/usr/lib/python2.7/dist-packages/pika/adapters/base_connection.py is in python-pika 0.10.0-1.
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 | """Base class extended by connection adapters. This extends the
connection.Connection class to encapsulate connection behavior but still
isolate socket and low level communication.
"""
import errno
import logging
import socket
import ssl
import pika.compat
from pika import connection
from pika import exceptions
try:
SOL_TCP = socket.SOL_TCP
except AttributeError:
SOL_TCP = 6
if pika.compat.PY2:
_SOCKET_ERROR = socket.error
else:
# socket.error was deprecated and replaced by OSError in python 3.3
_SOCKET_ERROR = OSError
LOGGER = logging.getLogger(__name__)
class BaseConnection(connection.Connection):
"""BaseConnection class that should be extended by connection adapters"""
# Use epoll's constants to keep life easy
READ = 0x0001
WRITE = 0x0004
ERROR = 0x0008
ERRORS_TO_ABORT = [errno.EBADF, errno.ECONNABORTED, errno.EPIPE]
ERRORS_TO_IGNORE = [errno.EWOULDBLOCK, errno.EAGAIN, errno.EINTR]
DO_HANDSHAKE = True
WARN_ABOUT_IOLOOP = False
def __init__(self,
parameters=None,
on_open_callback=None,
on_open_error_callback=None,
on_close_callback=None,
ioloop=None,
stop_ioloop_on_close=True):
"""Create a new instance of the Connection object.
:param pika.connection.Parameters parameters: Connection parameters
:param method on_open_callback: Method to call on connection open
:param on_open_error_callback: Method to call if the connection cant
be opened
:type on_open_error_callback: method
:param method on_close_callback: Method to call on connection close
:param object ioloop: IOLoop object to use
:param bool stop_ioloop_on_close: Call ioloop.stop() if disconnected
:raises: RuntimeError
:raises: ValueError
"""
if parameters and not isinstance(parameters, connection.Parameters):
raise ValueError('Expected instance of Parameters, not %r' %
parameters)
# Let the developer know we could not import SSL
if parameters and parameters.ssl and not ssl:
raise RuntimeError("SSL specified but it is not available")
self.base_events = self.READ | self.ERROR
self.event_state = self.base_events
self.ioloop = ioloop
self.socket = None
self.stop_ioloop_on_close = stop_ioloop_on_close
self.write_buffer = None
super(BaseConnection, self).__init__(parameters, on_open_callback,
on_open_error_callback,
on_close_callback)
def add_timeout(self, deadline, callback_method):
"""Add the callback_method to the IOLoop timer to fire after deadline
seconds. Returns a handle to the timeout
:param int deadline: The number of seconds to wait to call callback
:param method callback_method: The callback method
:rtype: str
"""
return self.ioloop.add_timeout(deadline, callback_method)
def close(self, reply_code=200, reply_text='Normal shutdown'):
"""Disconnect from RabbitMQ. If there are any open channels, it will
attempt to close them prior to fully disconnecting. Channels which
have active consumers will attempt to send a Basic.Cancel to RabbitMQ
to cleanly stop the delivery of messages prior to closing the channel.
:param int reply_code: The code number for the close
:param str reply_text: The text reason for the close
"""
super(BaseConnection, self).close(reply_code, reply_text)
self._handle_ioloop_stop()
def remove_timeout(self, timeout_id):
"""Remove the timeout from the IOLoop by the ID returned from
add_timeout.
:rtype: str
"""
self.ioloop.remove_timeout(timeout_id)
def _adapter_connect(self):
"""Connect to the RabbitMQ broker, returning True if connected.
:returns: error string or exception instance on error; None on success
"""
# Get the addresses for the socket, supporting IPv4 & IPv6
while True:
try:
addresses = socket.getaddrinfo(self.params.host, self.params.port,
0, socket.SOCK_STREAM,
socket.IPPROTO_TCP)
break
except _SOCKET_ERROR as error:
if error.errno == errno.EINTR:
continue
LOGGER.critical('Could not get addresses to use: %s (%s)', error,
self.params.host)
return error
# If the socket is created and connected, continue on
error = "No socket addresses available"
for sock_addr in addresses:
error = self._create_and_connect_to_socket(sock_addr)
if not error:
# Make the socket non-blocking after the connect
self.socket.setblocking(0)
return None
self._cleanup_socket()
# Failed to connect
return error
def _adapter_disconnect(self):
"""Invoked if the connection is being told to disconnect"""
try:
self._remove_heartbeat()
self._cleanup_socket()
self._check_state_on_disconnect()
finally:
# Ensure proper cleanup since _check_state_on_disconnect may raise
# an exception
self._handle_ioloop_stop()
self._init_connection_state()
def _check_state_on_disconnect(self):
"""Checks to see if we were in opening a connection with RabbitMQ when
we were disconnected and raises exceptions for the anticipated
exception types.
"""
if self.connection_state == self.CONNECTION_PROTOCOL:
LOGGER.error('Incompatible Protocol Versions')
raise exceptions.IncompatibleProtocolError
elif self.connection_state == self.CONNECTION_START:
LOGGER.error("Socket closed while authenticating indicating a "
"probable authentication error")
raise exceptions.ProbableAuthenticationError
elif self.connection_state == self.CONNECTION_TUNE:
LOGGER.error("Socket closed while tuning the connection indicating "
"a probable permission error when accessing a virtual "
"host")
raise exceptions.ProbableAccessDeniedError
elif self.is_open:
LOGGER.warning("Socket closed when connection was open")
elif not self.is_closed and not self.is_closing:
LOGGER.warning('Unknown state on disconnect: %i',
self.connection_state)
def _cleanup_socket(self):
"""Close the socket cleanly"""
if self.socket:
try:
self.socket.shutdown(socket.SHUT_RDWR)
except _SOCKET_ERROR:
pass
self.socket.close()
self.socket = None
def _create_and_connect_to_socket(self, sock_addr_tuple):
"""Create socket and connect to it, using SSL if enabled.
:returns: error string on failure; None on success
"""
self.socket = socket.socket(sock_addr_tuple[0], socket.SOCK_STREAM, 0)
self.socket.setsockopt(SOL_TCP, socket.TCP_NODELAY, 1)
self.socket.settimeout(self.params.socket_timeout)
# Wrap socket if using SSL
if self.params.ssl:
self.socket = self._wrap_socket(self.socket)
ssl_text = " with SSL"
else:
ssl_text = ""
LOGGER.info('Connecting to %s:%s%s', sock_addr_tuple[4][0],
sock_addr_tuple[4][1], ssl_text)
# Connect to the socket
try:
self.socket.connect(sock_addr_tuple[4])
except socket.timeout:
error = 'Connection to %s:%s failed: timeout' % (
sock_addr_tuple[4][0], sock_addr_tuple[4][1]
)
LOGGER.error(error)
return error
except _SOCKET_ERROR as error:
error = 'Connection to %s:%s failed: %s' % (sock_addr_tuple[4][0],
sock_addr_tuple[4][1],
error)
LOGGER.warning(error)
return error
# Handle SSL Connection Negotiation
if self.params.ssl and self.DO_HANDSHAKE:
try:
self._do_ssl_handshake()
except ssl.SSLError as error:
error = 'SSL connection to %s:%s failed: %s' % (
sock_addr_tuple[4][0], sock_addr_tuple[4][1], error
)
LOGGER.error(error)
return error
# Made it this far
return None
def _do_ssl_handshake(self):
"""Perform SSL handshaking, copied from python stdlib test_ssl.py.
"""
if not self.DO_HANDSHAKE:
return
while True:
try:
self.socket.do_handshake()
break
except ssl.SSLError as err:
if err.args[0] == ssl.SSL_ERROR_WANT_READ:
self.event_state = self.READ
elif err.args[0] == ssl.SSL_ERROR_WANT_WRITE:
self.event_state = self.WRITE
else:
raise
self._manage_event_state()
@staticmethod
def _get_error_code(error_value):
"""Get the error code from the error_value accounting for Python
version differences.
:rtype: int
"""
if not error_value:
return None
if hasattr(error_value, 'errno'): # Python >= 2.6
return error_value.errno
elif error_value is not None:
return error_value[0] # Python <= 2.5
return None
def _flush_outbound(self):
"""write early, if the socket will take the data why not get it out
there asap.
"""
self._handle_write()
self._manage_event_state()
def _handle_disconnect(self):
"""Called internally when the socket is disconnected already
"""
self._adapter_disconnect()
self._on_connection_closed(None, True)
def _handle_ioloop_stop(self):
"""Invoked when the connection is closed to determine if the IOLoop
should be stopped or not.
"""
if self.stop_ioloop_on_close and self.ioloop:
self.ioloop.stop()
elif self.WARN_ABOUT_IOLOOP:
LOGGER.warning('Connection is closed but not stopping IOLoop')
def _handle_error(self, error_value):
"""Internal error handling method. Here we expect a socket.error
coming in and will handle different socket errors differently.
:param int|object error_value: The inbound error
"""
if 'timed out' in str(error_value):
raise socket.timeout
error_code = self._get_error_code(error_value)
if not error_code:
LOGGER.critical("Tried to handle an error where no error existed")
return
# Ok errors, just continue what we were doing before
if error_code in self.ERRORS_TO_IGNORE:
LOGGER.debug("Ignoring %s", error_code)
return
# Socket is no longer connected, abort
elif error_code in self.ERRORS_TO_ABORT:
LOGGER.error("Fatal Socket Error: %r", error_value)
elif self.params.ssl and isinstance(error_value, ssl.SSLError):
if error_value.args[0] == ssl.SSL_ERROR_WANT_READ:
self.event_state = self.READ
elif error_value.args[0] == ssl.SSL_ERROR_WANT_WRITE:
self.event_state = self.WRITE
else:
LOGGER.error("SSL Socket error: %r", error_value)
else:
# Haven't run into this one yet, log it.
LOGGER.error("Socket Error: %s", error_code)
# Disconnect from our IOLoop and let Connection know what's up
self._handle_disconnect()
def _handle_timeout(self):
"""Handle a socket timeout in read or write.
We don't do anything in the non-blocking handlers because we
only have the socket in a blocking state during connect."""
pass
def _handle_events(self, fd, events, error=None, write_only=False):
"""Handle IO/Event loop events, processing them.
:param int fd: The file descriptor for the events
:param int events: Events from the IO/Event loop
:param int error: Was an error specified
:param bool write_only: Only handle write events
"""
if not self.socket:
LOGGER.error('Received events on closed socket: %r', fd)
return
if self.socket and (events & self.WRITE):
self._handle_write()
self._manage_event_state()
if self.socket and not write_only and (events & self.READ):
self._handle_read()
if (self.socket and write_only and (events & self.READ) and
(events & self.ERROR)):
LOGGER.error('BAD libc: Write-Only but Read+Error. '
'Assume socket disconnected.')
self._handle_disconnect()
if self.socket and (events & self.ERROR):
LOGGER.error('Error event %r, %r', events, error)
self._handle_error(error)
def _handle_read(self):
"""Read from the socket and call our on_data_available with the data."""
try:
while True:
try:
if self.params.ssl:
data = self.socket.read(self._buffer_size)
else:
data = self.socket.recv(self._buffer_size)
break
except _SOCKET_ERROR as error:
if error.errno == errno.EINTR:
continue
else:
raise
except socket.timeout:
self._handle_timeout()
return 0
except ssl.SSLError as error:
if error.args[0] == ssl.SSL_ERROR_WANT_READ:
# ssl wants more data but there is nothing currently
# available in the socket, wait for it to become readable.
return 0
return self._handle_error(error)
except _SOCKET_ERROR as error:
if error.errno in (errno.EAGAIN, errno.EWOULDBLOCK):
return 0
return self._handle_error(error)
# Empty data, should disconnect
if not data or data == 0:
LOGGER.error('Read empty data, calling disconnect')
return self._handle_disconnect()
# Pass the data into our top level frame dispatching method
self._on_data_available(data)
return len(data)
def _handle_write(self):
"""Try and write as much as we can, if we get blocked requeue
what's left"""
bytes_written = 0
try:
while self.outbound_buffer:
frame = self.outbound_buffer.popleft()
while True:
try:
bw = self.socket.send(frame)
break
except _SOCKET_ERROR as error:
if error.errno == errno.EINTR:
continue
else:
raise
bytes_written += bw
if bw < len(frame):
LOGGER.debug("Partial write, requeing remaining data")
self.outbound_buffer.appendleft(frame[bw:])
break
except socket.timeout:
# Will only come here if the socket is blocking
LOGGER.debug("socket timeout, requeuing frame")
self.outbound_buffer.appendleft(frame)
self._handle_timeout()
except _SOCKET_ERROR as error:
if error.errno in (errno.EAGAIN, errno.EWOULDBLOCK):
LOGGER.debug("Would block, requeuing frame")
self.outbound_buffer.appendleft(frame)
else:
return self._handle_error(error)
return bytes_written
def _init_connection_state(self):
"""Initialize or reset all of our internal state variables for a given
connection. If we disconnect and reconnect, all of our state needs to
be wiped.
"""
super(BaseConnection, self)._init_connection_state()
self.base_events = self.READ | self.ERROR
self.event_state = self.base_events
self.socket = None
def _manage_event_state(self):
"""Manage the bitmask for reading/writing/error which is used by the
io/event handler to specify when there is an event such as a read or
write.
"""
if self.outbound_buffer:
if not self.event_state & self.WRITE:
self.event_state |= self.WRITE
self.ioloop.update_handler(self.socket.fileno(),
self.event_state)
elif self.event_state & self.WRITE:
self.event_state = self.base_events
self.ioloop.update_handler(self.socket.fileno(), self.event_state)
def _wrap_socket(self, sock):
"""Wrap the socket for connecting over SSL.
:rtype: ssl.SSLSocket
"""
return ssl.wrap_socket(sock,
do_handshake_on_connect=self.DO_HANDSHAKE,
**self.params.ssl_options)
|