From 7d5c3dcd969161322deed6c43f8a6a3cb92c3369 Mon Sep 17 00:00:00 2001 From: Micah Anderson Date: Tue, 11 Nov 2014 11:53:55 -0500 Subject: upgrade to 14.4.1 --- zmq/green/core.py | 287 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 287 insertions(+) create mode 100644 zmq/green/core.py (limited to 'zmq/green/core.py') diff --git a/zmq/green/core.py b/zmq/green/core.py new file mode 100644 index 0000000..9fc73e3 --- /dev/null +++ b/zmq/green/core.py @@ -0,0 +1,287 @@ +#----------------------------------------------------------------------------- +# Copyright (C) 2011-2012 Travis Cline +# +# This file is part of pyzmq +# It is adapted from upstream project zeromq_gevent under the New BSD License +# +# Distributed under the terms of the New BSD License. The full license is in +# the file COPYING.BSD, distributed as part of this software. +#----------------------------------------------------------------------------- + +"""This module wraps the :class:`Socket` and :class:`Context` found in :mod:`pyzmq ` to be non blocking +""" + +from __future__ import print_function + +import sys +import time +import warnings + +import zmq + +from zmq import Context as _original_Context +from zmq import Socket as _original_Socket +from .poll import _Poller + +import gevent +from gevent.event import AsyncResult +from gevent.hub import get_hub + +if hasattr(zmq, 'RCVTIMEO'): + TIMEOS = (zmq.RCVTIMEO, zmq.SNDTIMEO) +else: + TIMEOS = () + +def _stop(evt): + """simple wrapper for stopping an Event, allowing for method rename in gevent 1.0""" + try: + evt.stop() + except AttributeError as e: + # gevent<1.0 compat + evt.cancel() + +class _Socket(_original_Socket): + """Green version of :class:`zmq.Socket` + + The following methods are overridden: + + * send + * recv + + To ensure that the ``zmq.NOBLOCK`` flag is set and that sending or receiving + is deferred to the hub if a ``zmq.EAGAIN`` (retry) error is raised. + + The `__state_changed` method is triggered when the zmq.FD for the socket is + marked as readable and triggers the necessary read and write events (which + are waited for in the recv and send methods). + + Some double underscore prefixes are used to minimize pollution of + :class:`zmq.Socket`'s namespace. + """ + __in_send_multipart = False + __in_recv_multipart = False + __writable = None + __readable = None + _state_event = None + _gevent_bug_timeout = 11.6 # timeout for not trusting gevent + _debug_gevent = False # turn on if you think gevent is missing events + _poller_class = _Poller + + def __init__(self, context, socket_type): + _original_Socket.__init__(self, context, socket_type) + self.__in_send_multipart = False + self.__in_recv_multipart = False + self.__setup_events() + + + def __del__(self): + self.close() + + def close(self, linger=None): + super(_Socket, self).close(linger) + self.__cleanup_events() + + def __cleanup_events(self): + # close the _state_event event, keeps the number of active file descriptors down + if getattr(self, '_state_event', None): + _stop(self._state_event) + self._state_event = None + # if the socket has entered a close state resume any waiting greenlets + self.__writable.set() + self.__readable.set() + + def __setup_events(self): + self.__readable = AsyncResult() + self.__writable = AsyncResult() + self.__readable.set() + self.__writable.set() + + try: + self._state_event = get_hub().loop.io(self.getsockopt(zmq.FD), 1) # read state watcher + self._state_event.start(self.__state_changed) + except AttributeError: + # for gevent<1.0 compatibility + from gevent.core import read_event + self._state_event = read_event(self.getsockopt(zmq.FD), self.__state_changed, persist=True) + + def __state_changed(self, event=None, _evtype=None): + if self.closed: + self.__cleanup_events() + return + try: + # avoid triggering __state_changed from inside __state_changed + events = super(_Socket, self).getsockopt(zmq.EVENTS) + except zmq.ZMQError as exc: + self.__writable.set_exception(exc) + self.__readable.set_exception(exc) + else: + if events & zmq.POLLOUT: + self.__writable.set() + if events & zmq.POLLIN: + self.__readable.set() + + def _wait_write(self): + assert self.__writable.ready(), "Only one greenlet can be waiting on this event" + self.__writable = AsyncResult() + # timeout is because libzmq cannot be trusted to properly signal a new send event: + # this is effectively a maximum poll interval of 1s + tic = time.time() + dt = self._gevent_bug_timeout + if dt: + timeout = gevent.Timeout(seconds=dt) + else: + timeout = None + try: + if timeout: + timeout.start() + self.__writable.get(block=True) + except gevent.Timeout as t: + if t is not timeout: + raise + toc = time.time() + # gevent bug: get can raise timeout even on clean return + # don't display zmq bug warning for gevent bug (this is getting ridiculous) + if self._debug_gevent and timeout and toc-tic > dt and \ + self.getsockopt(zmq.EVENTS) & zmq.POLLOUT: + print("BUG: gevent may have missed a libzmq send event on %i!" % self.FD, file=sys.stderr) + finally: + if timeout: + timeout.cancel() + self.__writable.set() + + def _wait_read(self): + assert self.__readable.ready(), "Only one greenlet can be waiting on this event" + self.__readable = AsyncResult() + # timeout is because libzmq cannot always be trusted to play nice with libevent. + # I can only confirm that this actually happens for send, but lets be symmetrical + # with our dirty hacks. + # this is effectively a maximum poll interval of 1s + tic = time.time() + dt = self._gevent_bug_timeout + if dt: + timeout = gevent.Timeout(seconds=dt) + else: + timeout = None + try: + if timeout: + timeout.start() + self.__readable.get(block=True) + except gevent.Timeout as t: + if t is not timeout: + raise + toc = time.time() + # gevent bug: get can raise timeout even on clean return + # don't display zmq bug warning for gevent bug (this is getting ridiculous) + if self._debug_gevent and timeout and toc-tic > dt and \ + self.getsockopt(zmq.EVENTS) & zmq.POLLIN: + print("BUG: gevent may have missed a libzmq recv event on %i!" % self.FD, file=sys.stderr) + finally: + if timeout: + timeout.cancel() + self.__readable.set() + + def send(self, data, flags=0, copy=True, track=False): + """send, which will only block current greenlet + + state_changed always fires exactly once (success or fail) at the + end of this method. + """ + + # if we're given the NOBLOCK flag act as normal and let the EAGAIN get raised + if flags & zmq.NOBLOCK: + try: + msg = super(_Socket, self).send(data, flags, copy, track) + finally: + if not self.__in_send_multipart: + self.__state_changed() + return msg + # ensure the zmq.NOBLOCK flag is part of flags + flags |= zmq.NOBLOCK + while True: # Attempt to complete this operation indefinitely, blocking the current greenlet + try: + # attempt the actual call + msg = super(_Socket, self).send(data, flags, copy, track) + except zmq.ZMQError as e: + # if the raised ZMQError is not EAGAIN, reraise + if e.errno != zmq.EAGAIN: + if not self.__in_send_multipart: + self.__state_changed() + raise + else: + if not self.__in_send_multipart: + self.__state_changed() + return msg + # defer to the event loop until we're notified the socket is writable + self._wait_write() + + def recv(self, flags=0, copy=True, track=False): + """recv, which will only block current greenlet + + state_changed always fires exactly once (success or fail) at the + end of this method. + """ + if flags & zmq.NOBLOCK: + try: + msg = super(_Socket, self).recv(flags, copy, track) + finally: + if not self.__in_recv_multipart: + self.__state_changed() + return msg + + flags |= zmq.NOBLOCK + while True: + try: + msg = super(_Socket, self).recv(flags, copy, track) + except zmq.ZMQError as e: + if e.errno != zmq.EAGAIN: + if not self.__in_recv_multipart: + self.__state_changed() + raise + else: + if not self.__in_recv_multipart: + self.__state_changed() + return msg + self._wait_read() + + def send_multipart(self, *args, **kwargs): + """wrap send_multipart to prevent state_changed on each partial send""" + self.__in_send_multipart = True + try: + msg = super(_Socket, self).send_multipart(*args, **kwargs) + finally: + self.__in_send_multipart = False + self.__state_changed() + return msg + + def recv_multipart(self, *args, **kwargs): + """wrap recv_multipart to prevent state_changed on each partial recv""" + self.__in_recv_multipart = True + try: + msg = super(_Socket, self).recv_multipart(*args, **kwargs) + finally: + self.__in_recv_multipart = False + self.__state_changed() + return msg + + def get(self, opt): + """trigger state_changed on getsockopt(EVENTS)""" + if opt in TIMEOS: + warnings.warn("TIMEO socket options have no effect in zmq.green", UserWarning) + optval = super(_Socket, self).get(opt) + if opt == zmq.EVENTS: + self.__state_changed() + return optval + + def set(self, opt, val): + """set socket option""" + if opt in TIMEOS: + warnings.warn("TIMEO socket options have no effect in zmq.green", UserWarning) + return super(_Socket, self).set(opt, val) + + +class _Context(_original_Context): + """Replacement for :class:`zmq.Context` + + Ensures that the greened Socket above is used in calls to `socket`. + """ + _socket_class = _Socket -- cgit v1.2.3