Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 1 | """Base implementation of event loop. |
| 2 | |
| 3 | The event loop can be broken up into a multiplexer (the part |
| 4 | responsible for notifying us of IO events) and the event loop proper, |
| 5 | which wraps a multiplexer with functionality for scheduling callbacks, |
| 6 | immediately or at a given time in the future. |
| 7 | |
| 8 | Whenever a public API takes a callback, subsequent positional |
| 9 | arguments will be passed to the callback if/when it is called. This |
| 10 | avoids the proliferation of trivial lambdas implementing closures. |
| 11 | Keyword arguments for the callback are not supported; this is a |
| 12 | conscious design decision, leaving the door open for keyword arguments |
| 13 | to modify the meaning of the API call itself. |
| 14 | """ |
| 15 | |
| 16 | |
| 17 | import collections |
| 18 | import concurrent.futures |
| 19 | import heapq |
| 20 | import logging |
| 21 | import socket |
| 22 | import subprocess |
| 23 | import time |
| 24 | import os |
| 25 | import sys |
| 26 | |
| 27 | from . import events |
| 28 | from . import futures |
| 29 | from . import tasks |
Guido van Rossum | fc29e0f | 2013-10-17 15:39:45 -0700 | [diff] [blame] | 30 | from .log import logger |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 31 | |
| 32 | |
| 33 | __all__ = ['BaseEventLoop', 'Server'] |
| 34 | |
| 35 | |
| 36 | # Argument for default thread pool executor creation. |
| 37 | _MAX_WORKERS = 5 |
| 38 | |
| 39 | |
| 40 | class _StopError(BaseException): |
| 41 | """Raised to stop the event loop.""" |
| 42 | |
| 43 | |
Victor Stinner | 1b0580b | 2014-02-13 09:24:37 +0100 | [diff] [blame] | 44 | def _check_resolved_address(sock, address): |
| 45 | # Ensure that the address is already resolved to avoid the trap of hanging |
| 46 | # the entire event loop when the address requires doing a DNS lookup. |
| 47 | family = sock.family |
Victor Stinner | d1a727a | 2014-02-20 16:43:09 +0100 | [diff] [blame^] | 48 | if family == socket.AF_INET: |
| 49 | host, port = address |
| 50 | elif family == socket.AF_INET6: |
| 51 | host, port, flow_info, scope_id = address |
| 52 | else: |
Victor Stinner | 1b0580b | 2014-02-13 09:24:37 +0100 | [diff] [blame] | 53 | return |
| 54 | |
Victor Stinner | 1b0580b | 2014-02-13 09:24:37 +0100 | [diff] [blame] | 55 | type_mask = 0 |
| 56 | if hasattr(socket, 'SOCK_NONBLOCK'): |
| 57 | type_mask |= socket.SOCK_NONBLOCK |
| 58 | if hasattr(socket, 'SOCK_CLOEXEC'): |
| 59 | type_mask |= socket.SOCK_CLOEXEC |
| 60 | # Use getaddrinfo(AI_NUMERICHOST) to ensure that the address is |
| 61 | # already resolved. |
| 62 | try: |
| 63 | socket.getaddrinfo(host, port, |
| 64 | family=family, |
| 65 | type=(sock.type & ~type_mask), |
| 66 | proto=sock.proto, |
| 67 | flags=socket.AI_NUMERICHOST) |
| 68 | except socket.gaierror as err: |
| 69 | raise ValueError("address must be resolved (IP address), got %r: %s" |
| 70 | % (address, err)) |
| 71 | |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 72 | def _raise_stop_error(*args): |
| 73 | raise _StopError |
| 74 | |
| 75 | |
| 76 | class Server(events.AbstractServer): |
| 77 | |
| 78 | def __init__(self, loop, sockets): |
| 79 | self.loop = loop |
| 80 | self.sockets = sockets |
| 81 | self.active_count = 0 |
| 82 | self.waiters = [] |
| 83 | |
| 84 | def attach(self, transport): |
| 85 | assert self.sockets is not None |
| 86 | self.active_count += 1 |
| 87 | |
| 88 | def detach(self, transport): |
| 89 | assert self.active_count > 0 |
| 90 | self.active_count -= 1 |
| 91 | if self.active_count == 0 and self.sockets is None: |
| 92 | self._wakeup() |
| 93 | |
| 94 | def close(self): |
| 95 | sockets = self.sockets |
| 96 | if sockets is not None: |
| 97 | self.sockets = None |
| 98 | for sock in sockets: |
| 99 | self.loop._stop_serving(sock) |
| 100 | if self.active_count == 0: |
| 101 | self._wakeup() |
| 102 | |
| 103 | def _wakeup(self): |
| 104 | waiters = self.waiters |
| 105 | self.waiters = None |
| 106 | for waiter in waiters: |
| 107 | if not waiter.done(): |
| 108 | waiter.set_result(waiter) |
| 109 | |
| 110 | @tasks.coroutine |
| 111 | def wait_closed(self): |
| 112 | if self.sockets is None or self.waiters is None: |
| 113 | return |
| 114 | waiter = futures.Future(loop=self.loop) |
| 115 | self.waiters.append(waiter) |
| 116 | yield from waiter |
| 117 | |
| 118 | |
| 119 | class BaseEventLoop(events.AbstractEventLoop): |
| 120 | |
| 121 | def __init__(self): |
| 122 | self._ready = collections.deque() |
| 123 | self._scheduled = [] |
| 124 | self._default_executor = None |
| 125 | self._internal_fds = 0 |
| 126 | self._running = False |
Victor Stinner | ed1654f | 2014-02-10 23:42:32 +0100 | [diff] [blame] | 127 | self._clock_resolution = time.get_clock_info('monotonic').resolution |
Yury Selivanov | 569efa2 | 2014-02-18 18:02:19 -0500 | [diff] [blame] | 128 | self._exception_handler = None |
Victor Stinner | 0f3e6bc | 2014-02-19 23:15:02 +0100 | [diff] [blame] | 129 | self._debug = False |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 130 | |
| 131 | def _make_socket_transport(self, sock, protocol, waiter=None, *, |
| 132 | extra=None, server=None): |
| 133 | """Create socket transport.""" |
| 134 | raise NotImplementedError |
| 135 | |
| 136 | def _make_ssl_transport(self, rawsock, protocol, sslcontext, waiter, *, |
| 137 | server_side=False, server_hostname=None, |
| 138 | extra=None, server=None): |
| 139 | """Create SSL transport.""" |
| 140 | raise NotImplementedError |
| 141 | |
| 142 | def _make_datagram_transport(self, sock, protocol, |
| 143 | address=None, extra=None): |
| 144 | """Create datagram transport.""" |
| 145 | raise NotImplementedError |
| 146 | |
| 147 | def _make_read_pipe_transport(self, pipe, protocol, waiter=None, |
| 148 | extra=None): |
| 149 | """Create read pipe transport.""" |
| 150 | raise NotImplementedError |
| 151 | |
| 152 | def _make_write_pipe_transport(self, pipe, protocol, waiter=None, |
| 153 | extra=None): |
| 154 | """Create write pipe transport.""" |
| 155 | raise NotImplementedError |
| 156 | |
| 157 | @tasks.coroutine |
| 158 | def _make_subprocess_transport(self, protocol, args, shell, |
| 159 | stdin, stdout, stderr, bufsize, |
| 160 | extra=None, **kwargs): |
| 161 | """Create subprocess transport.""" |
| 162 | raise NotImplementedError |
| 163 | |
| 164 | def _read_from_self(self): |
| 165 | """XXX""" |
| 166 | raise NotImplementedError |
| 167 | |
| 168 | def _write_to_self(self): |
| 169 | """XXX""" |
| 170 | raise NotImplementedError |
| 171 | |
| 172 | def _process_events(self, event_list): |
| 173 | """Process selector events.""" |
| 174 | raise NotImplementedError |
| 175 | |
| 176 | def run_forever(self): |
| 177 | """Run until stop() is called.""" |
| 178 | if self._running: |
| 179 | raise RuntimeError('Event loop is running.') |
| 180 | self._running = True |
| 181 | try: |
| 182 | while True: |
| 183 | try: |
| 184 | self._run_once() |
| 185 | except _StopError: |
| 186 | break |
| 187 | finally: |
| 188 | self._running = False |
| 189 | |
| 190 | def run_until_complete(self, future): |
| 191 | """Run until the Future is done. |
| 192 | |
| 193 | If the argument is a coroutine, it is wrapped in a Task. |
| 194 | |
| 195 | XXX TBD: It would be disastrous to call run_until_complete() |
| 196 | with the same coroutine twice -- it would wrap it in two |
| 197 | different Tasks and that can't be good. |
| 198 | |
| 199 | Return the Future's result, or raise its exception. |
| 200 | """ |
| 201 | future = tasks.async(future, loop=self) |
| 202 | future.add_done_callback(_raise_stop_error) |
| 203 | self.run_forever() |
| 204 | future.remove_done_callback(_raise_stop_error) |
| 205 | if not future.done(): |
| 206 | raise RuntimeError('Event loop stopped before Future completed.') |
| 207 | |
| 208 | return future.result() |
| 209 | |
| 210 | def stop(self): |
| 211 | """Stop running the event loop. |
| 212 | |
| 213 | Every callback scheduled before stop() is called will run. |
| 214 | Callback scheduled after stop() is called won't. However, |
| 215 | those callbacks will run if run() is called again later. |
| 216 | """ |
| 217 | self.call_soon(_raise_stop_error) |
| 218 | |
Antoine Pitrou | 4ca7355 | 2013-10-20 00:54:10 +0200 | [diff] [blame] | 219 | def close(self): |
Guido van Rossum | e3f52ef | 2013-11-01 14:19:04 -0700 | [diff] [blame] | 220 | """Close the event loop. |
| 221 | |
| 222 | This clears the queues and shuts down the executor, |
| 223 | but does not wait for the executor to finish. |
| 224 | """ |
Antoine Pitrou | 4ca7355 | 2013-10-20 00:54:10 +0200 | [diff] [blame] | 225 | self._ready.clear() |
| 226 | self._scheduled.clear() |
| 227 | executor = self._default_executor |
| 228 | if executor is not None: |
| 229 | self._default_executor = None |
| 230 | executor.shutdown(wait=False) |
| 231 | |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 232 | def is_running(self): |
| 233 | """Returns running status of event loop.""" |
| 234 | return self._running |
| 235 | |
| 236 | def time(self): |
| 237 | """Return the time according to the event loop's clock.""" |
| 238 | return time.monotonic() |
| 239 | |
| 240 | def call_later(self, delay, callback, *args): |
| 241 | """Arrange for a callback to be called at a given time. |
| 242 | |
| 243 | Return a Handle: an opaque object with a cancel() method that |
| 244 | can be used to cancel the call. |
| 245 | |
| 246 | The delay can be an int or float, expressed in seconds. It is |
| 247 | always a relative time. |
| 248 | |
| 249 | Each callback will be called exactly once. If two callbacks |
| 250 | are scheduled for exactly the same time, it undefined which |
| 251 | will be called first. |
| 252 | |
| 253 | Any positional arguments after the callback will be passed to |
| 254 | the callback when it is called. |
| 255 | """ |
| 256 | return self.call_at(self.time() + delay, callback, *args) |
| 257 | |
| 258 | def call_at(self, when, callback, *args): |
| 259 | """Like call_later(), but uses an absolute time.""" |
Victor Stinner | 9af4a24 | 2014-02-11 11:34:30 +0100 | [diff] [blame] | 260 | if tasks.iscoroutinefunction(callback): |
| 261 | raise TypeError("coroutines cannot be used with call_at()") |
Yury Selivanov | 569efa2 | 2014-02-18 18:02:19 -0500 | [diff] [blame] | 262 | timer = events.TimerHandle(when, callback, args, self) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 263 | heapq.heappush(self._scheduled, timer) |
| 264 | return timer |
| 265 | |
| 266 | def call_soon(self, callback, *args): |
| 267 | """Arrange for a callback to be called as soon as possible. |
| 268 | |
| 269 | This operates as a FIFO queue, callbacks are called in the |
| 270 | order in which they are registered. Each callback will be |
| 271 | called exactly once. |
| 272 | |
| 273 | Any positional arguments after the callback will be passed to |
| 274 | the callback when it is called. |
| 275 | """ |
Victor Stinner | 9af4a24 | 2014-02-11 11:34:30 +0100 | [diff] [blame] | 276 | if tasks.iscoroutinefunction(callback): |
| 277 | raise TypeError("coroutines cannot be used with call_soon()") |
Yury Selivanov | 569efa2 | 2014-02-18 18:02:19 -0500 | [diff] [blame] | 278 | handle = events.Handle(callback, args, self) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 279 | self._ready.append(handle) |
| 280 | return handle |
| 281 | |
| 282 | def call_soon_threadsafe(self, callback, *args): |
| 283 | """XXX""" |
| 284 | handle = self.call_soon(callback, *args) |
| 285 | self._write_to_self() |
| 286 | return handle |
| 287 | |
| 288 | def run_in_executor(self, executor, callback, *args): |
Victor Stinner | 9af4a24 | 2014-02-11 11:34:30 +0100 | [diff] [blame] | 289 | if tasks.iscoroutinefunction(callback): |
| 290 | raise TypeError("coroutines cannot be used with run_in_executor()") |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 291 | if isinstance(callback, events.Handle): |
| 292 | assert not args |
| 293 | assert not isinstance(callback, events.TimerHandle) |
| 294 | if callback._cancelled: |
| 295 | f = futures.Future(loop=self) |
| 296 | f.set_result(None) |
| 297 | return f |
| 298 | callback, args = callback._callback, callback._args |
| 299 | if executor is None: |
| 300 | executor = self._default_executor |
| 301 | if executor is None: |
| 302 | executor = concurrent.futures.ThreadPoolExecutor(_MAX_WORKERS) |
| 303 | self._default_executor = executor |
| 304 | return futures.wrap_future(executor.submit(callback, *args), loop=self) |
| 305 | |
| 306 | def set_default_executor(self, executor): |
| 307 | self._default_executor = executor |
| 308 | |
| 309 | def getaddrinfo(self, host, port, *, |
| 310 | family=0, type=0, proto=0, flags=0): |
| 311 | return self.run_in_executor(None, socket.getaddrinfo, |
| 312 | host, port, family, type, proto, flags) |
| 313 | |
| 314 | def getnameinfo(self, sockaddr, flags=0): |
| 315 | return self.run_in_executor(None, socket.getnameinfo, sockaddr, flags) |
| 316 | |
| 317 | @tasks.coroutine |
| 318 | def create_connection(self, protocol_factory, host=None, port=None, *, |
| 319 | ssl=None, family=0, proto=0, flags=0, sock=None, |
Guido van Rossum | 21c85a7 | 2013-11-01 14:16:54 -0700 | [diff] [blame] | 320 | local_addr=None, server_hostname=None): |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 321 | """XXX""" |
Guido van Rossum | 21c85a7 | 2013-11-01 14:16:54 -0700 | [diff] [blame] | 322 | if server_hostname is not None and not ssl: |
| 323 | raise ValueError('server_hostname is only meaningful with ssl') |
| 324 | |
| 325 | if server_hostname is None and ssl: |
| 326 | # Use host as default for server_hostname. It is an error |
| 327 | # if host is empty or not set, e.g. when an |
| 328 | # already-connected socket was passed or when only a port |
| 329 | # is given. To avoid this error, you can pass |
| 330 | # server_hostname='' -- this will bypass the hostname |
| 331 | # check. (This also means that if host is a numeric |
| 332 | # IP/IPv6 address, we will attempt to verify that exact |
| 333 | # address; this will probably fail, but it is possible to |
| 334 | # create a certificate for a specific IP address, so we |
| 335 | # don't judge it here.) |
| 336 | if not host: |
| 337 | raise ValueError('You must set server_hostname ' |
| 338 | 'when using ssl without a host') |
| 339 | server_hostname = host |
Guido van Rossum | a8d630a | 2013-11-01 14:20:55 -0700 | [diff] [blame] | 340 | |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 341 | if host is not None or port is not None: |
| 342 | if sock is not None: |
| 343 | raise ValueError( |
| 344 | 'host/port and sock can not be specified at the same time') |
| 345 | |
| 346 | f1 = self.getaddrinfo( |
| 347 | host, port, family=family, |
| 348 | type=socket.SOCK_STREAM, proto=proto, flags=flags) |
| 349 | fs = [f1] |
| 350 | if local_addr is not None: |
| 351 | f2 = self.getaddrinfo( |
| 352 | *local_addr, family=family, |
| 353 | type=socket.SOCK_STREAM, proto=proto, flags=flags) |
| 354 | fs.append(f2) |
| 355 | else: |
| 356 | f2 = None |
| 357 | |
| 358 | yield from tasks.wait(fs, loop=self) |
| 359 | |
| 360 | infos = f1.result() |
| 361 | if not infos: |
| 362 | raise OSError('getaddrinfo() returned empty list') |
| 363 | if f2 is not None: |
| 364 | laddr_infos = f2.result() |
| 365 | if not laddr_infos: |
| 366 | raise OSError('getaddrinfo() returned empty list') |
| 367 | |
| 368 | exceptions = [] |
| 369 | for family, type, proto, cname, address in infos: |
| 370 | try: |
| 371 | sock = socket.socket(family=family, type=type, proto=proto) |
| 372 | sock.setblocking(False) |
| 373 | if f2 is not None: |
| 374 | for _, _, _, _, laddr in laddr_infos: |
| 375 | try: |
| 376 | sock.bind(laddr) |
| 377 | break |
| 378 | except OSError as exc: |
| 379 | exc = OSError( |
| 380 | exc.errno, 'error while ' |
| 381 | 'attempting to bind on address ' |
| 382 | '{!r}: {}'.format( |
| 383 | laddr, exc.strerror.lower())) |
| 384 | exceptions.append(exc) |
| 385 | else: |
| 386 | sock.close() |
| 387 | sock = None |
| 388 | continue |
| 389 | yield from self.sock_connect(sock, address) |
| 390 | except OSError as exc: |
| 391 | if sock is not None: |
| 392 | sock.close() |
| 393 | exceptions.append(exc) |
| 394 | else: |
| 395 | break |
| 396 | else: |
| 397 | if len(exceptions) == 1: |
| 398 | raise exceptions[0] |
| 399 | else: |
| 400 | # If they all have the same str(), raise one. |
| 401 | model = str(exceptions[0]) |
| 402 | if all(str(exc) == model for exc in exceptions): |
| 403 | raise exceptions[0] |
| 404 | # Raise a combined exception so the user can see all |
| 405 | # the various error messages. |
| 406 | raise OSError('Multiple exceptions: {}'.format( |
| 407 | ', '.join(str(exc) for exc in exceptions))) |
| 408 | |
| 409 | elif sock is None: |
| 410 | raise ValueError( |
| 411 | 'host and port was not specified and no sock specified') |
| 412 | |
| 413 | sock.setblocking(False) |
| 414 | |
Yury Selivanov | b057c52 | 2014-02-18 12:15:06 -0500 | [diff] [blame] | 415 | transport, protocol = yield from self._create_connection_transport( |
| 416 | sock, protocol_factory, ssl, server_hostname) |
| 417 | return transport, protocol |
| 418 | |
| 419 | @tasks.coroutine |
| 420 | def _create_connection_transport(self, sock, protocol_factory, ssl, |
| 421 | server_hostname): |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 422 | protocol = protocol_factory() |
| 423 | waiter = futures.Future(loop=self) |
| 424 | if ssl: |
| 425 | sslcontext = None if isinstance(ssl, bool) else ssl |
| 426 | transport = self._make_ssl_transport( |
| 427 | sock, protocol, sslcontext, waiter, |
Guido van Rossum | 21c85a7 | 2013-11-01 14:16:54 -0700 | [diff] [blame] | 428 | server_side=False, server_hostname=server_hostname) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 429 | else: |
| 430 | transport = self._make_socket_transport(sock, protocol, waiter) |
| 431 | |
| 432 | yield from waiter |
| 433 | return transport, protocol |
| 434 | |
| 435 | @tasks.coroutine |
| 436 | def create_datagram_endpoint(self, protocol_factory, |
| 437 | local_addr=None, remote_addr=None, *, |
| 438 | family=0, proto=0, flags=0): |
| 439 | """Create datagram connection.""" |
| 440 | if not (local_addr or remote_addr): |
| 441 | if family == 0: |
| 442 | raise ValueError('unexpected address family') |
| 443 | addr_pairs_info = (((family, proto), (None, None)),) |
| 444 | else: |
| 445 | # join addresss by (family, protocol) |
| 446 | addr_infos = collections.OrderedDict() |
| 447 | for idx, addr in ((0, local_addr), (1, remote_addr)): |
| 448 | if addr is not None: |
| 449 | assert isinstance(addr, tuple) and len(addr) == 2, ( |
| 450 | '2-tuple is expected') |
| 451 | |
| 452 | infos = yield from self.getaddrinfo( |
| 453 | *addr, family=family, type=socket.SOCK_DGRAM, |
| 454 | proto=proto, flags=flags) |
| 455 | if not infos: |
| 456 | raise OSError('getaddrinfo() returned empty list') |
| 457 | |
| 458 | for fam, _, pro, _, address in infos: |
| 459 | key = (fam, pro) |
| 460 | if key not in addr_infos: |
| 461 | addr_infos[key] = [None, None] |
| 462 | addr_infos[key][idx] = address |
| 463 | |
| 464 | # each addr has to have info for each (family, proto) pair |
| 465 | addr_pairs_info = [ |
| 466 | (key, addr_pair) for key, addr_pair in addr_infos.items() |
| 467 | if not ((local_addr and addr_pair[0] is None) or |
| 468 | (remote_addr and addr_pair[1] is None))] |
| 469 | |
| 470 | if not addr_pairs_info: |
| 471 | raise ValueError('can not get address information') |
| 472 | |
| 473 | exceptions = [] |
| 474 | |
| 475 | for ((family, proto), |
| 476 | (local_address, remote_address)) in addr_pairs_info: |
| 477 | sock = None |
| 478 | r_addr = None |
| 479 | try: |
| 480 | sock = socket.socket( |
| 481 | family=family, type=socket.SOCK_DGRAM, proto=proto) |
| 482 | sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) |
| 483 | sock.setblocking(False) |
| 484 | |
| 485 | if local_addr: |
| 486 | sock.bind(local_address) |
| 487 | if remote_addr: |
| 488 | yield from self.sock_connect(sock, remote_address) |
| 489 | r_addr = remote_address |
| 490 | except OSError as exc: |
| 491 | if sock is not None: |
| 492 | sock.close() |
| 493 | exceptions.append(exc) |
| 494 | else: |
| 495 | break |
| 496 | else: |
| 497 | raise exceptions[0] |
| 498 | |
| 499 | protocol = protocol_factory() |
| 500 | transport = self._make_datagram_transport(sock, protocol, r_addr) |
| 501 | return transport, protocol |
| 502 | |
| 503 | @tasks.coroutine |
| 504 | def create_server(self, protocol_factory, host=None, port=None, |
| 505 | *, |
| 506 | family=socket.AF_UNSPEC, |
| 507 | flags=socket.AI_PASSIVE, |
| 508 | sock=None, |
| 509 | backlog=100, |
| 510 | ssl=None, |
| 511 | reuse_address=None): |
| 512 | """XXX""" |
Guido van Rossum | 28dff0d | 2013-11-01 14:22:30 -0700 | [diff] [blame] | 513 | if isinstance(ssl, bool): |
| 514 | raise TypeError('ssl argument must be an SSLContext or None') |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 515 | if host is not None or port is not None: |
| 516 | if sock is not None: |
| 517 | raise ValueError( |
| 518 | 'host/port and sock can not be specified at the same time') |
| 519 | |
| 520 | AF_INET6 = getattr(socket, 'AF_INET6', 0) |
| 521 | if reuse_address is None: |
| 522 | reuse_address = os.name == 'posix' and sys.platform != 'cygwin' |
| 523 | sockets = [] |
| 524 | if host == '': |
| 525 | host = None |
| 526 | |
| 527 | infos = yield from self.getaddrinfo( |
| 528 | host, port, family=family, |
| 529 | type=socket.SOCK_STREAM, proto=0, flags=flags) |
| 530 | if not infos: |
| 531 | raise OSError('getaddrinfo() returned empty list') |
| 532 | |
| 533 | completed = False |
| 534 | try: |
| 535 | for res in infos: |
| 536 | af, socktype, proto, canonname, sa = res |
Guido van Rossum | 32e4685 | 2013-10-19 17:04:25 -0700 | [diff] [blame] | 537 | try: |
| 538 | sock = socket.socket(af, socktype, proto) |
| 539 | except socket.error: |
| 540 | # Assume it's a bad family/type/protocol combination. |
| 541 | continue |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 542 | sockets.append(sock) |
| 543 | if reuse_address: |
| 544 | sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, |
| 545 | True) |
| 546 | # Disable IPv4/IPv6 dual stack support (enabled by |
| 547 | # default on Linux) which makes a single socket |
| 548 | # listen on both address families. |
| 549 | if af == AF_INET6 and hasattr(socket, 'IPPROTO_IPV6'): |
| 550 | sock.setsockopt(socket.IPPROTO_IPV6, |
| 551 | socket.IPV6_V6ONLY, |
| 552 | True) |
| 553 | try: |
| 554 | sock.bind(sa) |
| 555 | except OSError as err: |
| 556 | raise OSError(err.errno, 'error while attempting ' |
| 557 | 'to bind on address %r: %s' |
| 558 | % (sa, err.strerror.lower())) |
| 559 | completed = True |
| 560 | finally: |
| 561 | if not completed: |
| 562 | for sock in sockets: |
| 563 | sock.close() |
| 564 | else: |
| 565 | if sock is None: |
| 566 | raise ValueError( |
| 567 | 'host and port was not specified and no sock specified') |
| 568 | sockets = [sock] |
| 569 | |
| 570 | server = Server(self, sockets) |
| 571 | for sock in sockets: |
| 572 | sock.listen(backlog) |
| 573 | sock.setblocking(False) |
| 574 | self._start_serving(protocol_factory, sock, ssl, server) |
| 575 | return server |
| 576 | |
| 577 | @tasks.coroutine |
| 578 | def connect_read_pipe(self, protocol_factory, pipe): |
| 579 | protocol = protocol_factory() |
| 580 | waiter = futures.Future(loop=self) |
| 581 | transport = self._make_read_pipe_transport(pipe, protocol, waiter) |
| 582 | yield from waiter |
| 583 | return transport, protocol |
| 584 | |
| 585 | @tasks.coroutine |
| 586 | def connect_write_pipe(self, protocol_factory, pipe): |
| 587 | protocol = protocol_factory() |
| 588 | waiter = futures.Future(loop=self) |
| 589 | transport = self._make_write_pipe_transport(pipe, protocol, waiter) |
| 590 | yield from waiter |
| 591 | return transport, protocol |
| 592 | |
| 593 | @tasks.coroutine |
| 594 | def subprocess_shell(self, protocol_factory, cmd, *, stdin=subprocess.PIPE, |
| 595 | stdout=subprocess.PIPE, stderr=subprocess.PIPE, |
| 596 | universal_newlines=False, shell=True, bufsize=0, |
| 597 | **kwargs): |
Victor Stinner | 20e0743 | 2014-02-11 11:44:56 +0100 | [diff] [blame] | 598 | if not isinstance(cmd, (bytes, str)): |
Victor Stinner | e623a12 | 2014-01-29 14:35:15 -0800 | [diff] [blame] | 599 | raise ValueError("cmd must be a string") |
| 600 | if universal_newlines: |
| 601 | raise ValueError("universal_newlines must be False") |
| 602 | if not shell: |
Victor Stinner | 323748e | 2014-01-31 12:28:30 +0100 | [diff] [blame] | 603 | raise ValueError("shell must be True") |
Victor Stinner | e623a12 | 2014-01-29 14:35:15 -0800 | [diff] [blame] | 604 | if bufsize != 0: |
| 605 | raise ValueError("bufsize must be 0") |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 606 | protocol = protocol_factory() |
| 607 | transport = yield from self._make_subprocess_transport( |
| 608 | protocol, cmd, True, stdin, stdout, stderr, bufsize, **kwargs) |
| 609 | return transport, protocol |
| 610 | |
| 611 | @tasks.coroutine |
Yury Selivanov | 5779752 | 2014-02-18 22:56:15 -0500 | [diff] [blame] | 612 | def subprocess_exec(self, protocol_factory, program, *args, |
| 613 | stdin=subprocess.PIPE, stdout=subprocess.PIPE, |
| 614 | stderr=subprocess.PIPE, universal_newlines=False, |
| 615 | shell=False, bufsize=0, **kwargs): |
Victor Stinner | e623a12 | 2014-01-29 14:35:15 -0800 | [diff] [blame] | 616 | if universal_newlines: |
| 617 | raise ValueError("universal_newlines must be False") |
| 618 | if shell: |
| 619 | raise ValueError("shell must be False") |
| 620 | if bufsize != 0: |
| 621 | raise ValueError("bufsize must be 0") |
Victor Stinner | 20e0743 | 2014-02-11 11:44:56 +0100 | [diff] [blame] | 622 | popen_args = (program,) + args |
| 623 | for arg in popen_args: |
| 624 | if not isinstance(arg, (str, bytes)): |
| 625 | raise TypeError("program arguments must be " |
| 626 | "a bytes or text string, not %s" |
| 627 | % type(arg).__name__) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 628 | protocol = protocol_factory() |
| 629 | transport = yield from self._make_subprocess_transport( |
Yury Selivanov | 5779752 | 2014-02-18 22:56:15 -0500 | [diff] [blame] | 630 | protocol, popen_args, False, stdin, stdout, stderr, |
| 631 | bufsize, **kwargs) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 632 | return transport, protocol |
| 633 | |
Yury Selivanov | 569efa2 | 2014-02-18 18:02:19 -0500 | [diff] [blame] | 634 | def set_exception_handler(self, handler): |
| 635 | """Set handler as the new event loop exception handler. |
| 636 | |
| 637 | If handler is None, the default exception handler will |
| 638 | be set. |
| 639 | |
| 640 | If handler is a callable object, it should have a |
| 641 | matching signature to '(loop, context)', where 'loop' |
| 642 | will be a reference to the active event loop, 'context' |
| 643 | will be a dict object (see `call_exception_handler()` |
| 644 | documentation for details about context). |
| 645 | """ |
| 646 | if handler is not None and not callable(handler): |
| 647 | raise TypeError('A callable object or None is expected, ' |
| 648 | 'got {!r}'.format(handler)) |
| 649 | self._exception_handler = handler |
| 650 | |
| 651 | def default_exception_handler(self, context): |
| 652 | """Default exception handler. |
| 653 | |
| 654 | This is called when an exception occurs and no exception |
| 655 | handler is set, and can be called by a custom exception |
| 656 | handler that wants to defer to the default behavior. |
| 657 | |
| 658 | context parameter has the same meaning as in |
| 659 | `call_exception_handler()`. |
| 660 | """ |
| 661 | message = context.get('message') |
| 662 | if not message: |
| 663 | message = 'Unhandled exception in event loop' |
| 664 | |
| 665 | exception = context.get('exception') |
| 666 | if exception is not None: |
| 667 | exc_info = (type(exception), exception, exception.__traceback__) |
| 668 | else: |
| 669 | exc_info = False |
| 670 | |
| 671 | log_lines = [message] |
| 672 | for key in sorted(context): |
| 673 | if key in {'message', 'exception'}: |
| 674 | continue |
| 675 | log_lines.append('{}: {!r}'.format(key, context[key])) |
| 676 | |
| 677 | logger.error('\n'.join(log_lines), exc_info=exc_info) |
| 678 | |
| 679 | def call_exception_handler(self, context): |
| 680 | """Call the current event loop exception handler. |
| 681 | |
| 682 | context is a dict object containing the following keys |
| 683 | (new keys maybe introduced later): |
| 684 | - 'message': Error message; |
| 685 | - 'exception' (optional): Exception object; |
| 686 | - 'future' (optional): Future instance; |
| 687 | - 'handle' (optional): Handle instance; |
| 688 | - 'protocol' (optional): Protocol instance; |
| 689 | - 'transport' (optional): Transport instance; |
| 690 | - 'socket' (optional): Socket instance. |
| 691 | |
| 692 | Note: this method should not be overloaded in subclassed |
| 693 | event loops. For any custom exception handling, use |
| 694 | `set_exception_handler()` method. |
| 695 | """ |
| 696 | if self._exception_handler is None: |
| 697 | try: |
| 698 | self.default_exception_handler(context) |
| 699 | except Exception: |
| 700 | # Second protection layer for unexpected errors |
| 701 | # in the default implementation, as well as for subclassed |
| 702 | # event loops with overloaded "default_exception_handler". |
| 703 | logger.error('Exception in default exception handler', |
| 704 | exc_info=True) |
| 705 | else: |
| 706 | try: |
| 707 | self._exception_handler(self, context) |
| 708 | except Exception as exc: |
| 709 | # Exception in the user set custom exception handler. |
| 710 | try: |
| 711 | # Let's try default handler. |
| 712 | self.default_exception_handler({ |
| 713 | 'message': 'Unhandled error in exception handler', |
| 714 | 'exception': exc, |
| 715 | 'context': context, |
| 716 | }) |
| 717 | except Exception: |
| 718 | # Guard 'default_exception_handler' in case it's |
| 719 | # overloaded. |
| 720 | logger.error('Exception in default exception handler ' |
| 721 | 'while handling an unexpected error ' |
| 722 | 'in custom exception handler', |
| 723 | exc_info=True) |
| 724 | |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 725 | def _add_callback(self, handle): |
| 726 | """Add a Handle to ready or scheduled.""" |
| 727 | assert isinstance(handle, events.Handle), 'A Handle is required here' |
| 728 | if handle._cancelled: |
| 729 | return |
| 730 | if isinstance(handle, events.TimerHandle): |
| 731 | heapq.heappush(self._scheduled, handle) |
| 732 | else: |
| 733 | self._ready.append(handle) |
| 734 | |
| 735 | def _add_callback_signalsafe(self, handle): |
| 736 | """Like _add_callback() but called from a signal handler.""" |
| 737 | self._add_callback(handle) |
| 738 | self._write_to_self() |
| 739 | |
| 740 | def _run_once(self): |
| 741 | """Run one full iteration of the event loop. |
| 742 | |
| 743 | This calls all currently ready callbacks, polls for I/O, |
| 744 | schedules the resulting callbacks, and finally schedules |
| 745 | 'call_later' callbacks. |
| 746 | """ |
| 747 | # Remove delayed calls that were cancelled from head of queue. |
| 748 | while self._scheduled and self._scheduled[0]._cancelled: |
| 749 | heapq.heappop(self._scheduled) |
| 750 | |
| 751 | timeout = None |
| 752 | if self._ready: |
| 753 | timeout = 0 |
| 754 | elif self._scheduled: |
| 755 | # Compute the desired timeout. |
| 756 | when = self._scheduled[0]._when |
| 757 | deadline = max(0, when - self.time()) |
| 758 | if timeout is None: |
| 759 | timeout = deadline |
| 760 | else: |
| 761 | timeout = min(timeout, deadline) |
| 762 | |
| 763 | # TODO: Instrumentation only in debug mode? |
Victor Stinner | 49d0f4e | 2014-01-31 12:59:43 +0100 | [diff] [blame] | 764 | if logger.isEnabledFor(logging.INFO): |
Victor Stinner | 22463aa | 2014-01-20 23:56:40 +0100 | [diff] [blame] | 765 | t0 = self.time() |
| 766 | event_list = self._selector.select(timeout) |
| 767 | t1 = self.time() |
Victor Stinner | 22463aa | 2014-01-20 23:56:40 +0100 | [diff] [blame] | 768 | if t1-t0 >= 1: |
| 769 | level = logging.INFO |
| 770 | else: |
| 771 | level = logging.DEBUG |
Victor Stinner | 4a2dbeb | 2014-01-22 12:26:01 +0100 | [diff] [blame] | 772 | if timeout is not None: |
| 773 | logger.log(level, 'poll %.3f took %.3f seconds', |
| 774 | timeout, t1-t0) |
| 775 | else: |
| 776 | logger.log(level, 'poll took %.3f seconds', t1-t0) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 777 | else: |
Victor Stinner | 22463aa | 2014-01-20 23:56:40 +0100 | [diff] [blame] | 778 | event_list = self._selector.select(timeout) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 779 | self._process_events(event_list) |
| 780 | |
| 781 | # Handle 'later' callbacks that are ready. |
Victor Stinner | ed1654f | 2014-02-10 23:42:32 +0100 | [diff] [blame] | 782 | end_time = self.time() + self._clock_resolution |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 783 | while self._scheduled: |
| 784 | handle = self._scheduled[0] |
Victor Stinner | ed1654f | 2014-02-10 23:42:32 +0100 | [diff] [blame] | 785 | if handle._when >= end_time: |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 786 | break |
| 787 | handle = heapq.heappop(self._scheduled) |
| 788 | self._ready.append(handle) |
| 789 | |
| 790 | # This is the only place where callbacks are actually *called*. |
| 791 | # All other places just add them to ready. |
| 792 | # Note: We run all currently scheduled callbacks, but not any |
| 793 | # callbacks scheduled by callbacks run this time around -- |
| 794 | # they will be run the next time (after another I/O poll). |
| 795 | # Use an idiom that is threadsafe without using locks. |
| 796 | ntodo = len(self._ready) |
| 797 | for i in range(ntodo): |
| 798 | handle = self._ready.popleft() |
| 799 | if not handle._cancelled: |
| 800 | handle._run() |
| 801 | handle = None # Needed to break cycles when an exception occurs. |
Victor Stinner | 0f3e6bc | 2014-02-19 23:15:02 +0100 | [diff] [blame] | 802 | |
| 803 | def get_debug(self): |
| 804 | return self._debug |
| 805 | |
| 806 | def set_debug(self, enabled): |
| 807 | self._debug = enabled |