AIM-PIbd-32-Kurbanova-A-A/aimenv/Lib/site-packages/zmq/_future.py

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2024-10-02 22:15:59 +04:00
"""Future-returning APIs for coroutines."""
# Copyright (c) PyZMQ Developers.
# Distributed under the terms of the Modified BSD License.
from __future__ import annotations
import warnings
from asyncio import Future
from collections import deque
from functools import partial
from itertools import chain
from typing import Any, Awaitable, Callable, NamedTuple, TypeVar, cast, overload
import zmq as _zmq
from zmq import EVENTS, POLLIN, POLLOUT
from zmq._typing import Literal
class _FutureEvent(NamedTuple):
future: Future
kind: str
kwargs: dict
msg: Any
timer: Any
# These are incomplete classes and need a Mixin for compatibility with an eventloop
# defining the following attributes:
#
# _Future
# _READ
# _WRITE
# _default_loop()
class _Async:
"""Mixin for common async logic"""
_current_loop: Any = None
_Future: type[Future]
def _get_loop(self) -> Any:
"""Get event loop
Notice if event loop has changed,
and register init_io_state on activation of a new event loop
"""
if self._current_loop is None:
self._current_loop = self._default_loop()
self._init_io_state(self._current_loop)
return self._current_loop
current_loop = self._default_loop()
if current_loop is not self._current_loop:
# warn? This means a socket is being used in multiple loops!
self._current_loop = current_loop
self._init_io_state(current_loop)
return current_loop
def _default_loop(self) -> Any:
raise NotImplementedError("Must be implemented in a subclass")
def _init_io_state(self, loop=None) -> None:
pass
class _AsyncPoller(_Async, _zmq.Poller):
"""Poller that returns a Future on poll, instead of blocking."""
_socket_class: type[_AsyncSocket]
_READ: int
_WRITE: int
raw_sockets: list[Any]
def _watch_raw_socket(self, loop: Any, socket: Any, evt: int, f: Callable) -> None:
"""Schedule callback for a raw socket"""
raise NotImplementedError()
def _unwatch_raw_sockets(self, loop: Any, *sockets: Any) -> None:
"""Unschedule callback for a raw socket"""
raise NotImplementedError()
def poll(self, timeout=-1) -> Awaitable[list[tuple[Any, int]]]: # type: ignore
"""Return a Future for a poll event"""
future = self._Future()
if timeout == 0:
try:
result = super().poll(0)
except Exception as e:
future.set_exception(e)
else:
future.set_result(result)
return future
loop = self._get_loop()
# register Future to be called as soon as any event is available on any socket
watcher = self._Future()
# watch raw sockets:
raw_sockets: list[Any] = []
def wake_raw(*args):
if not watcher.done():
watcher.set_result(None)
watcher.add_done_callback(
lambda f: self._unwatch_raw_sockets(loop, *raw_sockets)
)
wrapped_sockets: list[_AsyncSocket] = []
def _clear_wrapper_io(f):
for s in wrapped_sockets:
s._clear_io_state()
for socket, mask in self.sockets:
if isinstance(socket, _zmq.Socket):
if not isinstance(socket, self._socket_class):
# it's a blocking zmq.Socket, wrap it in async
socket = self._socket_class.from_socket(socket)
wrapped_sockets.append(socket)
if mask & _zmq.POLLIN:
socket._add_recv_event('poll', future=watcher)
if mask & _zmq.POLLOUT:
socket._add_send_event('poll', future=watcher)
else:
raw_sockets.append(socket)
evt = 0
if mask & _zmq.POLLIN:
evt |= self._READ
if mask & _zmq.POLLOUT:
evt |= self._WRITE
self._watch_raw_socket(loop, socket, evt, wake_raw)
def on_poll_ready(f):
if future.done():
return
if watcher.cancelled():
try:
future.cancel()
except RuntimeError:
# RuntimeError may be called during teardown
pass
return
if watcher.exception():
future.set_exception(watcher.exception())
else:
try:
result = super(_AsyncPoller, self).poll(0)
except Exception as e:
future.set_exception(e)
else:
future.set_result(result)
watcher.add_done_callback(on_poll_ready)
if wrapped_sockets:
watcher.add_done_callback(_clear_wrapper_io)
if timeout is not None and timeout > 0:
# schedule cancel to fire on poll timeout, if any
def trigger_timeout():
if not watcher.done():
watcher.set_result(None)
timeout_handle = loop.call_later(1e-3 * timeout, trigger_timeout)
def cancel_timeout(f):
if hasattr(timeout_handle, 'cancel'):
timeout_handle.cancel()
else:
loop.remove_timeout(timeout_handle)
future.add_done_callback(cancel_timeout)
def cancel_watcher(f):
if not watcher.done():
watcher.cancel()
future.add_done_callback(cancel_watcher)
return future
class _NoTimer:
@staticmethod
def cancel():
pass
T = TypeVar("T", bound="_AsyncSocket")
class _AsyncSocket(_Async, _zmq.Socket[Future]):
# Warning : these class variables are only here to allow to call super().__setattr__.
# They be overridden at instance initialization and not shared in the whole class
_recv_futures = None
_send_futures = None
_state = 0
_shadow_sock: _zmq.Socket
_poller_class = _AsyncPoller
_fd = None
def __init__(
self,
context=None,
socket_type=-1,
io_loop=None,
_from_socket: _zmq.Socket | None = None,
**kwargs,
) -> None:
if isinstance(context, _zmq.Socket):
context, _from_socket = (None, context)
if _from_socket is not None:
super().__init__(shadow=_from_socket.underlying) # type: ignore
self._shadow_sock = _from_socket
else:
super().__init__(context, socket_type, **kwargs) # type: ignore
self._shadow_sock = _zmq.Socket.shadow(self.underlying)
if io_loop is not None:
warnings.warn(
f"{self.__class__.__name__}(io_loop) argument is deprecated in pyzmq 22.2."
" The currently active loop will always be used.",
DeprecationWarning,
stacklevel=3,
)
self._recv_futures = deque()
self._send_futures = deque()
self._state = 0
self._fd = self._shadow_sock.FD
@classmethod
def from_socket(cls: type[T], socket: _zmq.Socket, io_loop: Any = None) -> T:
"""Create an async socket from an existing Socket"""
return cls(_from_socket=socket, io_loop=io_loop)
def close(self, linger: int | None = None) -> None:
if not self.closed and self._fd is not None:
event_list: list[_FutureEvent] = list(
chain(self._recv_futures or [], self._send_futures or [])
)
for event in event_list:
if not event.future.done():
try:
event.future.cancel()
except RuntimeError:
# RuntimeError may be called during teardown
pass
self._clear_io_state()
super().close(linger=linger)
close.__doc__ = _zmq.Socket.close.__doc__
def get(self, key):
result = super().get(key)
if key == EVENTS:
self._schedule_remaining_events(result)
return result
get.__doc__ = _zmq.Socket.get.__doc__
@overload # type: ignore
def recv_multipart(
self, flags: int = 0, *, track: bool = False
) -> Awaitable[list[bytes]]: ...
@overload
def recv_multipart(
self, flags: int = 0, *, copy: Literal[True], track: bool = False
) -> Awaitable[list[bytes]]: ...
@overload
def recv_multipart(
self, flags: int = 0, *, copy: Literal[False], track: bool = False
) -> Awaitable[list[_zmq.Frame]]: # type: ignore
...
@overload
def recv_multipart(
self, flags: int = 0, copy: bool = True, track: bool = False
) -> Awaitable[list[bytes] | list[_zmq.Frame]]: ...
def recv_multipart(
self, flags: int = 0, copy: bool = True, track: bool = False
) -> Awaitable[list[bytes] | list[_zmq.Frame]]:
"""Receive a complete multipart zmq message.
Returns a Future whose result will be a multipart message.
"""
return self._add_recv_event(
'recv_multipart', dict(flags=flags, copy=copy, track=track)
)
@overload # type: ignore
def recv(self, flags: int = 0, *, track: bool = False) -> Awaitable[bytes]: ...
@overload
def recv(
self, flags: int = 0, *, copy: Literal[True], track: bool = False
) -> Awaitable[bytes]: ...
@overload
def recv(
self, flags: int = 0, *, copy: Literal[False], track: bool = False
) -> Awaitable[_zmq.Frame]: ...
def recv( # type: ignore
self, flags: int = 0, copy: bool = True, track: bool = False
) -> Awaitable[bytes | _zmq.Frame]:
"""Receive a single zmq frame.
Returns a Future, whose result will be the received frame.
Recommend using recv_multipart instead.
"""
return self._add_recv_event('recv', dict(flags=flags, copy=copy, track=track))
def send_multipart( # type: ignore
self, msg_parts: Any, flags: int = 0, copy: bool = True, track=False, **kwargs
) -> Awaitable[_zmq.MessageTracker | None]:
"""Send a complete multipart zmq message.
Returns a Future that resolves when sending is complete.
"""
kwargs['flags'] = flags
kwargs['copy'] = copy
kwargs['track'] = track
return self._add_send_event('send_multipart', msg=msg_parts, kwargs=kwargs)
def send( # type: ignore
self,
data: Any,
flags: int = 0,
copy: bool = True,
track: bool = False,
**kwargs: Any,
) -> Awaitable[_zmq.MessageTracker | None]:
"""Send a single zmq frame.
Returns a Future that resolves when sending is complete.
Recommend using send_multipart instead.
"""
kwargs['flags'] = flags
kwargs['copy'] = copy
kwargs['track'] = track
kwargs.update(dict(flags=flags, copy=copy, track=track))
return self._add_send_event('send', msg=data, kwargs=kwargs)
def _deserialize(self, recvd, load):
"""Deserialize with Futures"""
f = self._Future()
def _chain(_):
"""Chain result through serialization to recvd"""
if f.done():
# chained future may be cancelled, which means nobody is going to get this result
# if it's an error, that's no big deal (probably zmq.Again),
# but if it's a successful recv, this is a dropped message!
if not recvd.cancelled() and recvd.exception() is None:
warnings.warn(
# is there a useful stacklevel?
# ideally, it would point to where `f.cancel()` was called
f"Future {f} completed while awaiting {recvd}. A message has been dropped!",
RuntimeWarning,
)
return
if recvd.exception():
f.set_exception(recvd.exception())
else:
buf = recvd.result()
try:
loaded = load(buf)
except Exception as e:
f.set_exception(e)
else:
f.set_result(loaded)
recvd.add_done_callback(_chain)
def _chain_cancel(_):
"""Chain cancellation from f to recvd"""
if recvd.done():
return
if f.cancelled():
recvd.cancel()
f.add_done_callback(_chain_cancel)
return f
def poll(self, timeout=None, flags=_zmq.POLLIN) -> Awaitable[int]: # type: ignore
"""poll the socket for events
returns a Future for the poll results.
"""
if self.closed:
raise _zmq.ZMQError(_zmq.ENOTSUP)
p = self._poller_class()
p.register(self, flags)
poll_future = cast(Future, p.poll(timeout))
future = self._Future()
def unwrap_result(f):
if future.done():
return
if poll_future.cancelled():
try:
future.cancel()
except RuntimeError:
# RuntimeError may be called during teardown
pass
return
if f.exception():
future.set_exception(poll_future.exception())
else:
evts = dict(poll_future.result())
future.set_result(evts.get(self, 0))
if poll_future.done():
# hook up result if already done
unwrap_result(poll_future)
else:
poll_future.add_done_callback(unwrap_result)
def cancel_poll(future):
"""Cancel underlying poll if request has been cancelled"""
if not poll_future.done():
try:
poll_future.cancel()
except RuntimeError:
# RuntimeError may be called during teardown
pass
future.add_done_callback(cancel_poll)
return future
# overrides only necessary for updated types
def recv_string(self, *args, **kwargs) -> Awaitable[str]: # type: ignore
return super().recv_string(*args, **kwargs) # type: ignore
def send_string( # type: ignore
self, s: str, flags: int = 0, encoding: str = 'utf-8'
) -> Awaitable[None]:
return super().send_string(s, flags=flags, encoding=encoding) # type: ignore
def _add_timeout(self, future, timeout):
"""Add a timeout for a send or recv Future"""
def future_timeout():
if future.done():
# future already resolved, do nothing
return
# raise EAGAIN
future.set_exception(_zmq.Again())
return self._call_later(timeout, future_timeout)
def _call_later(self, delay, callback):
"""Schedule a function to be called later
Override for different IOLoop implementations
Tornado and asyncio happen to both have ioloop.call_later
with the same signature.
"""
return self._get_loop().call_later(delay, callback)
@staticmethod
def _remove_finished_future(future, event_list, event=None):
"""Make sure that futures are removed from the event list when they resolve
Avoids delaying cleanup until the next send/recv event,
which may never come.
"""
# "future" instance is shared between sockets, but each socket has its own event list.
if not event_list:
return
# only unconsumed events (e.g. cancelled calls)
# will be present when this happens
try:
event_list.remove(event)
except ValueError:
# usually this will have been removed by being consumed
return
def _add_recv_event(self, kind, kwargs=None, future=None):
"""Add a recv event, returning the corresponding Future"""
f = future or self._Future()
if kind.startswith('recv') and kwargs.get('flags', 0) & _zmq.DONTWAIT:
# short-circuit non-blocking calls
recv = getattr(self._shadow_sock, kind)
try:
r = recv(**kwargs)
except Exception as e:
f.set_exception(e)
else:
f.set_result(r)
return f
timer = _NoTimer
if hasattr(_zmq, 'RCVTIMEO'):
timeout_ms = self._shadow_sock.rcvtimeo
if timeout_ms >= 0:
timer = self._add_timeout(f, timeout_ms * 1e-3)
# we add it to the list of futures before we add the timeout as the
# timeout will remove the future from recv_futures to avoid leaks
_future_event = _FutureEvent(f, kind, kwargs, msg=None, timer=timer)
self._recv_futures.append(_future_event)
if self._shadow_sock.get(EVENTS) & POLLIN:
# recv immediately, if we can
self._handle_recv()
if self._recv_futures and _future_event in self._recv_futures:
# Don't let the Future sit in _recv_events after it's done
# no need to register this if we've already been handled
# (i.e. immediately-resolved recv)
f.add_done_callback(
partial(
self._remove_finished_future,
event_list=self._recv_futures,
event=_future_event,
)
)
self._add_io_state(POLLIN)
return f
def _add_send_event(self, kind, msg=None, kwargs=None, future=None):
"""Add a send event, returning the corresponding Future"""
f = future or self._Future()
# attempt send with DONTWAIT if no futures are waiting
# short-circuit for sends that will resolve immediately
# only call if no send Futures are waiting
if kind in ('send', 'send_multipart') and not self._send_futures:
flags = kwargs.get('flags', 0)
nowait_kwargs = kwargs.copy()
nowait_kwargs['flags'] = flags | _zmq.DONTWAIT
# short-circuit non-blocking calls
send = getattr(self._shadow_sock, kind)
# track if the send resolved or not
# (EAGAIN if DONTWAIT is not set should proceed with)
finish_early = True
try:
r = send(msg, **nowait_kwargs)
except _zmq.Again as e:
if flags & _zmq.DONTWAIT:
f.set_exception(e)
else:
# EAGAIN raised and DONTWAIT not requested,
# proceed with async send
finish_early = False
except Exception as e:
f.set_exception(e)
else:
f.set_result(r)
if finish_early:
# short-circuit resolved, return finished Future
# schedule wake for recv if there are any receivers waiting
if self._recv_futures:
self._schedule_remaining_events()
return f
timer = _NoTimer
if hasattr(_zmq, 'SNDTIMEO'):
timeout_ms = self._shadow_sock.get(_zmq.SNDTIMEO)
if timeout_ms >= 0:
timer = self._add_timeout(f, timeout_ms * 1e-3)
# we add it to the list of futures before we add the timeout as the
# timeout will remove the future from recv_futures to avoid leaks
_future_event = _FutureEvent(f, kind, kwargs=kwargs, msg=msg, timer=timer)
self._send_futures.append(_future_event)
# Don't let the Future sit in _send_futures after it's done
f.add_done_callback(
partial(
self._remove_finished_future,
event_list=self._send_futures,
event=_future_event,
)
)
self._add_io_state(POLLOUT)
return f
def _handle_recv(self):
"""Handle recv events"""
if not self._shadow_sock.get(EVENTS) & POLLIN:
# event triggered, but state may have been changed between trigger and callback
return
f = None
while self._recv_futures:
f, kind, kwargs, _, timer = self._recv_futures.popleft()
# skip any cancelled futures
if f.done():
f = None
else:
break
if not self._recv_futures:
self._drop_io_state(POLLIN)
if f is None:
return
timer.cancel()
if kind == 'poll':
# on poll event, just signal ready, nothing else.
f.set_result(None)
return
elif kind == 'recv_multipart':
recv = self._shadow_sock.recv_multipart
elif kind == 'recv':
recv = self._shadow_sock.recv
else:
raise ValueError(f"Unhandled recv event type: {kind!r}")
kwargs['flags'] |= _zmq.DONTWAIT
try:
result = recv(**kwargs)
except Exception as e:
f.set_exception(e)
else:
f.set_result(result)
def _handle_send(self):
if not self._shadow_sock.get(EVENTS) & POLLOUT:
# event triggered, but state may have been changed between trigger and callback
return
f = None
while self._send_futures:
f, kind, kwargs, msg, timer = self._send_futures.popleft()
# skip any cancelled futures
if f.done():
f = None
else:
break
if not self._send_futures:
self._drop_io_state(POLLOUT)
if f is None:
return
timer.cancel()
if kind == 'poll':
# on poll event, just signal ready, nothing else.
f.set_result(None)
return
elif kind == 'send_multipart':
send = self._shadow_sock.send_multipart
elif kind == 'send':
send = self._shadow_sock.send
else:
raise ValueError(f"Unhandled send event type: {kind!r}")
kwargs['flags'] |= _zmq.DONTWAIT
try:
result = send(msg, **kwargs)
except Exception as e:
f.set_exception(e)
else:
f.set_result(result)
# event masking from ZMQStream
def _handle_events(self, fd=0, events=0):
"""Dispatch IO events to _handle_recv, etc."""
if self._shadow_sock.closed:
return
zmq_events = self._shadow_sock.get(EVENTS)
if zmq_events & _zmq.POLLIN:
self._handle_recv()
if zmq_events & _zmq.POLLOUT:
self._handle_send()
self._schedule_remaining_events()
def _schedule_remaining_events(self, events=None):
"""Schedule a call to handle_events next loop iteration
If there are still events to handle.
"""
# edge-triggered handling
# allow passing events in, in case this is triggered by retrieving events,
# so we don't have to retrieve it twice.
if self._state == 0:
# not watching for anything, nothing to schedule
return
if events is None:
events = self._shadow_sock.get(EVENTS)
if events & self._state:
self._call_later(0, self._handle_events)
def _add_io_state(self, state):
"""Add io_state to poller."""
if self._state != state:
state = self._state = self._state | state
self._update_handler(self._state)
def _drop_io_state(self, state):
"""Stop poller from watching an io_state."""
if self._state & state:
self._state = self._state & (~state)
self._update_handler(self._state)
def _update_handler(self, state):
"""Update IOLoop handler with state.
zmq FD is always read-only.
"""
# ensure loop is registered and init_io has been called
# if there are any events to watch for
if state:
self._get_loop()
self._schedule_remaining_events()
def _init_io_state(self, loop=None):
"""initialize the ioloop event handler"""
if loop is None:
loop = self._get_loop()
loop.add_handler(self._shadow_sock, self._handle_events, self._READ)
self._call_later(0, self._handle_events)
def _clear_io_state(self):
"""unregister the ioloop event handler
called once during close
"""
fd = self._shadow_sock
if self._shadow_sock.closed:
fd = self._fd
if self._current_loop is not None:
self._current_loop.remove_handler(fd)