/usr/lib/python3.4/asyncio/base_events.py is in libpython3.4-stdlib 3.4.3-1ubuntu1~14.04.7.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 | """Base implementation of event loop.
The event loop can be broken up into a multiplexer (the part
responsible for notifying us of I/O events) and the event loop proper,
which wraps a multiplexer with functionality for scheduling callbacks,
immediately or at a given time in the future.
Whenever a public API takes a callback, subsequent positional
arguments will be passed to the callback if/when it is called. This
avoids the proliferation of trivial lambdas implementing closures.
Keyword arguments for the callback are not supported; this is a
conscious design decision, leaving the door open for keyword arguments
to modify the meaning of the API call itself.
"""
import collections
import concurrent.futures
import heapq
import inspect
import logging
import os
import socket
import subprocess
import threading
import time
import traceback
import sys
import warnings
from . import coroutines
from . import events
from . import futures
from . import tasks
from .coroutines import coroutine
from .log import logger
__all__ = ['BaseEventLoop']
# Argument for default thread pool executor creation.
_MAX_WORKERS = 5
# Minimum number of _scheduled timer handles before cleanup of
# cancelled handles is performed.
_MIN_SCHEDULED_TIMER_HANDLES = 100
# Minimum fraction of _scheduled timer handles that are cancelled
# before cleanup of cancelled handles is performed.
_MIN_CANCELLED_TIMER_HANDLES_FRACTION = 0.5
def _format_handle(handle):
cb = handle._callback
if inspect.ismethod(cb) and isinstance(cb.__self__, tasks.Task):
# format the task
return repr(cb.__self__)
else:
return str(handle)
def _format_pipe(fd):
if fd == subprocess.PIPE:
return '<pipe>'
elif fd == subprocess.STDOUT:
return '<stdout>'
else:
return repr(fd)
class _StopError(BaseException):
"""Raised to stop the event loop."""
def _check_resolved_address(sock, address):
# Ensure that the address is already resolved to avoid the trap of hanging
# the entire event loop when the address requires doing a DNS lookup.
#
# getaddrinfo() is slow (around 10 us per call): this function should only
# be called in debug mode
family = sock.family
if family == socket.AF_INET:
host, port = address
elif family == socket.AF_INET6:
host, port = address[:2]
else:
return
# On Windows, socket.inet_pton() is only available since Python 3.4
if hasattr(socket, 'inet_pton'):
# getaddrinfo() is slow and has known issue: prefer inet_pton()
# if available
try:
socket.inet_pton(family, host)
except OSError as exc:
raise ValueError("address must be resolved (IP address), "
"got host %r: %s"
% (host, exc))
else:
# Use getaddrinfo(flags=AI_NUMERICHOST) to ensure that the address is
# already resolved.
type_mask = 0
if hasattr(socket, 'SOCK_NONBLOCK'):
type_mask |= socket.SOCK_NONBLOCK
if hasattr(socket, 'SOCK_CLOEXEC'):
type_mask |= socket.SOCK_CLOEXEC
try:
socket.getaddrinfo(host, port,
family=family,
type=(sock.type & ~type_mask),
proto=sock.proto,
flags=socket.AI_NUMERICHOST)
except socket.gaierror as err:
raise ValueError("address must be resolved (IP address), "
"got host %r: %s"
% (host, err))
def _raise_stop_error(*args):
raise _StopError
def _run_until_complete_cb(fut):
exc = fut._exception
if (isinstance(exc, BaseException)
and not isinstance(exc, Exception)):
# Issue #22429: run_forever() already finished, no need to
# stop it.
return
_raise_stop_error()
class Server(events.AbstractServer):
def __init__(self, loop, sockets):
self._loop = loop
self.sockets = sockets
self._active_count = 0
self._waiters = []
def __repr__(self):
return '<%s sockets=%r>' % (self.__class__.__name__, self.sockets)
def _attach(self):
assert self.sockets is not None
self._active_count += 1
def _detach(self):
assert self._active_count > 0
self._active_count -= 1
if self._active_count == 0 and self.sockets is None:
self._wakeup()
def close(self):
sockets = self.sockets
if sockets is None:
return
self.sockets = None
for sock in sockets:
self._loop._stop_serving(sock)
if self._active_count == 0:
self._wakeup()
def _wakeup(self):
waiters = self._waiters
self._waiters = None
for waiter in waiters:
if not waiter.done():
waiter.set_result(waiter)
@coroutine
def wait_closed(self):
if self.sockets is None or self._waiters is None:
return
waiter = futures.Future(loop=self._loop)
self._waiters.append(waiter)
yield from waiter
class BaseEventLoop(events.AbstractEventLoop):
def __init__(self):
self._timer_cancelled_count = 0
self._closed = False
self._ready = collections.deque()
self._scheduled = []
self._default_executor = None
self._internal_fds = 0
# Identifier of the thread running the event loop, or None if the
# event loop is not running
self._thread_id = None
self._clock_resolution = time.get_clock_info('monotonic').resolution
self._exception_handler = None
self._debug = (not sys.flags.ignore_environment
and bool(os.environ.get('PYTHONASYNCIODEBUG')))
# In debug mode, if the execution of a callback or a step of a task
# exceed this duration in seconds, the slow callback/task is logged.
self.slow_callback_duration = 0.1
self._current_handle = None
def __repr__(self):
return ('<%s running=%s closed=%s debug=%s>'
% (self.__class__.__name__, self.is_running(),
self.is_closed(), self.get_debug()))
def create_task(self, coro):
"""Schedule a coroutine object.
Return a task object.
"""
self._check_closed()
task = tasks.Task(coro, loop=self)
if task._source_traceback:
del task._source_traceback[-1]
return task
def _make_socket_transport(self, sock, protocol, waiter=None, *,
extra=None, server=None):
"""Create socket transport."""
raise NotImplementedError
def _make_ssl_transport(self, rawsock, protocol, sslcontext, waiter=None,
*, server_side=False, server_hostname=None,
extra=None, server=None):
"""Create SSL transport."""
raise NotImplementedError
def _make_datagram_transport(self, sock, protocol,
address=None, waiter=None, extra=None):
"""Create datagram transport."""
raise NotImplementedError
def _make_read_pipe_transport(self, pipe, protocol, waiter=None,
extra=None):
"""Create read pipe transport."""
raise NotImplementedError
def _make_write_pipe_transport(self, pipe, protocol, waiter=None,
extra=None):
"""Create write pipe transport."""
raise NotImplementedError
@coroutine
def _make_subprocess_transport(self, protocol, args, shell,
stdin, stdout, stderr, bufsize,
extra=None, **kwargs):
"""Create subprocess transport."""
raise NotImplementedError
def _write_to_self(self):
"""Write a byte to self-pipe, to wake up the event loop.
This may be called from a different thread.
The subclass is responsible for implementing the self-pipe.
"""
raise NotImplementedError
def _process_events(self, event_list):
"""Process selector events."""
raise NotImplementedError
def _check_closed(self):
if self._closed:
raise RuntimeError('Event loop is closed')
def run_forever(self):
"""Run until stop() is called."""
self._check_closed()
if self.is_running():
raise RuntimeError('Event loop is running.')
self._thread_id = threading.get_ident()
try:
while True:
try:
self._run_once()
except _StopError:
break
finally:
self._thread_id = None
def run_until_complete(self, future):
"""Run until the Future is done.
If the argument is a coroutine, it is wrapped in a Task.
WARNING: It would be disastrous to call run_until_complete()
with the same coroutine twice -- it would wrap it in two
different Tasks and that can't be good.
Return the Future's result, or raise its exception.
"""
self._check_closed()
new_task = not isinstance(future, futures.Future)
future = tasks.async(future, loop=self)
if new_task:
# An exception is raised if the future didn't complete, so there
# is no need to log the "destroy pending task" message
future._log_destroy_pending = False
future.add_done_callback(_run_until_complete_cb)
try:
self.run_forever()
except:
if new_task and future.done() and not future.cancelled():
# The coroutine raised a BaseException. Consume the exception
# to not log a warning, the caller doesn't have access to the
# local task.
future.exception()
raise
future.remove_done_callback(_run_until_complete_cb)
if not future.done():
raise RuntimeError('Event loop stopped before Future completed.')
return future.result()
def stop(self):
"""Stop running the event loop.
Every callback scheduled before stop() is called will run. Callbacks
scheduled after stop() is called will not run. However, those callbacks
will run if run_forever is called again later.
"""
self.call_soon(_raise_stop_error)
def close(self):
"""Close the event loop.
This clears the queues and shuts down the executor,
but does not wait for the executor to finish.
The event loop must not be running.
"""
if self.is_running():
raise RuntimeError("Cannot close a running event loop")
if self._closed:
return
if self._debug:
logger.debug("Close %r", self)
self._closed = True
self._ready.clear()
self._scheduled.clear()
executor = self._default_executor
if executor is not None:
self._default_executor = None
executor.shutdown(wait=False)
def is_closed(self):
"""Returns True if the event loop was closed."""
return self._closed
# On Python 3.3 and older, objects with a destructor part of a reference
# cycle are never destroyed. It's not more the case on Python 3.4 thanks
# to the PEP 442.
if sys.version_info >= (3, 4):
def __del__(self):
if not self.is_closed():
warnings.warn("unclosed event loop %r" % self, ResourceWarning)
if not self.is_running():
self.close()
def is_running(self):
"""Returns True if the event loop is running."""
return (self._thread_id is not None)
def time(self):
"""Return the time according to the event loop's clock.
This is a float expressed in seconds since an epoch, but the
epoch, precision, accuracy and drift are unspecified and may
differ per event loop.
"""
return time.monotonic()
def call_later(self, delay, callback, *args):
"""Arrange for a callback to be called at a given time.
Return a Handle: an opaque object with a cancel() method that
can be used to cancel the call.
The delay can be an int or float, expressed in seconds. It is
always relative to the current time.
Each callback will be called exactly once. If two callbacks
are scheduled for exactly the same time, it undefined which
will be called first.
Any positional arguments after the callback will be passed to
the callback when it is called.
"""
timer = self.call_at(self.time() + delay, callback, *args)
if timer._source_traceback:
del timer._source_traceback[-1]
return timer
def call_at(self, when, callback, *args):
"""Like call_later(), but uses an absolute time.
Absolute time corresponds to the event loop's time() method.
"""
if (coroutines.iscoroutine(callback)
or coroutines.iscoroutinefunction(callback)):
raise TypeError("coroutines cannot be used with call_at()")
self._check_closed()
if self._debug:
self._check_thread()
timer = events.TimerHandle(when, callback, args, self)
if timer._source_traceback:
del timer._source_traceback[-1]
heapq.heappush(self._scheduled, timer)
timer._scheduled = True
return timer
def call_soon(self, callback, *args):
"""Arrange for a callback to be called as soon as possible.
This operates as a FIFO queue: callbacks are called in the
order in which they are registered. Each callback will be
called exactly once.
Any positional arguments after the callback will be passed to
the callback when it is called.
"""
if self._debug:
self._check_thread()
handle = self._call_soon(callback, args)
if handle._source_traceback:
del handle._source_traceback[-1]
return handle
def _call_soon(self, callback, args):
if (coroutines.iscoroutine(callback)
or coroutines.iscoroutinefunction(callback)):
raise TypeError("coroutines cannot be used with call_soon()")
self._check_closed()
handle = events.Handle(callback, args, self)
if handle._source_traceback:
del handle._source_traceback[-1]
self._ready.append(handle)
return handle
def _check_thread(self):
"""Check that the current thread is the thread running the event loop.
Non-thread-safe methods of this class make this assumption and will
likely behave incorrectly when the assumption is violated.
Should only be called when (self._debug == True). The caller is
responsible for checking this condition for performance reasons.
"""
if self._thread_id is None:
return
thread_id = threading.get_ident()
if thread_id != self._thread_id:
raise RuntimeError(
"Non-thread-safe operation invoked on an event loop other "
"than the current one")
def call_soon_threadsafe(self, callback, *args):
"""Like call_soon(), but thread-safe."""
handle = self._call_soon(callback, args)
if handle._source_traceback:
del handle._source_traceback[-1]
self._write_to_self()
return handle
def run_in_executor(self, executor, callback, *args):
if (coroutines.iscoroutine(callback)
or coroutines.iscoroutinefunction(callback)):
raise TypeError("coroutines cannot be used with run_in_executor()")
self._check_closed()
if isinstance(callback, events.Handle):
assert not args
assert not isinstance(callback, events.TimerHandle)
if callback._cancelled:
f = futures.Future(loop=self)
f.set_result(None)
return f
callback, args = callback._callback, callback._args
if executor is None:
executor = self._default_executor
if executor is None:
executor = concurrent.futures.ThreadPoolExecutor(_MAX_WORKERS)
self._default_executor = executor
return futures.wrap_future(executor.submit(callback, *args), loop=self)
def set_default_executor(self, executor):
self._default_executor = executor
def _getaddrinfo_debug(self, host, port, family, type, proto, flags):
msg = ["%s:%r" % (host, port)]
if family:
msg.append('family=%r' % family)
if type:
msg.append('type=%r' % type)
if proto:
msg.append('proto=%r' % proto)
if flags:
msg.append('flags=%r' % flags)
msg = ', '.join(msg)
logger.debug('Get address info %s', msg)
t0 = self.time()
addrinfo = socket.getaddrinfo(host, port, family, type, proto, flags)
dt = self.time() - t0
msg = ('Getting address info %s took %.3f ms: %r'
% (msg, dt * 1e3, addrinfo))
if dt >= self.slow_callback_duration:
logger.info(msg)
else:
logger.debug(msg)
return addrinfo
def getaddrinfo(self, host, port, *,
family=0, type=0, proto=0, flags=0):
if self._debug:
return self.run_in_executor(None, self._getaddrinfo_debug,
host, port, family, type, proto, flags)
else:
return self.run_in_executor(None, socket.getaddrinfo,
host, port, family, type, proto, flags)
def getnameinfo(self, sockaddr, flags=0):
return self.run_in_executor(None, socket.getnameinfo, sockaddr, flags)
@coroutine
def create_connection(self, protocol_factory, host=None, port=None, *,
ssl=None, family=0, proto=0, flags=0, sock=None,
local_addr=None, server_hostname=None):
"""Connect to a TCP server.
Create a streaming transport connection to a given Internet host and
port: socket family AF_INET or socket.AF_INET6 depending on host (or
family if specified), socket type SOCK_STREAM. protocol_factory must be
a callable returning a protocol instance.
This method is a coroutine which will try to establish the connection
in the background. When successful, the coroutine returns a
(transport, protocol) pair.
"""
if server_hostname is not None and not ssl:
raise ValueError('server_hostname is only meaningful with ssl')
if server_hostname is None and ssl:
# Use host as default for server_hostname. It is an error
# if host is empty or not set, e.g. when an
# already-connected socket was passed or when only a port
# is given. To avoid this error, you can pass
# server_hostname='' -- this will bypass the hostname
# check. (This also means that if host is a numeric
# IP/IPv6 address, we will attempt to verify that exact
# address; this will probably fail, but it is possible to
# create a certificate for a specific IP address, so we
# don't judge it here.)
if not host:
raise ValueError('You must set server_hostname '
'when using ssl without a host')
server_hostname = host
if host is not None or port is not None:
if sock is not None:
raise ValueError(
'host/port and sock can not be specified at the same time')
f1 = self.getaddrinfo(
host, port, family=family,
type=socket.SOCK_STREAM, proto=proto, flags=flags)
fs = [f1]
if local_addr is not None:
f2 = self.getaddrinfo(
*local_addr, family=family,
type=socket.SOCK_STREAM, proto=proto, flags=flags)
fs.append(f2)
else:
f2 = None
yield from tasks.wait(fs, loop=self)
infos = f1.result()
if not infos:
raise OSError('getaddrinfo() returned empty list')
if f2 is not None:
laddr_infos = f2.result()
if not laddr_infos:
raise OSError('getaddrinfo() returned empty list')
exceptions = []
for family, type, proto, cname, address in infos:
try:
sock = socket.socket(family=family, type=type, proto=proto)
sock.setblocking(False)
if f2 is not None:
for _, _, _, _, laddr in laddr_infos:
try:
sock.bind(laddr)
break
except OSError as exc:
exc = OSError(
exc.errno, 'error while '
'attempting to bind on address '
'{!r}: {}'.format(
laddr, exc.strerror.lower()))
exceptions.append(exc)
else:
sock.close()
sock = None
continue
if self._debug:
logger.debug("connect %r to %r", sock, address)
yield from self.sock_connect(sock, address)
except OSError as exc:
if sock is not None:
sock.close()
exceptions.append(exc)
except:
if sock is not None:
sock.close()
raise
else:
break
else:
if len(exceptions) == 1:
raise exceptions[0]
else:
# If they all have the same str(), raise one.
model = str(exceptions[0])
if all(str(exc) == model for exc in exceptions):
raise exceptions[0]
# Raise a combined exception so the user can see all
# the various error messages.
raise OSError('Multiple exceptions: {}'.format(
', '.join(str(exc) for exc in exceptions)))
elif sock is None:
raise ValueError(
'host and port was not specified and no sock specified')
sock.setblocking(False)
transport, protocol = yield from self._create_connection_transport(
sock, protocol_factory, ssl, server_hostname)
if self._debug:
# Get the socket from the transport because SSL transport closes
# the old socket and creates a new SSL socket
sock = transport.get_extra_info('socket')
logger.debug("%r connected to %s:%r: (%r, %r)",
sock, host, port, transport, protocol)
return transport, protocol
@coroutine
def _create_connection_transport(self, sock, protocol_factory, ssl,
server_hostname):
protocol = protocol_factory()
waiter = futures.Future(loop=self)
if ssl:
sslcontext = None if isinstance(ssl, bool) else ssl
transport = self._make_ssl_transport(
sock, protocol, sslcontext, waiter,
server_side=False, server_hostname=server_hostname)
else:
transport = self._make_socket_transport(sock, protocol, waiter)
try:
yield from waiter
except:
transport.close()
raise
return transport, protocol
@coroutine
def create_datagram_endpoint(self, protocol_factory,
local_addr=None, remote_addr=None, *,
family=0, proto=0, flags=0):
"""Create datagram connection."""
if not (local_addr or remote_addr):
if family == 0:
raise ValueError('unexpected address family')
addr_pairs_info = (((family, proto), (None, None)),)
else:
# join address by (family, protocol)
addr_infos = collections.OrderedDict()
for idx, addr in ((0, local_addr), (1, remote_addr)):
if addr is not None:
assert isinstance(addr, tuple) and len(addr) == 2, (
'2-tuple is expected')
infos = yield from self.getaddrinfo(
*addr, family=family, type=socket.SOCK_DGRAM,
proto=proto, flags=flags)
if not infos:
raise OSError('getaddrinfo() returned empty list')
for fam, _, pro, _, address in infos:
key = (fam, pro)
if key not in addr_infos:
addr_infos[key] = [None, None]
addr_infos[key][idx] = address
# each addr has to have info for each (family, proto) pair
addr_pairs_info = [
(key, addr_pair) for key, addr_pair in addr_infos.items()
if not ((local_addr and addr_pair[0] is None) or
(remote_addr and addr_pair[1] is None))]
if not addr_pairs_info:
raise ValueError('can not get address information')
exceptions = []
for ((family, proto),
(local_address, remote_address)) in addr_pairs_info:
sock = None
r_addr = None
try:
sock = socket.socket(
family=family, type=socket.SOCK_DGRAM, proto=proto)
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
sock.setblocking(False)
if local_addr:
sock.bind(local_address)
if remote_addr:
yield from self.sock_connect(sock, remote_address)
r_addr = remote_address
except OSError as exc:
if sock is not None:
sock.close()
exceptions.append(exc)
except:
if sock is not None:
sock.close()
raise
else:
break
else:
raise exceptions[0]
protocol = protocol_factory()
waiter = futures.Future(loop=self)
transport = self._make_datagram_transport(sock, protocol, r_addr,
waiter)
if self._debug:
if local_addr:
logger.info("Datagram endpoint local_addr=%r remote_addr=%r "
"created: (%r, %r)",
local_addr, remote_addr, transport, protocol)
else:
logger.debug("Datagram endpoint remote_addr=%r created: "
"(%r, %r)",
remote_addr, transport, protocol)
try:
yield from waiter
except:
transport.close()
raise
return transport, protocol
@coroutine
def create_server(self, protocol_factory, host=None, port=None,
*,
family=socket.AF_UNSPEC,
flags=socket.AI_PASSIVE,
sock=None,
backlog=100,
ssl=None,
reuse_address=None):
"""Create a TCP server bound to host and port.
Return a Server object which can be used to stop the service.
This method is a coroutine.
"""
if isinstance(ssl, bool):
raise TypeError('ssl argument must be an SSLContext or None')
if host is not None or port is not None:
if sock is not None:
raise ValueError(
'host/port and sock can not be specified at the same time')
AF_INET6 = getattr(socket, 'AF_INET6', 0)
if reuse_address is None:
reuse_address = os.name == 'posix' and sys.platform != 'cygwin'
sockets = []
if host == '':
host = None
infos = yield from self.getaddrinfo(
host, port, family=family,
type=socket.SOCK_STREAM, proto=0, flags=flags)
if not infos:
raise OSError('getaddrinfo() returned empty list')
completed = False
try:
for res in infos:
af, socktype, proto, canonname, sa = res
try:
sock = socket.socket(af, socktype, proto)
except socket.error:
# Assume it's a bad family/type/protocol combination.
if self._debug:
logger.warning('create_server() failed to create '
'socket.socket(%r, %r, %r)',
af, socktype, proto, exc_info=True)
continue
sockets.append(sock)
if reuse_address:
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR,
True)
# Disable IPv4/IPv6 dual stack support (enabled by
# default on Linux) which makes a single socket
# listen on both address families.
if af == AF_INET6 and hasattr(socket, 'IPPROTO_IPV6'):
sock.setsockopt(socket.IPPROTO_IPV6,
socket.IPV6_V6ONLY,
True)
try:
sock.bind(sa)
except OSError as err:
raise OSError(err.errno, 'error while attempting '
'to bind on address %r: %s'
% (sa, err.strerror.lower()))
completed = True
finally:
if not completed:
for sock in sockets:
sock.close()
else:
if sock is None:
raise ValueError('Neither host/port nor sock were specified')
sockets = [sock]
server = Server(self, sockets)
for sock in sockets:
sock.listen(backlog)
sock.setblocking(False)
self._start_serving(protocol_factory, sock, ssl, server)
if self._debug:
logger.info("%r is serving", server)
return server
@coroutine
def connect_read_pipe(self, protocol_factory, pipe):
protocol = protocol_factory()
waiter = futures.Future(loop=self)
transport = self._make_read_pipe_transport(pipe, protocol, waiter)
try:
yield from waiter
except:
transport.close()
raise
if self._debug:
logger.debug('Read pipe %r connected: (%r, %r)',
pipe.fileno(), transport, protocol)
return transport, protocol
@coroutine
def connect_write_pipe(self, protocol_factory, pipe):
protocol = protocol_factory()
waiter = futures.Future(loop=self)
transport = self._make_write_pipe_transport(pipe, protocol, waiter)
try:
yield from waiter
except:
transport.close()
raise
if self._debug:
logger.debug('Write pipe %r connected: (%r, %r)',
pipe.fileno(), transport, protocol)
return transport, protocol
def _log_subprocess(self, msg, stdin, stdout, stderr):
info = [msg]
if stdin is not None:
info.append('stdin=%s' % _format_pipe(stdin))
if stdout is not None and stderr == subprocess.STDOUT:
info.append('stdout=stderr=%s' % _format_pipe(stdout))
else:
if stdout is not None:
info.append('stdout=%s' % _format_pipe(stdout))
if stderr is not None:
info.append('stderr=%s' % _format_pipe(stderr))
logger.debug(' '.join(info))
@coroutine
def subprocess_shell(self, protocol_factory, cmd, *, stdin=subprocess.PIPE,
stdout=subprocess.PIPE, stderr=subprocess.PIPE,
universal_newlines=False, shell=True, bufsize=0,
**kwargs):
if not isinstance(cmd, (bytes, str)):
raise ValueError("cmd must be a string")
if universal_newlines:
raise ValueError("universal_newlines must be False")
if not shell:
raise ValueError("shell must be True")
if bufsize != 0:
raise ValueError("bufsize must be 0")
protocol = protocol_factory()
if self._debug:
# don't log parameters: they may contain sensitive information
# (password) and may be too long
debug_log = 'run shell command %r' % cmd
self._log_subprocess(debug_log, stdin, stdout, stderr)
transport = yield from self._make_subprocess_transport(
protocol, cmd, True, stdin, stdout, stderr, bufsize, **kwargs)
if self._debug:
logger.info('%s: %r' % (debug_log, transport))
return transport, protocol
@coroutine
def subprocess_exec(self, protocol_factory, program, *args,
stdin=subprocess.PIPE, stdout=subprocess.PIPE,
stderr=subprocess.PIPE, universal_newlines=False,
shell=False, bufsize=0, **kwargs):
if universal_newlines:
raise ValueError("universal_newlines must be False")
if shell:
raise ValueError("shell must be False")
if bufsize != 0:
raise ValueError("bufsize must be 0")
popen_args = (program,) + args
for arg in popen_args:
if not isinstance(arg, (str, bytes)):
raise TypeError("program arguments must be "
"a bytes or text string, not %s"
% type(arg).__name__)
protocol = protocol_factory()
if self._debug:
# don't log parameters: they may contain sensitive information
# (password) and may be too long
debug_log = 'execute program %r' % program
self._log_subprocess(debug_log, stdin, stdout, stderr)
transport = yield from self._make_subprocess_transport(
protocol, popen_args, False, stdin, stdout, stderr,
bufsize, **kwargs)
if self._debug:
logger.info('%s: %r' % (debug_log, transport))
return transport, protocol
def set_exception_handler(self, handler):
"""Set handler as the new event loop exception handler.
If handler is None, the default exception handler will
be set.
If handler is a callable object, it should have a
signature matching '(loop, context)', where 'loop'
will be a reference to the active event loop, 'context'
will be a dict object (see `call_exception_handler()`
documentation for details about context).
"""
if handler is not None and not callable(handler):
raise TypeError('A callable object or None is expected, '
'got {!r}'.format(handler))
self._exception_handler = handler
def default_exception_handler(self, context):
"""Default exception handler.
This is called when an exception occurs and no exception
handler is set, and can be called by a custom exception
handler that wants to defer to the default behavior.
The context parameter has the same meaning as in
`call_exception_handler()`.
"""
message = context.get('message')
if not message:
message = 'Unhandled exception in event loop'
exception = context.get('exception')
if exception is not None:
exc_info = (type(exception), exception, exception.__traceback__)
else:
exc_info = False
if ('source_traceback' not in context
and self._current_handle is not None
and self._current_handle._source_traceback):
context['handle_traceback'] = self._current_handle._source_traceback
log_lines = [message]
for key in sorted(context):
if key in {'message', 'exception'}:
continue
value = context[key]
if key == 'source_traceback':
tb = ''.join(traceback.format_list(value))
value = 'Object created at (most recent call last):\n'
value += tb.rstrip()
elif key == 'handle_traceback':
tb = ''.join(traceback.format_list(value))
value = 'Handle created at (most recent call last):\n'
value += tb.rstrip()
else:
value = repr(value)
log_lines.append('{}: {}'.format(key, value))
logger.error('\n'.join(log_lines), exc_info=exc_info)
def call_exception_handler(self, context):
"""Call the current event loop's exception handler.
The context argument is a dict containing the following keys:
- 'message': Error message;
- 'exception' (optional): Exception object;
- 'future' (optional): Future instance;
- 'handle' (optional): Handle instance;
- 'protocol' (optional): Protocol instance;
- 'transport' (optional): Transport instance;
- 'socket' (optional): Socket instance.
New keys maybe introduced in the future.
Note: do not overload this method in an event loop subclass.
For custom exception handling, use the
`set_exception_handler()` method.
"""
if self._exception_handler is None:
try:
self.default_exception_handler(context)
except Exception:
# Second protection layer for unexpected errors
# in the default implementation, as well as for subclassed
# event loops with overloaded "default_exception_handler".
logger.error('Exception in default exception handler',
exc_info=True)
else:
try:
self._exception_handler(self, context)
except Exception as exc:
# Exception in the user set custom exception handler.
try:
# Let's try default handler.
self.default_exception_handler({
'message': 'Unhandled error in exception handler',
'exception': exc,
'context': context,
})
except Exception:
# Guard 'default_exception_handler' in case it is
# overloaded.
logger.error('Exception in default exception handler '
'while handling an unexpected error '
'in custom exception handler',
exc_info=True)
def _add_callback(self, handle):
"""Add a Handle to _scheduled (TimerHandle) or _ready."""
assert isinstance(handle, events.Handle), 'A Handle is required here'
if handle._cancelled:
return
assert not isinstance(handle, events.TimerHandle)
self._ready.append(handle)
def _add_callback_signalsafe(self, handle):
"""Like _add_callback() but called from a signal handler."""
self._add_callback(handle)
self._write_to_self()
def _timer_handle_cancelled(self, handle):
"""Notification that a TimerHandle has been cancelled."""
if handle._scheduled:
self._timer_cancelled_count += 1
def _run_once(self):
"""Run one full iteration of the event loop.
This calls all currently ready callbacks, polls for I/O,
schedules the resulting callbacks, and finally schedules
'call_later' callbacks.
"""
sched_count = len(self._scheduled)
if (sched_count > _MIN_SCHEDULED_TIMER_HANDLES and
self._timer_cancelled_count / sched_count >
_MIN_CANCELLED_TIMER_HANDLES_FRACTION):
# Remove delayed calls that were cancelled if their number
# is too high
new_scheduled = []
for handle in self._scheduled:
if handle._cancelled:
handle._scheduled = False
else:
new_scheduled.append(handle)
heapq.heapify(new_scheduled)
self._scheduled = new_scheduled
self._timer_cancelled_count = 0
else:
# Remove delayed calls that were cancelled from head of queue.
while self._scheduled and self._scheduled[0]._cancelled:
self._timer_cancelled_count -= 1
handle = heapq.heappop(self._scheduled)
handle._scheduled = False
timeout = None
if self._ready:
timeout = 0
elif self._scheduled:
# Compute the desired timeout.
when = self._scheduled[0]._when
timeout = max(0, when - self.time())
if self._debug and timeout != 0:
t0 = self.time()
event_list = self._selector.select(timeout)
dt = self.time() - t0
if dt >= 1.0:
level = logging.INFO
else:
level = logging.DEBUG
nevent = len(event_list)
if timeout is None:
logger.log(level, 'poll took %.3f ms: %s events',
dt * 1e3, nevent)
elif nevent:
logger.log(level,
'poll %.3f ms took %.3f ms: %s events',
timeout * 1e3, dt * 1e3, nevent)
elif dt >= 1.0:
logger.log(level,
'poll %.3f ms took %.3f ms: timeout',
timeout * 1e3, dt * 1e3)
else:
event_list = self._selector.select(timeout)
self._process_events(event_list)
# Handle 'later' callbacks that are ready.
end_time = self.time() + self._clock_resolution
while self._scheduled:
handle = self._scheduled[0]
if handle._when >= end_time:
break
handle = heapq.heappop(self._scheduled)
handle._scheduled = False
self._ready.append(handle)
# This is the only place where callbacks are actually *called*.
# All other places just add them to ready.
# Note: We run all currently scheduled callbacks, but not any
# callbacks scheduled by callbacks run this time around --
# they will be run the next time (after another I/O poll).
# Use an idiom that is thread-safe without using locks.
ntodo = len(self._ready)
for i in range(ntodo):
handle = self._ready.popleft()
if handle._cancelled:
continue
if self._debug:
try:
self._current_handle = handle
t0 = self.time()
handle._run()
dt = self.time() - t0
if dt >= self.slow_callback_duration:
logger.warning('Executing %s took %.3f seconds',
_format_handle(handle), dt)
finally:
self._current_handle = None
else:
handle._run()
handle = None # Needed to break cycles when an exception occurs.
def get_debug(self):
return self._debug
def set_debug(self, enabled):
self._debug = enabled
|