/usr/lib/python2.7/dist-packages/amqp/serialization.py is in python-amqp 1.3.3-1ubuntu1.
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 | """
Convert between bytestreams and higher-level AMQP types.
2007-11-05 Barry Pederson <bp@barryp.org>
"""
# Copyright (C) 2007 Barry Pederson <bp@barryp.org>
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
from __future__ import absolute_import
import sys
from datetime import datetime
from decimal import Decimal
from struct import pack, unpack
from time import mktime
from .exceptions import FrameSyntaxError
from .five import int_types, long_t, string, string_t, items
IS_PY3K = sys.version_info[0] >= 3
if IS_PY3K:
def byte(n):
return bytes([n])
else:
byte = chr
try:
from io import BytesIO
except ImportError: # Py2.5
try:
from cStringIO import StringIO as BytesIO # noqa
except ImportError:
from StringIO import StringIO as BytesIO # noqa
try:
bytes
except NameError:
# Python 2.5 and lower
bytes = str
ILLEGAL_TABLE_TYPE_WITH_KEY = """\
Table type {0!r} for key {1!r} not handled by amqp. [value: {2!r}]
"""
ILLEGAL_TABLE_TYPE = """\
Table type {0!r} not handled by amqp. [value: {1!r}]
"""
class AMQPReader(object):
"""Read higher-level AMQP types from a bytestream."""
def __init__(self, source):
"""Source should be either a file-like object with a read() method, or
a plain (non-unicode) string."""
if isinstance(source, bytes):
self.input = BytesIO(source)
elif hasattr(source, 'read'):
self.input = source
else:
raise ValueError(
'AMQPReader needs a file-like object or plain string')
self.bitcount = self.bits = 0
def close(self):
self.input.close()
def read(self, n):
"""Read n bytes."""
self.bitcount = self.bits = 0
return self.input.read(n)
def read_bit(self):
"""Read a single boolean value."""
if not self.bitcount:
self.bits = ord(self.input.read(1))
self.bitcount = 8
result = (self.bits & 1) == 1
self.bits >>= 1
self.bitcount -= 1
return result
def read_octet(self):
"""Read one byte, return as an integer"""
self.bitcount = self.bits = 0
return unpack('B', self.input.read(1))[0]
def read_short(self):
"""Read an unsigned 16-bit integer"""
self.bitcount = self.bits = 0
return unpack('>H', self.input.read(2))[0]
def read_long(self):
"""Read an unsigned 32-bit integer"""
self.bitcount = self.bits = 0
return unpack('>I', self.input.read(4))[0]
def read_longlong(self):
"""Read an unsigned 64-bit integer"""
self.bitcount = self.bits = 0
return unpack('>Q', self.input.read(8))[0]
def read_float(self):
"""Read float value."""
self.bitcount = self.bits = 0
return unpack('>d', self.input.read(8))[0]
def read_shortstr(self):
"""Read a short string that's stored in up to 255 bytes.
The encoding isn't specified in the AMQP spec, so
assume it's utf-8
"""
self.bitcount = self.bits = 0
slen = unpack('B', self.input.read(1))[0]
return self.input.read(slen).decode('utf-8')
def read_longstr(self):
"""Read a string that's up to 2**32 bytes.
The encoding isn't specified in the AMQP spec, so
assume it's utf-8
"""
self.bitcount = self.bits = 0
slen = unpack('>I', self.input.read(4))[0]
return self.input.read(slen).decode('utf-8')
def read_table(self):
"""Read an AMQP table, and return as a Python dictionary."""
self.bitcount = self.bits = 0
tlen = unpack('>I', self.input.read(4))[0]
table_data = AMQPReader(self.input.read(tlen))
result = {}
while table_data.input.tell() < tlen:
name = table_data.read_shortstr()
val = table_data.read_item()
result[name] = val
return result
def read_item(self):
ftype = ord(self.input.read(1))
if ftype == 83: # 'S'
val = self.read_longstr()
elif ftype == 73: # 'I'
val = unpack('>i', self.input.read(4))[0]
elif ftype == 68: # 'D'
d = self.read_octet()
n = unpack('>i', self.input.read(4))[0]
val = Decimal(n) / Decimal(10 ** d)
elif ftype == 84: # 'T'
val = self.read_timestamp()
elif ftype == 70: # 'F'
val = self.read_table() # recurse
elif ftype == 65: # 'A'
val = self.read_array()
elif ftype == 116:
val = self.read_bit()
elif ftype == 100:
val = self.read_float()
else:
raise FrameSyntaxError(
'Unknown value in table: {0!r} ({1!r})'.format(
ftype, type(ftype)))
return val
def read_array(self):
array_length = unpack('>I', self.input.read(4))[0]
array_data = AMQPReader(self.input.read(array_length))
result = []
while array_data.input.tell() < array_length:
val = array_data.read_item()
result.append(val)
return result
def read_timestamp(self):
"""Read and AMQP timestamp, which is a 64-bit integer representing
seconds since the Unix epoch in 1-second resolution.
Return as a Python datetime.datetime object,
expressed as localtime.
"""
return datetime.fromtimestamp(self.read_longlong())
class AMQPWriter(object):
"""Convert higher-level AMQP types to bytestreams."""
def __init__(self, dest=None):
"""dest may be a file-type object (with a write() method). If None
then a BytesIO is created, and the contents can be accessed with
this class's getvalue() method."""
self.out = BytesIO() if dest is None else dest
self.bits = []
self.bitcount = 0
def _flushbits(self):
if self.bits:
out = self.out
for b in self.bits:
out.write(pack('B', b))
self.bits = []
self.bitcount = 0
def close(self):
"""Pass through if possible to any file-like destinations."""
try:
self.out.close()
except AttributeError:
pass
def flush(self):
"""Pass through if possible to any file-like destinations."""
try:
self.out.flush()
except AttributeError:
pass
def getvalue(self):
"""Get what's been encoded so far if we're working with a BytesIO."""
self._flushbits()
return self.out.getvalue()
def write(self, s):
"""Write a plain Python string with no special encoding in Python 2.x,
or bytes in Python 3.x"""
self._flushbits()
self.out.write(s)
def write_bit(self, b):
"""Write a boolean value."""
b = 1 if b else 0
shift = self.bitcount % 8
if shift == 0:
self.bits.append(0)
self.bits[-1] |= (b << shift)
self.bitcount += 1
def write_octet(self, n):
"""Write an integer as an unsigned 8-bit value."""
if n < 0 or n > 255:
raise FrameSyntaxError(
'Octet {0!r} out of range 0..255'.format(n))
self._flushbits()
self.out.write(pack('B', n))
def write_short(self, n):
"""Write an integer as an unsigned 16-bit value."""
if n < 0 or n > 65535:
raise FrameSyntaxError(
'Octet {0!r} out of range 0..65535'.format(n))
self._flushbits()
self.out.write(pack('>H', int(n)))
def write_long(self, n):
"""Write an integer as an unsigned2 32-bit value."""
if n < 0 or n >= 4294967296:
raise FrameSyntaxError(
'Octet {0!r} out of range 0..2**31-1'.format(n))
self._flushbits()
self.out.write(pack('>I', n))
def write_longlong(self, n):
"""Write an integer as an unsigned 64-bit value."""
if n < 0 or n >= 18446744073709551616:
raise FrameSyntaxError(
'Octet {0!r} out of range 0..2**64-1'.format(n))
self._flushbits()
self.out.write(pack('>Q', n))
def write_shortstr(self, s):
"""Write a string up to 255 bytes long (after any encoding).
If passed a unicode string, encode with UTF-8.
"""
self._flushbits()
if isinstance(s, string):
s = s.encode('utf-8')
if len(s) > 255:
raise FrameSyntaxError(
'Shortstring overflow ({0} > 255)'.format(len(s)))
self.write_octet(len(s))
self.out.write(s)
def write_longstr(self, s):
"""Write a string up to 2**32 bytes long after encoding.
If passed a unicode string, encode as UTF-8.
"""
self._flushbits()
if isinstance(s, string):
s = s.encode('utf-8')
self.write_long(len(s))
self.out.write(s)
def write_table(self, d):
"""Write out a Python dictionary made of up string keys, and values
that are strings, signed integers, Decimal, datetime.datetime, or
sub-dictionaries following the same constraints."""
self._flushbits()
table_data = AMQPWriter()
for k, v in items(d):
table_data.write_shortstr(k)
table_data.write_item(v, k)
table_data = table_data.getvalue()
self.write_long(len(table_data))
self.out.write(table_data)
def write_item(self, v, k=None):
if isinstance(v, (string_t, bytes)):
if isinstance(v, string):
v = v.encode('utf-8')
self.write(b'S')
self.write_longstr(v)
elif isinstance(v, bool):
self.write(pack('>cB', b't', int(v)))
elif isinstance(v, float):
self.write(pack('>cd', b'd', v))
elif isinstance(v, int_types):
self.write(pack('>ci', b'I', v))
elif isinstance(v, Decimal):
self.write(b'D')
sign, digits, exponent = v.as_tuple()
v = 0
for d in digits:
v = (v * 10) + d
if sign:
v = -v
self.write_octet(-exponent)
self.write(pack('>i', v))
elif isinstance(v, datetime):
self.write(b'T')
self.write_timestamp(v)
## FIXME: timezone ?
elif isinstance(v, dict):
self.write(b'F')
self.write_table(v)
elif isinstance(v, (list, tuple)):
self.write(b'A')
self.write_array(v)
else:
err = (ILLEGAL_TABLE_TYPE_WITH_KEY.format(type(v), k, v) if k
else ILLEGAL_TABLE_TYPE.format(type(v), v))
raise FrameSyntaxError(err)
def write_array(self, a):
array_data = AMQPWriter()
for v in a:
array_data.write_item(v)
array_data = array_data.getvalue()
self.write_long(len(array_data))
self.out.write(array_data)
def write_timestamp(self, v):
"""Write out a Python datetime.datetime object as a 64-bit integer
representing seconds since the Unix epoch."""
self.out.write(pack('>q', long_t(mktime(v.timetuple()))))
class GenericContent(object):
"""Abstract base class for AMQP content.
Subclasses should override the PROPERTIES attribute.
"""
PROPERTIES = [('dummy', 'shortstr')]
def __init__(self, **props):
"""Save the properties appropriate to this AMQP content type
in a 'properties' dictionary."""
d = {}
for propname, _ in self.PROPERTIES:
if propname in props:
d[propname] = props[propname]
# FIXME: should we ignore unknown properties?
self.properties = d
def __eq__(self, other):
"""Check if this object has the same properties as another
content object."""
try:
return self.properties == other.properties
except AttributeError:
return NotImplemented
def __getattr__(self, name):
"""Look for additional properties in the 'properties'
dictionary, and if present - the 'delivery_info'
dictionary."""
if name == '__setstate__':
# Allows pickling/unpickling to work
raise AttributeError('__setstate__')
if name in self.properties:
return self.properties[name]
if 'delivery_info' in self.__dict__ \
and name in self.delivery_info:
return self.delivery_info[name]
raise AttributeError(name)
def _load_properties(self, raw_bytes):
"""Given the raw bytes containing the property-flags and property-list
from a content-frame-header, parse and insert into a dictionary
stored in this object as an attribute named 'properties'."""
r = AMQPReader(raw_bytes)
#
# Read 16-bit shorts until we get one with a low bit set to zero
#
flags = []
while 1:
flag_bits = r.read_short()
flags.append(flag_bits)
if flag_bits & 1 == 0:
break
shift = 0
d = {}
for key, proptype in self.PROPERTIES:
if shift == 0:
if not flags:
break
flag_bits, flags = flags[0], flags[1:]
shift = 15
if flag_bits & (1 << shift):
d[key] = getattr(r, 'read_' + proptype)()
shift -= 1
self.properties = d
def _serialize_properties(self):
"""serialize the 'properties' attribute (a dictionary) into
the raw bytes making up a set of property flags and a
property list, suitable for putting into a content frame header."""
shift = 15
flag_bits = 0
flags = []
raw_bytes = AMQPWriter()
for key, proptype in self.PROPERTIES:
val = self.properties.get(key, None)
if val is not None:
if shift == 0:
flags.append(flag_bits)
flag_bits = 0
shift = 15
flag_bits |= (1 << shift)
if proptype != 'bit':
getattr(raw_bytes, 'write_' + proptype)(val)
shift -= 1
flags.append(flag_bits)
result = AMQPWriter()
for flag_bits in flags:
result.write_short(flag_bits)
result.write(raw_bytes.getvalue())
return result.getvalue()
|