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authorcyfraeviolae <cyfraeviolae>2024-04-03 03:10:44 -0400
committercyfraeviolae <cyfraeviolae>2024-04-03 03:10:44 -0400
commit6d7ba58f880be618ade07f8ea080fe8c4bf8a896 (patch)
treeb1c931051ffcebd2bd9d61d98d6233ffa289bbce /venv/lib/python3.11/site-packages/anyio/streams/memory.py
parent4f884c9abc32990b4061a1bb6997b4b37e58ea0b (diff)
venv
Diffstat (limited to 'venv/lib/python3.11/site-packages/anyio/streams/memory.py')
-rw-r--r--venv/lib/python3.11/site-packages/anyio/streams/memory.py283
1 files changed, 283 insertions, 0 deletions
diff --git a/venv/lib/python3.11/site-packages/anyio/streams/memory.py b/venv/lib/python3.11/site-packages/anyio/streams/memory.py
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+++ b/venv/lib/python3.11/site-packages/anyio/streams/memory.py
@@ -0,0 +1,283 @@
+from __future__ import annotations
+
+from collections import OrderedDict, deque
+from dataclasses import dataclass, field
+from types import TracebackType
+from typing import Generic, NamedTuple, TypeVar
+
+from .. import (
+ BrokenResourceError,
+ ClosedResourceError,
+ EndOfStream,
+ WouldBlock,
+)
+from ..abc import Event, ObjectReceiveStream, ObjectSendStream
+from ..lowlevel import checkpoint
+
+T_Item = TypeVar("T_Item")
+T_co = TypeVar("T_co", covariant=True)
+T_contra = TypeVar("T_contra", contravariant=True)
+
+
+class MemoryObjectStreamStatistics(NamedTuple):
+ current_buffer_used: int #: number of items stored in the buffer
+ #: maximum number of items that can be stored on this stream (or :data:`math.inf`)
+ max_buffer_size: float
+ open_send_streams: int #: number of unclosed clones of the send stream
+ open_receive_streams: int #: number of unclosed clones of the receive stream
+ #: number of tasks blocked on :meth:`MemoryObjectSendStream.send`
+ tasks_waiting_send: int
+ #: number of tasks blocked on :meth:`MemoryObjectReceiveStream.receive`
+ tasks_waiting_receive: int
+
+
+@dataclass(eq=False)
+class MemoryObjectStreamState(Generic[T_Item]):
+ max_buffer_size: float = field()
+ buffer: deque[T_Item] = field(init=False, default_factory=deque)
+ open_send_channels: int = field(init=False, default=0)
+ open_receive_channels: int = field(init=False, default=0)
+ waiting_receivers: OrderedDict[Event, list[T_Item]] = field(
+ init=False, default_factory=OrderedDict
+ )
+ waiting_senders: OrderedDict[Event, T_Item] = field(
+ init=False, default_factory=OrderedDict
+ )
+
+ def statistics(self) -> MemoryObjectStreamStatistics:
+ return MemoryObjectStreamStatistics(
+ len(self.buffer),
+ self.max_buffer_size,
+ self.open_send_channels,
+ self.open_receive_channels,
+ len(self.waiting_senders),
+ len(self.waiting_receivers),
+ )
+
+
+@dataclass(eq=False)
+class MemoryObjectReceiveStream(Generic[T_co], ObjectReceiveStream[T_co]):
+ _state: MemoryObjectStreamState[T_co]
+ _closed: bool = field(init=False, default=False)
+
+ def __post_init__(self) -> None:
+ self._state.open_receive_channels += 1
+
+ def receive_nowait(self) -> T_co:
+ """
+ Receive the next item if it can be done without waiting.
+
+ :return: the received item
+ :raises ~anyio.ClosedResourceError: if this send stream has been closed
+ :raises ~anyio.EndOfStream: if the buffer is empty and this stream has been
+ closed from the sending end
+ :raises ~anyio.WouldBlock: if there are no items in the buffer and no tasks
+ waiting to send
+
+ """
+ if self._closed:
+ raise ClosedResourceError
+
+ if self._state.waiting_senders:
+ # Get the item from the next sender
+ send_event, item = self._state.waiting_senders.popitem(last=False)
+ self._state.buffer.append(item)
+ send_event.set()
+
+ if self._state.buffer:
+ return self._state.buffer.popleft()
+ elif not self._state.open_send_channels:
+ raise EndOfStream
+
+ raise WouldBlock
+
+ async def receive(self) -> T_co:
+ await checkpoint()
+ try:
+ return self.receive_nowait()
+ except WouldBlock:
+ # Add ourselves in the queue
+ receive_event = Event()
+ container: list[T_co] = []
+ self._state.waiting_receivers[receive_event] = container
+
+ try:
+ await receive_event.wait()
+ finally:
+ self._state.waiting_receivers.pop(receive_event, None)
+
+ if container:
+ return container[0]
+ else:
+ raise EndOfStream
+
+ def clone(self) -> MemoryObjectReceiveStream[T_co]:
+ """
+ Create a clone of this receive stream.
+
+ Each clone can be closed separately. Only when all clones have been closed will
+ the receiving end of the memory stream be considered closed by the sending ends.
+
+ :return: the cloned stream
+
+ """
+ if self._closed:
+ raise ClosedResourceError
+
+ return MemoryObjectReceiveStream(_state=self._state)
+
+ def close(self) -> None:
+ """
+ Close the stream.
+
+ This works the exact same way as :meth:`aclose`, but is provided as a special
+ case for the benefit of synchronous callbacks.
+
+ """
+ if not self._closed:
+ self._closed = True
+ self._state.open_receive_channels -= 1
+ if self._state.open_receive_channels == 0:
+ send_events = list(self._state.waiting_senders.keys())
+ for event in send_events:
+ event.set()
+
+ async def aclose(self) -> None:
+ self.close()
+
+ def statistics(self) -> MemoryObjectStreamStatistics:
+ """
+ Return statistics about the current state of this stream.
+
+ .. versionadded:: 3.0
+ """
+ return self._state.statistics()
+
+ def __enter__(self) -> MemoryObjectReceiveStream[T_co]:
+ return self
+
+ def __exit__(
+ self,
+ exc_type: type[BaseException] | None,
+ exc_val: BaseException | None,
+ exc_tb: TracebackType | None,
+ ) -> None:
+ self.close()
+
+
+@dataclass(eq=False)
+class MemoryObjectSendStream(Generic[T_contra], ObjectSendStream[T_contra]):
+ _state: MemoryObjectStreamState[T_contra]
+ _closed: bool = field(init=False, default=False)
+
+ def __post_init__(self) -> None:
+ self._state.open_send_channels += 1
+
+ def send_nowait(self, item: T_contra) -> None:
+ """
+ Send an item immediately if it can be done without waiting.
+
+ :param item: the item to send
+ :raises ~anyio.ClosedResourceError: if this send stream has been closed
+ :raises ~anyio.BrokenResourceError: if the stream has been closed from the
+ receiving end
+ :raises ~anyio.WouldBlock: if the buffer is full and there are no tasks waiting
+ to receive
+
+ """
+ if self._closed:
+ raise ClosedResourceError
+ if not self._state.open_receive_channels:
+ raise BrokenResourceError
+
+ if self._state.waiting_receivers:
+ receive_event, container = self._state.waiting_receivers.popitem(last=False)
+ container.append(item)
+ receive_event.set()
+ elif len(self._state.buffer) < self._state.max_buffer_size:
+ self._state.buffer.append(item)
+ else:
+ raise WouldBlock
+
+ async def send(self, item: T_contra) -> None:
+ """
+ Send an item to the stream.
+
+ If the buffer is full, this method blocks until there is again room in the
+ buffer or the item can be sent directly to a receiver.
+
+ :param item: the item to send
+ :raises ~anyio.ClosedResourceError: if this send stream has been closed
+ :raises ~anyio.BrokenResourceError: if the stream has been closed from the
+ receiving end
+
+ """
+ await checkpoint()
+ try:
+ self.send_nowait(item)
+ except WouldBlock:
+ # Wait until there's someone on the receiving end
+ send_event = Event()
+ self._state.waiting_senders[send_event] = item
+ try:
+ await send_event.wait()
+ except BaseException:
+ self._state.waiting_senders.pop(send_event, None)
+ raise
+
+ if self._state.waiting_senders.pop(send_event, None):
+ raise BrokenResourceError from None
+
+ def clone(self) -> MemoryObjectSendStream[T_contra]:
+ """
+ Create a clone of this send stream.
+
+ Each clone can be closed separately. Only when all clones have been closed will
+ the sending end of the memory stream be considered closed by the receiving ends.
+
+ :return: the cloned stream
+
+ """
+ if self._closed:
+ raise ClosedResourceError
+
+ return MemoryObjectSendStream(_state=self._state)
+
+ def close(self) -> None:
+ """
+ Close the stream.
+
+ This works the exact same way as :meth:`aclose`, but is provided as a special
+ case for the benefit of synchronous callbacks.
+
+ """
+ if not self._closed:
+ self._closed = True
+ self._state.open_send_channels -= 1
+ if self._state.open_send_channels == 0:
+ receive_events = list(self._state.waiting_receivers.keys())
+ self._state.waiting_receivers.clear()
+ for event in receive_events:
+ event.set()
+
+ async def aclose(self) -> None:
+ self.close()
+
+ def statistics(self) -> MemoryObjectStreamStatistics:
+ """
+ Return statistics about the current state of this stream.
+
+ .. versionadded:: 3.0
+ """
+ return self._state.statistics()
+
+ def __enter__(self) -> MemoryObjectSendStream[T_contra]:
+ return self
+
+ def __exit__(
+ self,
+ exc_type: type[BaseException] | None,
+ exc_val: BaseException | None,
+ exc_tb: TracebackType | None,
+ ) -> None:
+ self.close()