/usr/lib/python3/dist-packages/aiohttp/streams.py is in python3-aiohttp 0.20.2-1.
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 | import sys
import asyncio
import collections
import functools
import traceback
from .log import internal_logger
__all__ = (
'EofStream', 'StreamReader', 'DataQueue', 'ChunksQueue',
'FlowControlStreamReader',
'FlowControlDataQueue', 'FlowControlChunksQueue')
PY_35 = sys.version_info >= (3, 5)
EOF_MARKER = b''
DEFAULT_LIMIT = 2 ** 16
class EofStream(Exception):
"""eof stream indication."""
class AsyncStreamIterator:
def __init__(self, read_func):
self.read_func = read_func
@asyncio.coroutine
def __aiter__(self):
return self
@asyncio.coroutine
def __anext__(self):
try:
rv = yield from self.read_func()
except EofStream:
raise StopAsyncIteration # NOQA
if rv == EOF_MARKER:
raise StopAsyncIteration # NOQA
return rv
class AsyncStreamReaderMixin:
if PY_35:
@asyncio.coroutine
def __aiter__(self):
return AsyncStreamIterator(self.readline)
def iter_chunked(self, n):
"""Returns an asynchronous iterator that yields chunks of size n.
.. versionadded:: Python-3.5 available for Python 3.5+ only
"""
return AsyncStreamIterator(lambda: self.read(n))
def iter_any(self):
"""Returns an asynchronous iterator that yields slices of data as they come.
.. versionadded:: Python-3.5 available for Python 3.5+ only
"""
return AsyncStreamIterator(self.readany)
class StreamReader(asyncio.StreamReader, AsyncStreamReaderMixin):
"""An enhancement of :class:`asyncio.StreamReader`.
Supports asynchronous iteration by line, chunk or as available::
async for line in reader:
...
async for chunk in reader.iter_chunked(1024):
...
async for slice in reader.iter_any():
...
.. automethod:: AsyncStreamReaderMixin.iter_chunked
.. automethod:: AsyncStreamReaderMixin.iter_any
"""
total_bytes = 0
def __init__(self, limit=DEFAULT_LIMIT, loop=None):
self._limit = limit
if loop is None:
loop = asyncio.get_event_loop()
self._loop = loop
self._buffer = collections.deque()
self._buffer_size = 0
self._buffer_offset = 0
self._eof = False
self._waiter = None
self._eof_waiter = None
self._exception = None
def __repr__(self):
info = ['StreamReader']
if self._buffer_size:
info.append('%d bytes' % self._buffer_size)
if self._eof:
info.append('eof')
if self._limit != DEFAULT_LIMIT:
info.append('l=%d' % self._limit)
if self._waiter:
info.append('w=%r' % self._waiter)
if self._exception:
info.append('e=%r' % self._exception)
return '<%s>' % ' '.join(info)
def exception(self):
return self._exception
def set_exception(self, exc):
self._exception = exc
waiter = self._waiter
if waiter is not None:
self._waiter = None
if not waiter.cancelled():
waiter.set_exception(exc)
def feed_eof(self):
self._eof = True
waiter = self._waiter
if waiter is not None:
self._waiter = None
if not waiter.cancelled():
waiter.set_result(True)
waiter = self._eof_waiter
if waiter is not None:
self._eof_waiter = None
if not waiter.cancelled():
waiter.set_result(True)
def is_eof(self):
"""Return True if 'feed_eof' was called."""
return self._eof
def at_eof(self):
"""Return True if the buffer is empty and 'feed_eof' was called."""
return self._eof and not self._buffer
@asyncio.coroutine
def wait_eof(self):
if self._eof:
return
assert self._eof_waiter is None
self._eof_waiter = asyncio.Future(loop=self._loop)
try:
yield from self._eof_waiter
finally:
self._eof_waiter = None
def feed_data(self, data):
assert not self._eof, 'feed_data after feed_eof'
if not data:
return
self._buffer.append(data)
self._buffer_size += len(data)
self.total_bytes += len(data)
waiter = self._waiter
if waiter is not None:
self._waiter = None
if not waiter.cancelled():
waiter.set_result(False)
def _create_waiter(self, func_name):
# StreamReader uses a future to link the protocol feed_data() method
# to a read coroutine. Running two read coroutines at the same time
# would have an unexpected behaviour. It would not possible to know
# which coroutine would get the next data.
if self._waiter is not None:
raise RuntimeError('%s() called while another coroutine is '
'already waiting for incoming data' % func_name)
return asyncio.Future(loop=self._loop)
@asyncio.coroutine
def readline(self):
if self._exception is not None:
raise self._exception
line = []
line_size = 0
not_enough = True
while not_enough:
while self._buffer and not_enough:
offset = self._buffer_offset
ichar = self._buffer[0].find(b'\n', offset) + 1
# Read from current offset to found b'\n' or to the end.
data = self._read_nowait(ichar - offset if ichar else 0)
line.append(data)
line_size += len(data)
if ichar:
not_enough = False
if line_size > self._limit:
raise ValueError('Line is too long')
if self._eof:
break
if not_enough:
self._waiter = self._create_waiter('readline')
try:
yield from self._waiter
finally:
self._waiter = None
return b''.join(line)
@asyncio.coroutine
def read(self, n=-1):
if self._exception is not None:
raise self._exception
# migration problem; with DataQueue you have to catch
# EofStream exception, so common way is to run payload.read() inside
# infinite loop. what can cause real infinite loop with StreamReader
# lets keep this code one major release.
if __debug__:
if self._eof and not self._buffer:
self._eof_counter = getattr(self, '_eof_counter', 0) + 1
if self._eof_counter > 5:
stack = traceback.format_stack()
internal_logger.warning(
'Multiple access to StreamReader in eof state, '
'might be infinite loop: \n%s', stack)
if not n:
return EOF_MARKER
if n < 0:
# This used to just loop creating a new waiter hoping to
# collect everything in self._buffer, but that would
# deadlock if the subprocess sends more than self.limit
# bytes. So just call self.readany() until EOF.
blocks = []
while True:
block = yield from self.readany()
if not block:
break
blocks.append(block)
return b''.join(blocks)
if not self._buffer and not self._eof:
self._waiter = self._create_waiter('read')
try:
yield from self._waiter
finally:
self._waiter = None
return self._read_nowait(n)
@asyncio.coroutine
def readany(self):
if self._exception is not None:
raise self._exception
if not self._buffer and not self._eof:
self._waiter = self._create_waiter('readany')
try:
yield from self._waiter
finally:
self._waiter = None
return self._read_nowait()
@asyncio.coroutine
def readexactly(self, n):
if self._exception is not None:
raise self._exception
# There used to be "optimized" code here. It created its own
# Future and waited until self._buffer had at least the n
# bytes, then called read(n). Unfortunately, this could pause
# the transport if the argument was larger than the pause
# limit (which is twice self._limit). So now we just read()
# into a local buffer.
blocks = []
while n > 0:
block = yield from self.read(n)
if not block:
partial = b''.join(blocks)
raise asyncio.streams.IncompleteReadError(
partial, len(partial) + n)
blocks.append(block)
n -= len(block)
return b''.join(blocks)
def read_nowait(self, n=None):
if self._exception is not None:
raise self._exception
if self._waiter and not self._waiter.done():
raise RuntimeError(
'Called while some coroutine is waiting for incoming data.')
return self._read_nowait(n)
def _read_nowait(self, n=None):
if not self._buffer:
return EOF_MARKER
first_buffer = self._buffer[0]
offset = self._buffer_offset
if n and len(first_buffer) - offset > n:
data = first_buffer[offset:offset + n]
self._buffer_offset += n
elif offset:
self._buffer.popleft()
data = first_buffer[offset:]
self._buffer_offset = 0
else:
data = self._buffer.popleft()
self._buffer_size -= len(data)
return data
class EmptyStreamReader(AsyncStreamReaderMixin):
def exception(self):
return None
def set_exception(self, exc):
pass
def feed_eof(self):
pass
def is_eof(self):
return True
def at_eof(self):
return True
@asyncio.coroutine
def wait_eof(self):
return
def feed_data(self, data):
pass
@asyncio.coroutine
def readline(self):
return EOF_MARKER
@asyncio.coroutine
def read(self, n=-1):
return EOF_MARKER
@asyncio.coroutine
def readany(self):
return EOF_MARKER
@asyncio.coroutine
def readexactly(self, n):
raise asyncio.streams.IncompleteReadError(b'', n)
def read_nowait(self):
return EOF_MARKER
class DataQueue:
"""DataQueue is a general-purpose blocking queue with one reader."""
def __init__(self, *, loop=None):
self._loop = loop
self._eof = False
self._waiter = None
self._exception = None
self._size = 0
self._buffer = collections.deque()
def is_eof(self):
return self._eof
def at_eof(self):
return self._eof and not self._buffer
def exception(self):
return self._exception
def set_exception(self, exc):
self._exception = exc
waiter = self._waiter
if waiter is not None:
self._waiter = None
if not waiter.done():
waiter.set_exception(exc)
def feed_data(self, data, size=0):
self._size += size
self._buffer.append((data, size))
waiter = self._waiter
if waiter is not None:
self._waiter = None
if not waiter.cancelled():
waiter.set_result(True)
def feed_eof(self):
self._eof = True
waiter = self._waiter
if waiter is not None:
self._waiter = None
if not waiter.cancelled():
waiter.set_result(False)
@asyncio.coroutine
def read(self):
if not self._buffer and not self._eof:
if self._exception is not None:
raise self._exception
assert not self._waiter
self._waiter = asyncio.Future(loop=self._loop)
try:
yield from self._waiter
except (asyncio.CancelledError, asyncio.TimeoutError):
self._waiter = None
raise
if self._buffer:
data, size = self._buffer.popleft()
self._size -= size
return data
else:
if self._exception is not None:
raise self._exception
else:
raise EofStream
if PY_35:
@asyncio.coroutine
def __aiter__(self):
return AsyncStreamIterator(self.read)
class ChunksQueue(DataQueue):
"""Like a :class:`DataQueue`, but for binary chunked data transfer."""
@asyncio.coroutine
def read(self):
try:
return (yield from super().read())
except EofStream:
return EOF_MARKER
readany = read
def maybe_resume(func):
@asyncio.coroutine
@functools.wraps(func)
def wrapper(self, *args, **kw):
result = yield from func(self, *args, **kw)
if self._stream.paused:
if self._buffer_size < self._b_limit:
try:
self._stream.transport.resume_reading()
except (AttributeError, NotImplementedError):
pass
else:
self._stream.paused = False
else:
if self._buffer_size > self._b_limit:
try:
self._stream.transport.pause_reading()
except (AttributeError, NotImplementedError):
pass
else:
self._stream.paused = True
return result
return wrapper
class FlowControlStreamReader(StreamReader):
def __init__(self, stream, limit=DEFAULT_LIMIT, *args, **kwargs):
super().__init__(*args, **kwargs)
self._stream = stream
self._b_limit = limit * 2
# resume transport reading
if stream.paused:
try:
self._stream.transport.resume_reading()
except (AttributeError, NotImplementedError):
pass
def feed_data(self, data, size=0):
has_waiter = self._waiter is not None and not self._waiter.cancelled()
super().feed_data(data)
if (not self._stream.paused and
not has_waiter and self._buffer_size > self._b_limit):
try:
self._stream.transport.pause_reading()
except (AttributeError, NotImplementedError):
pass
else:
self._stream.paused = True
@maybe_resume
def read(self, n=-1):
return (yield from super().read(n))
@maybe_resume
def readline(self):
return (yield from super().readline())
@maybe_resume
def readany(self):
return (yield from super().readany())
@maybe_resume
def readexactly(self, n):
return (yield from super().readexactly(n))
class FlowControlDataQueue(DataQueue):
"""FlowControlDataQueue resumes and pauses an underlying stream.
It is a destination for parsed data."""
def __init__(self, stream, *, limit=DEFAULT_LIMIT, loop=None):
super().__init__(loop=loop)
self._stream = stream
self._limit = limit * 2
# resume transport reading
if stream.paused:
try:
self._stream.transport.resume_reading()
except (AttributeError, NotImplementedError):
pass
else:
self._stream.paused = False
def feed_data(self, data, size):
has_waiter = self._waiter is not None and not self._waiter.cancelled()
super().feed_data(data, size)
if (not self._stream.paused and
not has_waiter and self._size > self._limit):
try:
self._stream.transport.pause_reading()
except (AttributeError, NotImplementedError):
pass
else:
self._stream.paused = True
@asyncio.coroutine
def read(self):
result = yield from super().read()
if self._stream.paused:
if self._size < self._limit:
try:
self._stream.transport.resume_reading()
except (AttributeError, NotImplementedError):
pass
else:
self._stream.paused = False
else:
if self._size > self._limit:
try:
self._stream.transport.pause_reading()
except (AttributeError, NotImplementedError):
pass
else:
self._stream.paused = True
return result
class FlowControlChunksQueue(FlowControlDataQueue):
@asyncio.coroutine
def read(self):
try:
return (yield from super().read())
except EofStream:
return EOF_MARKER
readany = read
|