# Copyright 2019 gRPC authors.
#
# 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.
"""Interceptors implementation of gRPC Asyncio Python."""
from abc import ABCMeta
from abc import abstractmethod
import asyncio
import collections
import functools
from typing import (
AsyncIterable,
Awaitable,
Callable,
Iterator,
List,
Optional,
Sequence,
Union,
)
import grpc
from grpc._cython import cygrpc
from . import _base_call
from ._call import AioRpcError
from ._call import StreamStreamCall
from ._call import StreamUnaryCall
from ._call import UnaryStreamCall
from ._call import UnaryUnaryCall
from ._call import _API_STYLE_ERROR
from ._call import _RPC_ALREADY_FINISHED_DETAILS
from ._call import _RPC_HALF_CLOSED_DETAILS
from ._metadata import Metadata
from ._typing import DeserializingFunction
from ._typing import DoneCallbackType
from ._typing import RequestIterableType
from ._typing import RequestType
from ._typing import ResponseIterableType
from ._typing import ResponseType
from ._typing import SerializingFunction
from ._utils import _timeout_to_deadline
_LOCAL_CANCELLATION_DETAILS = "Locally cancelled by application!"
[docs]class ServerInterceptor(metaclass=ABCMeta):
"""Affords intercepting incoming RPCs on the service-side.
This is an EXPERIMENTAL API.
"""
[docs] @abstractmethod
async def intercept_service(
self,
continuation: Callable[
[grpc.HandlerCallDetails], Awaitable[grpc.RpcMethodHandler]
],
handler_call_details: grpc.HandlerCallDetails,
) -> grpc.RpcMethodHandler:
"""Intercepts incoming RPCs before handing them over to a handler.
State can be passed from an interceptor to downstream interceptors
via contextvars. The first interceptor is called from an empty
contextvars.Context, and the same Context is used for downstream
interceptors and for the final handler call. Note that there are no
guarantees that interceptors and handlers will be called from the
same thread.
Args:
continuation: A function that takes a HandlerCallDetails and
proceeds to invoke the next interceptor in the chain, if any,
or the RPC handler lookup logic, with the call details passed
as an argument, and returns an RpcMethodHandler instance if
the RPC is considered serviced, or None otherwise.
handler_call_details: A HandlerCallDetails describing the RPC.
Returns:
An RpcMethodHandler with which the RPC may be serviced if the
interceptor chooses to service this RPC, or None otherwise.
"""
[docs]class ClientCallDetails(
collections.namedtuple(
"ClientCallDetails",
("method", "timeout", "metadata", "credentials", "wait_for_ready"),
),
grpc.ClientCallDetails,
):
"""Describes an RPC to be invoked.
This is an EXPERIMENTAL API.
Args:
method: The method name of the RPC.
timeout: An optional duration of time in seconds to allow for the RPC.
metadata: Optional metadata to be transmitted to the service-side of
the RPC.
credentials: An optional CallCredentials for the RPC.
wait_for_ready: An optional flag to enable :term:`wait_for_ready` mechanism.
"""
method: str
timeout: Optional[float]
metadata: Optional[Metadata]
credentials: Optional[grpc.CallCredentials]
wait_for_ready: Optional[bool]
[docs]class ClientInterceptor(metaclass=ABCMeta):
"""Base class used for all Aio Client Interceptor classes"""
[docs]class UnaryUnaryClientInterceptor(ClientInterceptor, metaclass=ABCMeta):
"""Affords intercepting unary-unary invocations."""
[docs] @abstractmethod
async def intercept_unary_unary(
self,
continuation: Callable[
[ClientCallDetails, RequestType], UnaryUnaryCall
],
client_call_details: ClientCallDetails,
request: RequestType,
) -> Union[UnaryUnaryCall, ResponseType]:
"""Intercepts a unary-unary invocation asynchronously.
Args:
continuation: A coroutine that proceeds with the invocation by
executing the next interceptor in the chain or invoking the
actual RPC on the underlying Channel. It is the interceptor's
responsibility to call it if it decides to move the RPC forward.
The interceptor can use
`call = await continuation(client_call_details, request)`
to continue with the RPC. `continuation` returns the call to the
RPC.
client_call_details: A ClientCallDetails object describing the
outgoing RPC.
request: The request value for the RPC.
Returns:
An object with the RPC response.
Raises:
AioRpcError: Indicating that the RPC terminated with non-OK status.
asyncio.CancelledError: Indicating that the RPC was canceled.
"""
[docs]class UnaryStreamClientInterceptor(ClientInterceptor, metaclass=ABCMeta):
"""Affords intercepting unary-stream invocations."""
[docs] @abstractmethod
async def intercept_unary_stream(
self,
continuation: Callable[
[ClientCallDetails, RequestType], UnaryStreamCall
],
client_call_details: ClientCallDetails,
request: RequestType,
) -> Union[ResponseIterableType, UnaryStreamCall]:
"""Intercepts a unary-stream invocation asynchronously.
The function could return the call object or an asynchronous
iterator, in case of being an asyncrhonous iterator this will
become the source of the reads done by the caller.
Args:
continuation: A coroutine that proceeds with the invocation by
executing the next interceptor in the chain or invoking the
actual RPC on the underlying Channel. It is the interceptor's
responsibility to call it if it decides to move the RPC forward.
The interceptor can use
`call = await continuation(client_call_details, request)`
to continue with the RPC. `continuation` returns the call to the
RPC.
client_call_details: A ClientCallDetails object describing the
outgoing RPC.
request: The request value for the RPC.
Returns:
The RPC Call or an asynchronous iterator.
Raises:
AioRpcError: Indicating that the RPC terminated with non-OK status.
asyncio.CancelledError: Indicating that the RPC was canceled.
"""
[docs]class StreamUnaryClientInterceptor(ClientInterceptor, metaclass=ABCMeta):
"""Affords intercepting stream-unary invocations."""
[docs] @abstractmethod
async def intercept_stream_unary(
self,
continuation: Callable[
[ClientCallDetails, RequestType], StreamUnaryCall
],
client_call_details: ClientCallDetails,
request_iterator: RequestIterableType,
) -> StreamUnaryCall:
"""Intercepts a stream-unary invocation asynchronously.
Within the interceptor the usage of the call methods like `write` or
even awaiting the call should be done carefully, since the caller
could be expecting an untouched call, for example for start writing
messages to it.
Args:
continuation: A coroutine that proceeds with the invocation by
executing the next interceptor in the chain or invoking the
actual RPC on the underlying Channel. It is the interceptor's
responsibility to call it if it decides to move the RPC forward.
The interceptor can use
`call = await continuation(client_call_details, request_iterator)`
to continue with the RPC. `continuation` returns the call to the
RPC.
client_call_details: A ClientCallDetails object describing the
outgoing RPC.
request_iterator: The request iterator that will produce requests
for the RPC.
Returns:
The RPC Call.
Raises:
AioRpcError: Indicating that the RPC terminated with non-OK status.
asyncio.CancelledError: Indicating that the RPC was canceled.
"""
[docs]class StreamStreamClientInterceptor(ClientInterceptor, metaclass=ABCMeta):
"""Affords intercepting stream-stream invocations."""
[docs] @abstractmethod
async def intercept_stream_stream(
self,
continuation: Callable[
[ClientCallDetails, RequestType], StreamStreamCall
],
client_call_details: ClientCallDetails,
request_iterator: RequestIterableType,
) -> Union[ResponseIterableType, StreamStreamCall]:
"""Intercepts a stream-stream invocation asynchronously.
Within the interceptor the usage of the call methods like `write` or
even awaiting the call should be done carefully, since the caller
could be expecting an untouched call, for example for start writing
messages to it.
The function could return the call object or an asynchronous
iterator, in case of being an asyncrhonous iterator this will
become the source of the reads done by the caller.
Args:
continuation: A coroutine that proceeds with the invocation by
executing the next interceptor in the chain or invoking the
actual RPC on the underlying Channel. It is the interceptor's
responsibility to call it if it decides to move the RPC forward.
The interceptor can use
`call = await continuation(client_call_details, request_iterator)`
to continue with the RPC. `continuation` returns the call to the
RPC.
client_call_details: A ClientCallDetails object describing the
outgoing RPC.
request_iterator: The request iterator that will produce requests
for the RPC.
Returns:
The RPC Call or an asynchronous iterator.
Raises:
AioRpcError: Indicating that the RPC terminated with non-OK status.
asyncio.CancelledError: Indicating that the RPC was canceled.
"""
class InterceptedCall:
"""Base implementation for all intercepted call arities.
Interceptors might have some work to do before the RPC invocation with
the capacity of changing the invocation parameters, and some work to do
after the RPC invocation with the capacity for accessing to the wrapped
`UnaryUnaryCall`.
It handles also early and later cancellations, when the RPC has not even
started and the execution is still held by the interceptors or when the
RPC has finished but again the execution is still held by the interceptors.
Once the RPC is finally executed, all methods are finally done against the
intercepted call, being at the same time the same call returned to the
interceptors.
As a base class for all of the interceptors implements the logic around
final status, metadata and cancellation.
"""
_interceptors_task: asyncio.Task
_pending_add_done_callbacks: Sequence[DoneCallbackType]
def __init__(self, interceptors_task: asyncio.Task) -> None:
self._interceptors_task = interceptors_task
self._pending_add_done_callbacks = []
self._interceptors_task.add_done_callback(
self._fire_or_add_pending_done_callbacks
)
def __del__(self):
self.cancel()
def _fire_or_add_pending_done_callbacks(
self, interceptors_task: asyncio.Task
) -> None:
if not self._pending_add_done_callbacks:
return
call_completed = False
try:
call = interceptors_task.result()
if call.done():
call_completed = True
except (AioRpcError, asyncio.CancelledError):
call_completed = True
if call_completed:
for callback in self._pending_add_done_callbacks:
callback(self)
else:
for callback in self._pending_add_done_callbacks:
callback = functools.partial(
self._wrap_add_done_callback, callback
)
call.add_done_callback(callback)
self._pending_add_done_callbacks = []
def _wrap_add_done_callback(
self, callback: DoneCallbackType, unused_call: _base_call.Call
) -> None:
callback(self)
def cancel(self) -> bool:
if not self._interceptors_task.done():
# There is no yet the intercepted call available,
# Trying to cancel it by using the generic Asyncio
# cancellation method.
return self._interceptors_task.cancel()
try:
call = self._interceptors_task.result()
except AioRpcError:
return False
except asyncio.CancelledError:
return False
return call.cancel()
def cancelled(self) -> bool:
if not self._interceptors_task.done():
return False
try:
call = self._interceptors_task.result()
except AioRpcError as err:
return err.code() == grpc.StatusCode.CANCELLED
except asyncio.CancelledError:
return True
return call.cancelled()
def done(self) -> bool:
if not self._interceptors_task.done():
return False
try:
call = self._interceptors_task.result()
except (AioRpcError, asyncio.CancelledError):
return True
return call.done()
def add_done_callback(self, callback: DoneCallbackType) -> None:
if not self._interceptors_task.done():
self._pending_add_done_callbacks.append(callback)
return
try:
call = self._interceptors_task.result()
except (AioRpcError, asyncio.CancelledError):
callback(self)
return
if call.done():
callback(self)
else:
callback = functools.partial(self._wrap_add_done_callback, callback)
call.add_done_callback(callback)
def time_remaining(self) -> Optional[float]:
raise NotImplementedError()
async def initial_metadata(self) -> Optional[Metadata]:
try:
call = await self._interceptors_task
except AioRpcError as err:
return err.initial_metadata()
except asyncio.CancelledError:
return None
return await call.initial_metadata()
async def trailing_metadata(self) -> Optional[Metadata]:
try:
call = await self._interceptors_task
except AioRpcError as err:
return err.trailing_metadata()
except asyncio.CancelledError:
return None
return await call.trailing_metadata()
async def code(self) -> grpc.StatusCode:
try:
call = await self._interceptors_task
except AioRpcError as err:
return err.code()
except asyncio.CancelledError:
return grpc.StatusCode.CANCELLED
return await call.code()
async def details(self) -> str:
try:
call = await self._interceptors_task
except AioRpcError as err:
return err.details()
except asyncio.CancelledError:
return _LOCAL_CANCELLATION_DETAILS
return await call.details()
async def debug_error_string(self) -> Optional[str]:
try:
call = await self._interceptors_task
except AioRpcError as err:
return err.debug_error_string()
except asyncio.CancelledError:
return ""
return await call.debug_error_string()
async def wait_for_connection(self) -> None:
call = await self._interceptors_task
return await call.wait_for_connection()
class _InterceptedUnaryResponseMixin:
def __await__(self):
call = yield from self._interceptors_task.__await__()
response = yield from call.__await__()
return response
class _InterceptedStreamResponseMixin:
_response_aiter: Optional[AsyncIterable[ResponseType]]
def _init_stream_response_mixin(self) -> None:
# Is initalized later, otherwise if the iterator is not finnally
# consumed a logging warning is emmited by Asyncio.
self._response_aiter = None
async def _wait_for_interceptor_task_response_iterator(
self,
) -> ResponseType:
call = await self._interceptors_task
async for response in call:
yield response
def __aiter__(self) -> AsyncIterable[ResponseType]:
if self._response_aiter is None:
self._response_aiter = (
self._wait_for_interceptor_task_response_iterator()
)
return self._response_aiter
async def read(self) -> ResponseType:
if self._response_aiter is None:
self._response_aiter = (
self._wait_for_interceptor_task_response_iterator()
)
return await self._response_aiter.asend(None)
class _InterceptedStreamRequestMixin:
_write_to_iterator_async_gen: Optional[AsyncIterable[RequestType]]
_write_to_iterator_queue: Optional[asyncio.Queue]
_status_code_task: Optional[asyncio.Task]
_FINISH_ITERATOR_SENTINEL = object()
def _init_stream_request_mixin(
self, request_iterator: Optional[RequestIterableType]
) -> RequestIterableType:
if request_iterator is None:
# We provide our own request iterator which is a proxy
# of the futures writes that will be done by the caller.
self._write_to_iterator_queue = asyncio.Queue(maxsize=1)
self._write_to_iterator_async_gen = (
self._proxy_writes_as_request_iterator()
)
self._status_code_task = None
request_iterator = self._write_to_iterator_async_gen
else:
self._write_to_iterator_queue = None
return request_iterator
async def _proxy_writes_as_request_iterator(self):
await self._interceptors_task
while True:
value = await self._write_to_iterator_queue.get()
if (
value
is _InterceptedStreamRequestMixin._FINISH_ITERATOR_SENTINEL
):
break
yield value
async def _write_to_iterator_queue_interruptible(
self, request: RequestType, call: InterceptedCall
):
# Write the specified 'request' to the request iterator queue using the
# specified 'call' to allow for interruption of the write in the case
# of abrupt termination of the call.
if self._status_code_task is None:
self._status_code_task = self._loop.create_task(call.code())
await asyncio.wait(
(
self._loop.create_task(
self._write_to_iterator_queue.put(request)
),
self._status_code_task,
),
return_when=asyncio.FIRST_COMPLETED,
)
async def write(self, request: RequestType) -> None:
# If no queue was created it means that requests
# should be expected through an iterators provided
# by the caller.
if self._write_to_iterator_queue is None:
raise cygrpc.UsageError(_API_STYLE_ERROR)
try:
call = await self._interceptors_task
except (asyncio.CancelledError, AioRpcError):
raise asyncio.InvalidStateError(_RPC_ALREADY_FINISHED_DETAILS)
if call.done():
raise asyncio.InvalidStateError(_RPC_ALREADY_FINISHED_DETAILS)
elif call._done_writing_flag:
raise asyncio.InvalidStateError(_RPC_HALF_CLOSED_DETAILS)
await self._write_to_iterator_queue_interruptible(request, call)
if call.done():
raise asyncio.InvalidStateError(_RPC_ALREADY_FINISHED_DETAILS)
async def done_writing(self) -> None:
"""Signal peer that client is done writing.
This method is idempotent.
"""
# If no queue was created it means that requests
# should be expected through an iterators provided
# by the caller.
if self._write_to_iterator_queue is None:
raise cygrpc.UsageError(_API_STYLE_ERROR)
try:
call = await self._interceptors_task
except asyncio.CancelledError:
raise asyncio.InvalidStateError(_RPC_ALREADY_FINISHED_DETAILS)
await self._write_to_iterator_queue_interruptible(
_InterceptedStreamRequestMixin._FINISH_ITERATOR_SENTINEL, call
)
[docs]class InterceptedUnaryUnaryCall(
_InterceptedUnaryResponseMixin, InterceptedCall, _base_call.UnaryUnaryCall
):
"""Used for running a `UnaryUnaryCall` wrapped by interceptors.
For the `__await__` method is it is proxied to the intercepted call only when
the interceptor task is finished.
"""
_loop: asyncio.AbstractEventLoop
_channel: cygrpc.AioChannel
# pylint: disable=too-many-arguments
def __init__(
self,
interceptors: Sequence[UnaryUnaryClientInterceptor],
request: RequestType,
timeout: Optional[float],
metadata: Metadata,
credentials: Optional[grpc.CallCredentials],
wait_for_ready: Optional[bool],
channel: cygrpc.AioChannel,
method: bytes,
request_serializer: SerializingFunction,
response_deserializer: DeserializingFunction,
loop: asyncio.AbstractEventLoop,
) -> None:
self._loop = loop
self._channel = channel
interceptors_task = loop.create_task(
self._invoke(
interceptors,
method,
timeout,
metadata,
credentials,
wait_for_ready,
request,
request_serializer,
response_deserializer,
)
)
super().__init__(interceptors_task)
# pylint: disable=too-many-arguments
async def _invoke(
self,
interceptors: Sequence[UnaryUnaryClientInterceptor],
method: bytes,
timeout: Optional[float],
metadata: Optional[Metadata],
credentials: Optional[grpc.CallCredentials],
wait_for_ready: Optional[bool],
request: RequestType,
request_serializer: SerializingFunction,
response_deserializer: DeserializingFunction,
) -> UnaryUnaryCall:
"""Run the RPC call wrapped in interceptors"""
async def _run_interceptor(
interceptors: List[UnaryUnaryClientInterceptor],
client_call_details: ClientCallDetails,
request: RequestType,
) -> _base_call.UnaryUnaryCall:
if interceptors:
continuation = functools.partial(
_run_interceptor, interceptors[1:]
)
call_or_response = await interceptors[0].intercept_unary_unary(
continuation, client_call_details, request
)
if isinstance(call_or_response, _base_call.UnaryUnaryCall):
return call_or_response
else:
return UnaryUnaryCallResponse(call_or_response)
else:
return UnaryUnaryCall(
request,
_timeout_to_deadline(client_call_details.timeout),
client_call_details.metadata,
client_call_details.credentials,
client_call_details.wait_for_ready,
self._channel,
client_call_details.method,
request_serializer,
response_deserializer,
self._loop,
)
client_call_details = ClientCallDetails(
method, timeout, metadata, credentials, wait_for_ready
)
return await _run_interceptor(
list(interceptors), client_call_details, request
)
[docs] def time_remaining(self) -> Optional[float]:
raise NotImplementedError()
class InterceptedUnaryStreamCall(
_InterceptedStreamResponseMixin, InterceptedCall, _base_call.UnaryStreamCall
):
"""Used for running a `UnaryStreamCall` wrapped by interceptors."""
_loop: asyncio.AbstractEventLoop
_channel: cygrpc.AioChannel
_last_returned_call_from_interceptors = Optional[_base_call.UnaryStreamCall]
# pylint: disable=too-many-arguments
def __init__(
self,
interceptors: Sequence[UnaryStreamClientInterceptor],
request: RequestType,
timeout: Optional[float],
metadata: Metadata,
credentials: Optional[grpc.CallCredentials],
wait_for_ready: Optional[bool],
channel: cygrpc.AioChannel,
method: bytes,
request_serializer: SerializingFunction,
response_deserializer: DeserializingFunction,
loop: asyncio.AbstractEventLoop,
) -> None:
self._loop = loop
self._channel = channel
self._init_stream_response_mixin()
self._last_returned_call_from_interceptors = None
interceptors_task = loop.create_task(
self._invoke(
interceptors,
method,
timeout,
metadata,
credentials,
wait_for_ready,
request,
request_serializer,
response_deserializer,
)
)
super().__init__(interceptors_task)
# pylint: disable=too-many-arguments
async def _invoke(
self,
interceptors: Sequence[UnaryStreamClientInterceptor],
method: bytes,
timeout: Optional[float],
metadata: Optional[Metadata],
credentials: Optional[grpc.CallCredentials],
wait_for_ready: Optional[bool],
request: RequestType,
request_serializer: SerializingFunction,
response_deserializer: DeserializingFunction,
) -> UnaryStreamCall:
"""Run the RPC call wrapped in interceptors"""
async def _run_interceptor(
interceptors: List[UnaryStreamClientInterceptor],
client_call_details: ClientCallDetails,
request: RequestType,
) -> _base_call.UnaryStreamCall:
if interceptors:
continuation = functools.partial(
_run_interceptor, interceptors[1:]
)
call_or_response_iterator = await interceptors[
0
].intercept_unary_stream(
continuation, client_call_details, request
)
if isinstance(
call_or_response_iterator, _base_call.UnaryStreamCall
):
self._last_returned_call_from_interceptors = (
call_or_response_iterator
)
else:
self._last_returned_call_from_interceptors = (
UnaryStreamCallResponseIterator(
self._last_returned_call_from_interceptors,
call_or_response_iterator,
)
)
return self._last_returned_call_from_interceptors
else:
self._last_returned_call_from_interceptors = UnaryStreamCall(
request,
_timeout_to_deadline(client_call_details.timeout),
client_call_details.metadata,
client_call_details.credentials,
client_call_details.wait_for_ready,
self._channel,
client_call_details.method,
request_serializer,
response_deserializer,
self._loop,
)
return self._last_returned_call_from_interceptors
client_call_details = ClientCallDetails(
method, timeout, metadata, credentials, wait_for_ready
)
return await _run_interceptor(
list(interceptors), client_call_details, request
)
def time_remaining(self) -> Optional[float]:
raise NotImplementedError()
class InterceptedStreamUnaryCall(
_InterceptedUnaryResponseMixin,
_InterceptedStreamRequestMixin,
InterceptedCall,
_base_call.StreamUnaryCall,
):
"""Used for running a `StreamUnaryCall` wrapped by interceptors.
For the `__await__` method is it is proxied to the intercepted call only when
the interceptor task is finished.
"""
_loop: asyncio.AbstractEventLoop
_channel: cygrpc.AioChannel
# pylint: disable=too-many-arguments
def __init__(
self,
interceptors: Sequence[StreamUnaryClientInterceptor],
request_iterator: Optional[RequestIterableType],
timeout: Optional[float],
metadata: Metadata,
credentials: Optional[grpc.CallCredentials],
wait_for_ready: Optional[bool],
channel: cygrpc.AioChannel,
method: bytes,
request_serializer: SerializingFunction,
response_deserializer: DeserializingFunction,
loop: asyncio.AbstractEventLoop,
) -> None:
self._loop = loop
self._channel = channel
request_iterator = self._init_stream_request_mixin(request_iterator)
interceptors_task = loop.create_task(
self._invoke(
interceptors,
method,
timeout,
metadata,
credentials,
wait_for_ready,
request_iterator,
request_serializer,
response_deserializer,
)
)
super().__init__(interceptors_task)
# pylint: disable=too-many-arguments
async def _invoke(
self,
interceptors: Sequence[StreamUnaryClientInterceptor],
method: bytes,
timeout: Optional[float],
metadata: Optional[Metadata],
credentials: Optional[grpc.CallCredentials],
wait_for_ready: Optional[bool],
request_iterator: RequestIterableType,
request_serializer: SerializingFunction,
response_deserializer: DeserializingFunction,
) -> StreamUnaryCall:
"""Run the RPC call wrapped in interceptors"""
async def _run_interceptor(
interceptors: Iterator[StreamUnaryClientInterceptor],
client_call_details: ClientCallDetails,
request_iterator: RequestIterableType,
) -> _base_call.StreamUnaryCall:
if interceptors:
continuation = functools.partial(
_run_interceptor, interceptors[1:]
)
return await interceptors[0].intercept_stream_unary(
continuation, client_call_details, request_iterator
)
else:
return StreamUnaryCall(
request_iterator,
_timeout_to_deadline(client_call_details.timeout),
client_call_details.metadata,
client_call_details.credentials,
client_call_details.wait_for_ready,
self._channel,
client_call_details.method,
request_serializer,
response_deserializer,
self._loop,
)
client_call_details = ClientCallDetails(
method, timeout, metadata, credentials, wait_for_ready
)
return await _run_interceptor(
list(interceptors), client_call_details, request_iterator
)
def time_remaining(self) -> Optional[float]:
raise NotImplementedError()
class InterceptedStreamStreamCall(
_InterceptedStreamResponseMixin,
_InterceptedStreamRequestMixin,
InterceptedCall,
_base_call.StreamStreamCall,
):
"""Used for running a `StreamStreamCall` wrapped by interceptors."""
_loop: asyncio.AbstractEventLoop
_channel: cygrpc.AioChannel
_last_returned_call_from_interceptors = Optional[
_base_call.StreamStreamCall
]
# pylint: disable=too-many-arguments
def __init__(
self,
interceptors: Sequence[StreamStreamClientInterceptor],
request_iterator: Optional[RequestIterableType],
timeout: Optional[float],
metadata: Metadata,
credentials: Optional[grpc.CallCredentials],
wait_for_ready: Optional[bool],
channel: cygrpc.AioChannel,
method: bytes,
request_serializer: SerializingFunction,
response_deserializer: DeserializingFunction,
loop: asyncio.AbstractEventLoop,
) -> None:
self._loop = loop
self._channel = channel
self._init_stream_response_mixin()
request_iterator = self._init_stream_request_mixin(request_iterator)
self._last_returned_call_from_interceptors = None
interceptors_task = loop.create_task(
self._invoke(
interceptors,
method,
timeout,
metadata,
credentials,
wait_for_ready,
request_iterator,
request_serializer,
response_deserializer,
)
)
super().__init__(interceptors_task)
# pylint: disable=too-many-arguments
async def _invoke(
self,
interceptors: Sequence[StreamStreamClientInterceptor],
method: bytes,
timeout: Optional[float],
metadata: Optional[Metadata],
credentials: Optional[grpc.CallCredentials],
wait_for_ready: Optional[bool],
request_iterator: RequestIterableType,
request_serializer: SerializingFunction,
response_deserializer: DeserializingFunction,
) -> StreamStreamCall:
"""Run the RPC call wrapped in interceptors"""
async def _run_interceptor(
interceptors: List[StreamStreamClientInterceptor],
client_call_details: ClientCallDetails,
request_iterator: RequestIterableType,
) -> _base_call.StreamStreamCall:
if interceptors:
continuation = functools.partial(
_run_interceptor, interceptors[1:]
)
call_or_response_iterator = await interceptors[
0
].intercept_stream_stream(
continuation, client_call_details, request_iterator
)
if isinstance(
call_or_response_iterator, _base_call.StreamStreamCall
):
self._last_returned_call_from_interceptors = (
call_or_response_iterator
)
else:
self._last_returned_call_from_interceptors = (
StreamStreamCallResponseIterator(
self._last_returned_call_from_interceptors,
call_or_response_iterator,
)
)
return self._last_returned_call_from_interceptors
else:
self._last_returned_call_from_interceptors = StreamStreamCall(
request_iterator,
_timeout_to_deadline(client_call_details.timeout),
client_call_details.metadata,
client_call_details.credentials,
client_call_details.wait_for_ready,
self._channel,
client_call_details.method,
request_serializer,
response_deserializer,
self._loop,
)
return self._last_returned_call_from_interceptors
client_call_details = ClientCallDetails(
method, timeout, metadata, credentials, wait_for_ready
)
return await _run_interceptor(
list(interceptors), client_call_details, request_iterator
)
def time_remaining(self) -> Optional[float]:
raise NotImplementedError()
class UnaryUnaryCallResponse(_base_call.UnaryUnaryCall):
"""Final UnaryUnaryCall class finished with a response."""
_response: ResponseType
def __init__(self, response: ResponseType) -> None:
self._response = response
def cancel(self) -> bool:
return False
def cancelled(self) -> bool:
return False
def done(self) -> bool:
return True
def add_done_callback(self, unused_callback) -> None:
raise NotImplementedError()
def time_remaining(self) -> Optional[float]:
raise NotImplementedError()
async def initial_metadata(self) -> Optional[Metadata]:
return None
async def trailing_metadata(self) -> Optional[Metadata]:
return None
async def code(self) -> grpc.StatusCode:
return grpc.StatusCode.OK
async def details(self) -> str:
return ""
async def debug_error_string(self) -> Optional[str]:
return None
def __await__(self):
if False: # pylint: disable=using-constant-test
# This code path is never used, but a yield statement is needed
# for telling the interpreter that __await__ is a generator.
yield None
return self._response
async def wait_for_connection(self) -> None:
pass
class _StreamCallResponseIterator:
_call: Union[_base_call.UnaryStreamCall, _base_call.StreamStreamCall]
_response_iterator: AsyncIterable[ResponseType]
def __init__(
self,
call: Union[_base_call.UnaryStreamCall, _base_call.StreamStreamCall],
response_iterator: AsyncIterable[ResponseType],
) -> None:
self._response_iterator = response_iterator
self._call = call
def cancel(self) -> bool:
return self._call.cancel()
def cancelled(self) -> bool:
return self._call.cancelled()
def done(self) -> bool:
return self._call.done()
def add_done_callback(self, callback) -> None:
self._call.add_done_callback(callback)
def time_remaining(self) -> Optional[float]:
return self._call.time_remaining()
async def initial_metadata(self) -> Optional[Metadata]:
return await self._call.initial_metadata()
async def trailing_metadata(self) -> Optional[Metadata]:
return await self._call.trailing_metadata()
async def code(self) -> grpc.StatusCode:
return await self._call.code()
async def details(self) -> str:
return await self._call.details()
async def debug_error_string(self) -> Optional[str]:
return await self._call.debug_error_string()
def __aiter__(self):
return self._response_iterator.__aiter__()
async def wait_for_connection(self) -> None:
return await self._call.wait_for_connection()
class UnaryStreamCallResponseIterator(
_StreamCallResponseIterator, _base_call.UnaryStreamCall
):
"""UnaryStreamCall class wich uses an alternative response iterator."""
async def read(self) -> ResponseType:
# Behind the scenes everyting goes through the
# async iterator. So this path should not be reached.
raise NotImplementedError()
class StreamStreamCallResponseIterator(
_StreamCallResponseIterator, _base_call.StreamStreamCall
):
"""StreamStreamCall class wich uses an alternative response iterator."""
async def read(self) -> ResponseType:
# Behind the scenes everyting goes through the
# async iterator. So this path should not be reached.
raise NotImplementedError()
async def write(self, request: RequestType) -> None:
# Behind the scenes everyting goes through the
# async iterator provided by the InterceptedStreamStreamCall.
# So this path should not be reached.
raise NotImplementedError()
async def done_writing(self) -> None:
# Behind the scenes everyting goes through the
# async iterator provided by the InterceptedStreamStreamCall.
# So this path should not be reached.
raise NotImplementedError()
@property
def _done_writing_flag(self) -> bool:
return self._call._done_writing_flag