchMethodError: If this MultiMethod does not recognize the given group
|
||
|
|
and name for the RPC and is not able to service the RPC.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
|
||
|
|
class GenericStub(abc.ABC):
|
||
|
|
"""Affords RPC invocation via generic methods."""
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def blocking_unary_unary(
|
||
|
|
self,
|
||
|
|
group,
|
||
|
|
method,
|
||
|
|
request,
|
||
|
|
timeout,
|
||
|
|
metadata=None,
|
||
|
|
with_call=False,
|
||
|
|
protocol_options=None,
|
||
|
|
):
|
||
|
|
"""Invokes a unary-request-unary-response method.
|
||
|
|
|
||
|
|
This method blocks until either returning the response value of the RPC
|
||
|
|
(in the event of RPC completion) or raising an exception (in the event of
|
||
|
|
RPC abortion).
|
||
|
|
|
||
|
|
Args:
|
||
|
|
group: The group identifier of the RPC.
|
||
|
|
method: The method identifier of the RPC.
|
||
|
|
request: The request value for the RPC.
|
||
|
|
timeout: A duration of time in seconds to allow for the RPC.
|
||
|
|
metadata: A metadata value to be passed to the service-side of the RPC.
|
||
|
|
with_call: Whether or not to include return a Call for the RPC in addition
|
||
|
|
to the response.
|
||
|
|
protocol_options: A value specified by the provider of a Face interface
|
||
|
|
implementation affording custom state and behavior.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
The response value for the RPC, and a Call for the RPC if with_call was
|
||
|
|
set to True at invocation.
|
||
|
|
|
||
|
|
Raises:
|
||
|
|
AbortionError: Indicating that the RPC was aborted.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def future_unary_unary(
|
||
|
|
self,
|
||
|
|
group,
|
||
|
|
method,
|
||
|
|
request,
|
||
|
|
timeout,
|
||
|
|
metadata=None,
|
||
|
|
protocol_options=None,
|
||
|
|
):
|
||
|
|
"""Invokes a unary-request-unary-response method.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
group: The group identifier of the RPC.
|
||
|
|
method: The method identifier of the RPC.
|
||
|
|
request: The request value for the RPC.
|
||
|
|
timeout: A duration of time in seconds to allow for the RPC.
|
||
|
|
metadata: A metadata value to be passed to the service-side of the RPC.
|
||
|
|
protocol_options: A value specified by the provider of a Face interface
|
||
|
|
implementation affording custom state and behavior.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
An object that is both a Call for the RPC and a future.Future. In the
|
||
|
|
event of RPC completion, the return Future's result value will be the
|
||
|
|
response value of the RPC. In the event of RPC abortion, the returned
|
||
|
|
Future's exception value will be an AbortionError.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def inline_unary_stream(
|
||
|
|
self,
|
||
|
|
group,
|
||
|
|
method,
|
||
|
|
request,
|
||
|
|
timeout,
|
||
|
|
metadata=None,
|
||
|
|
protocol_options=None,
|
||
|
|
):
|
||
|
|
"""Invokes a unary-request-stream-response method.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
group: The group identifier of the RPC.
|
||
|
|
method: The method identifier of the RPC.
|
||
|
|
request: The request value for the RPC.
|
||
|
|
timeout: A duration of time in seconds to allow for the RPC.
|
||
|
|
metadata: A metadata value to be passed to the service-side of the RPC.
|
||
|
|
protocol_options: A value specified by the provider of a Face interface
|
||
|
|
implementation affording custom state and behavior.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
An object that is both a Call for the RPC and an iterator of response
|
||
|
|
values. Drawing response values from the returned iterator may raise
|
||
|
|
AbortionError indicating abortion of the RPC.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def blocking_stream_unary(
|
||
|
|
self,
|
||
|
|
group,
|
||
|
|
method,
|
||
|
|
request_iterator,
|
||
|
|
timeout,
|
||
|
|
metadata=None,
|
||
|
|
with_call=False,
|
||
|
|
protocol_options=None,
|
||
|
|
):
|
||
|
|
"""Invokes a stream-request-unary-response method.
|
||
|
|
|
||
|
|
This method blocks until either returning the response value of the RPC
|
||
|
|
(in the event of RPC completion) or raising an exception (in the event of
|
||
|
|
RPC abortion).
|
||
|
|
|
||
|
|
Args:
|
||
|
|
group: The group identifier of the RPC.
|
||
|
|
method: The method identifier of the RPC.
|
||
|
|
request_iterator: An iterator that yields request values for the RPC.
|
||
|
|
timeout: A duration of time in seconds to allow for the RPC.
|
||
|
|
metadata: A metadata value to be passed to the service-side of the RPC.
|
||
|
|
with_call: Whether or not to include return a Call for the RPC in addition
|
||
|
|
to the response.
|
||
|
|
protocol_options: A value specified by the provider of a Face interface
|
||
|
|
implementation affording custom state and behavior.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
The response value for the RPC, and a Call for the RPC if with_call was
|
||
|
|
set to True at invocation.
|
||
|
|
|
||
|
|
Raises:
|
||
|
|
AbortionError: Indicating that the RPC was aborted.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def future_stream_unary(
|
||
|
|
self,
|
||
|
|
group,
|
||
|
|
method,
|
||
|
|
request_iterator,
|
||
|
|
timeout,
|
||
|
|
metadata=None,
|
||
|
|
protocol_options=None,
|
||
|
|
):
|
||
|
|
"""Invokes a stream-request-unary-response method.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
group: The group identifier of the RPC.
|
||
|
|
method: The method identifier of the RPC.
|
||
|
|
request_iterator: An iterator that yields request values for the RPC.
|
||
|
|
timeout: A duration of time in seconds to allow for the RPC.
|
||
|
|
metadata: A metadata value to be passed to the service-side of the RPC.
|
||
|
|
protocol_options: A value specified by the provider of a Face interface
|
||
|
|
implementation affording custom state and behavior.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
An object that is both a Call for the RPC and a future.Future. In the
|
||
|
|
event of RPC completion, the return Future's result value will be the
|
||
|
|
response value of the RPC. In the event of RPC abortion, the returned
|
||
|
|
Future's exception value will be an AbortionError.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def inline_stream_stream(
|
||
|
|
self,
|
||
|
|
group,
|
||
|
|
method,
|
||
|
|
request_iterator,
|
||
|
|
timeout,
|
||
|
|
metadata=None,
|
||
|
|
protocol_options=None,
|
||
|
|
):
|
||
|
|
"""Invokes a stream-request-stream-response method.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
group: The group identifier of the RPC.
|
||
|
|
method: The method identifier of the RPC.
|
||
|
|
request_iterator: An iterator that yields request values for the RPC.
|
||
|
|
timeout: A duration of time in seconds to allow for the RPC.
|
||
|
|
metadata: A metadata value to be passed to the service-side of the RPC.
|
||
|
|
protocol_options: A value specified by the provider of a Face interface
|
||
|
|
implementation affording custom state and behavior.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
An object that is both a Call for the RPC and an iterator of response
|
||
|
|
values. Drawing response values from the returned iterator may raise
|
||
|
|
AbortionError indicating abortion of the RPC.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def event_unary_unary(
|
||
|
|
self,
|
||
|
|
group,
|
||
|
|
method,
|
||
|
|
request,
|
||
|
|
receiver,
|
||
|
|
abortion_callback,
|
||
|
|
timeout,
|
||
|
|
metadata=None,
|
||
|
|
protocol_options=None,
|
||
|
|
):
|
||
|
|
"""Event-driven invocation of a unary-request-unary-response method.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
group: The group identifier of the RPC.
|
||
|
|
method: The method identifier of the RPC.
|
||
|
|
request: The request value for the RPC.
|
||
|
|
receiver: A ResponseReceiver to be passed the response data of the RPC.
|
||
|
|
abortion_callback: A callback to be called and passed an Abortion value
|
||
|
|
in the event of RPC abortion.
|
||
|
|
timeout: A duration of time in seconds to allow for the RPC.
|
||
|
|
metadata: A metadata value to be passed to the service-side of the RPC.
|
||
|
|
protocol_options: A value specified by the provider of a Face interface
|
||
|
|
implementation affording custom state and behavior.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
A Call for the RPC.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def event_unary_stream(
|
||
|
|
self,
|
||
|
|
group,
|
||
|
|
method,
|
||
|
|
request,
|
||
|
|
receiver,
|
||
|
|
abortion_callback,
|
||
|
|
timeout,
|
||
|
|
metadata=None,
|
||
|
|
protocol_options=None,
|
||
|
|
):
|
||
|
|
"""Event-driven invocation of a unary-request-stream-response method.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
group: The group identifier of the RPC.
|
||
|
|
method: The method identifier of the RPC.
|
||
|
|
request: The request value for the RPC.
|
||
|
|
receiver: A ResponseReceiver to be passed the response data of the RPC.
|
||
|
|
abortion_callback: A callback to be called and passed an Abortion value
|
||
|
|
in the event of RPC abortion.
|
||
|
|
timeout: A duration of time in seconds to allow for the RPC.
|
||
|
|
metadata: A metadata value to be passed to the service-side of the RPC.
|
||
|
|
protocol_options: A value specified by the provider of a Face interface
|
||
|
|
implementation affording custom state and behavior.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
A Call for the RPC.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def event_stream_unary(
|
||
|
|
self,
|
||
|
|
group,
|
||
|
|
method,
|
||
|
|
receiver,
|
||
|
|
abortion_callback,
|
||
|
|
timeout,
|
||
|
|
metadata=None,
|
||
|
|
protocol_options=None,
|
||
|
|
):
|
||
|
|
"""Event-driven invocation of a unary-request-unary-response method.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
group: The group identifier of the RPC.
|
||
|
|
method: The method identifier of the RPC.
|
||
|
|
receiver: A ResponseReceiver to be passed the response data of the RPC.
|
||
|
|
abortion_callback: A callback to be called and passed an Abortion value
|
||
|
|
in the event of RPC abortion.
|
||
|
|
timeout: A duration of time in seconds to allow for the RPC.
|
||
|
|
metadata: A metadata value to be passed to the service-side of the RPC.
|
||
|
|
protocol_options: A value specified by the provider of a Face interface
|
||
|
|
implementation affording custom state and behavior.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
A pair of a Call object for the RPC and a stream.Consumer to which the
|
||
|
|
request values of the RPC should be passed.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def event_stream_stream(
|
||
|
|
self,
|
||
|
|
group,
|
||
|
|
method,
|
||
|
|
receiver,
|
||
|
|
abortion_callback,
|
||
|
|
timeout,
|
||
|
|
metadata=None,
|
||
|
|
protocol_options=None,
|
||
|
|
):
|
||
|
|
"""Event-driven invocation of a unary-request-stream-response method.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
group: The group identifier of the RPC.
|
||
|
|
method: The method identifier of the RPC.
|
||
|
|
receiver: A ResponseReceiver to be passed the response data of the RPC.
|
||
|
|
abortion_callback: A callback to be called and passed an Abortion value
|
||
|
|
in the event of RPC abortion.
|
||
|
|
timeout: A duration of time in seconds to allow for the RPC.
|
||
|
|
metadata: A metadata value to be passed to the service-side of the RPC.
|
||
|
|
protocol_options: A value specified by the provider of a Face interface
|
||
|
|
implementation affording custom state and behavior.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
A pair of a Call object for the RPC and a stream.Consumer to which the
|
||
|
|
request values of the RPC should be passed.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def unary_unary(self, group, method):
|
||
|
|
"""Creates a UnaryUnaryMultiCallable for a unary-unary method.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
group: The group identifier of the RPC.
|
||
|
|
method: The method identifier of the RPC.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
A UnaryUnaryMultiCallable value for the named unary-unary method.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def unary_stream(self, group, method):
|
||
|
|
"""Creates a UnaryStreamMultiCallable for a unary-stream method.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
group: The group identifier of the RPC.
|
||
|
|
method: The method identifier of the RPC.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
A UnaryStreamMultiCallable value for the name unary-stream method.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def stream_unary(self, group, method):
|
||
|
|
"""Creates a StreamUnaryMultiCallable for a stream-unary method.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
group: The group identifier of the RPC.
|
||
|
|
method: The method identifier of the RPC.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
A StreamUnaryMultiCallable value for the named stream-unary method.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
@abc.abstractmethod
|
||
|
|
def stream_stream(self, group, method):
|
||
|
|
"""Creates a StreamStreamMultiCallable for a stream-stream method.
|
||
|
|
|
||
|
|
Args:
|
||
|
|
group: The group identifier of the RPC.
|
||
|
|
method: The method identifier of the RPC.
|
||
|
|
|
||
|
|
Returns:
|
||
|
|
A StreamStreamMultiCallable value for the named stream-stream method.
|
||
|
|
"""
|
||
|
|
raise NotImplementedError()
|
||
|
|
|
||
|
|
|
||
|
|
class DynamicStub(abc.ABC):
|
||
|
|
"""Affords RPC invocation via attributes corresponding to afforded methods.
|
||
|
|
|
||
|
|
Instances of this type may be scoped to a single group so that attribute
|
||
|
|
access is unambiguous.
|
||
|
|
|
||
|
|
Instances of this type respond to attribute access as follows: if the
|
||
|
|
requested attribute is the name of a unary-unary method, the value of the
|
||
|
|
attribute will be a UnaryUnaryMultiCallable with which to invoke an RPC; if
|
||
|
|
the requested attribute is the name of a unary-stream method, the value of the
|
||
|
|
attribute will be a UnaryStreamMultiCallable with which to invoke an RPC; if
|
||
|
|
the requested attribute is the name of a stream-unary method, the value of the
|
||
|
|
attribute will be a StreamUnaryMultiCallable with which to invoke an RPC; and
|
||
|
|
if the requested attribute is the name of a stream-stream method, the value of
|
||
|
|
the attribute will be a StreamStreamMultiCallable with which to invoke an RPC.
|
||
|
|
"""
|