620 lines
27 KiB
Python
620 lines
27 KiB
Python
###############################################################################
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#
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# The MIT License (MIT)
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#
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# Copyright (c) Tavendo GmbH
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#
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# Permission is hereby granted, free of charge, to any person obtaining a copy
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# of this software and associated documentation files (the "Software"), to deal
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# in the Software without restriction, including without limitation the rights
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# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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# copies of the Software, and to permit persons to whom the Software is
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# furnished to do so, subject to the following conditions:
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#
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# The above copyright notice and this permission notice shall be included in
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# all copies or substantial portions of the Software.
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#
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# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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# THE SOFTWARE.
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#
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###############################################################################
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from __future__ import absolute_import
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import zlib
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from autobahn.websocket.compress_base import PerMessageCompressOffer, \
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PerMessageCompressOfferAccept, \
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PerMessageCompressResponse, \
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PerMessageCompressResponseAccept, \
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PerMessageCompress
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__all__ = (
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'PerMessageDeflateMixin',
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'PerMessageDeflateOffer',
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'PerMessageDeflateOfferAccept',
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'PerMessageDeflateResponse',
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'PerMessageDeflateResponseAccept',
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'PerMessageDeflate',
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)
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class PerMessageDeflateMixin:
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"""
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Mixin class for this extension.
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"""
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EXTENSION_NAME = "permessage-deflate"
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"""
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Name of this WebSocket extension.
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"""
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WINDOW_SIZE_PERMISSIBLE_VALUES = [8, 9, 10, 11, 12, 13, 14, 15]
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"""
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Permissible value for window size parameter.
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Higher values use more memory, but produce smaller output. The default is 15.
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"""
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MEM_LEVEL_PERMISSIBLE_VALUES = [1, 2, 3, 4, 5, 6, 7, 8, 9]
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"""
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Permissible value for memory level parameter.
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Higher values use more memory, but are faster and produce smaller output. The default is 8.
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"""
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class PerMessageDeflateOffer(PerMessageCompressOffer, PerMessageDeflateMixin):
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"""
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Set of extension parameters for `permessage-deflate` WebSocket extension
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offered by a client to a server.
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"""
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@classmethod
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def parse(cls, params):
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"""
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Parses a WebSocket extension offer for `permessage-deflate` provided by a client to a server.
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:param params: Output from :func:`autobahn.websocket.WebSocketProtocol._parseExtensionsHeader`.
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:type params: list
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:returns: object -- A new instance of :class:`autobahn.compress.PerMessageDeflateOffer`.
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"""
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# extension parameter defaults
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acceptMaxWindowBits = False
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acceptNoContextTakeover = True
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# acceptNoContextTakeover = False # FIXME: this may change in draft
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requestMaxWindowBits = 0
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requestNoContextTakeover = False
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# verify/parse client ("client-to-server direction") parameters of permessage-deflate offer
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for p in params:
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if len(params[p]) > 1:
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raise Exception("multiple occurrence of extension parameter '%s' for extension '%s'" % (p, cls.EXTENSION_NAME))
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val = params[p][0]
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if p == 'client_max_window_bits':
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##
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# see: https://tools.ietf.org/html/draft-ietf-hybi-permessage-compression-18
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# 8.1.2.2. client_max_window_bits
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# ".. This parameter has no value or a decimal integer value without
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# leading zeroes between 8 to 15 inclusive ..""
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# noinspection PySimplifyBooleanCheck
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if val is not True:
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try:
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val = int(val)
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except:
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raise Exception("illegal extension parameter value '%s' for parameter '%s' of extension '%s'" % (val, p, cls.EXTENSION_NAME))
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else:
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if val not in PerMessageDeflateMixin.WINDOW_SIZE_PERMISSIBLE_VALUES:
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raise Exception("illegal extension parameter value '%s' for parameter '%s' of extension '%s'" % (val, p, cls.EXTENSION_NAME))
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else:
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# FIXME (maybe): possibly forward/process the client hint!
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# acceptMaxWindowBits = val
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acceptMaxWindowBits = True
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else:
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acceptMaxWindowBits = True
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elif p == 'client_no_context_takeover':
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# noinspection PySimplifyBooleanCheck
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if val is not True:
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raise Exception("illegal extension parameter value '%s' for parameter '%s' of extension '%s'" % (val, p, cls.EXTENSION_NAME))
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else:
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acceptNoContextTakeover = True
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elif p == 'server_max_window_bits':
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try:
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val = int(val)
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except:
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raise Exception("illegal extension parameter value '%s' for parameter '%s' of extension '%s'" % (val, p, cls.EXTENSION_NAME))
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else:
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if val not in PerMessageDeflateMixin.WINDOW_SIZE_PERMISSIBLE_VALUES:
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raise Exception("illegal extension parameter value '%s' for parameter '%s' of extension '%s'" % (val, p, cls.EXTENSION_NAME))
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else:
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requestMaxWindowBits = val
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elif p == 'server_no_context_takeover':
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# noinspection PySimplifyBooleanCheck
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if val is not True:
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raise Exception("illegal extension parameter value '%s' for parameter '%s' of extension '%s'" % (val, p, cls.EXTENSION_NAME))
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else:
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requestNoContextTakeover = True
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else:
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raise Exception("illegal extension parameter '%s' for extension '%s'" % (p, cls.EXTENSION_NAME))
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offer = cls(acceptNoContextTakeover,
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acceptMaxWindowBits,
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requestNoContextTakeover,
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requestMaxWindowBits)
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return offer
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def __init__(self,
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acceptNoContextTakeover=True,
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acceptMaxWindowBits=True,
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requestNoContextTakeover=False,
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requestMaxWindowBits=0):
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"""
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Constructor.
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:param acceptNoContextTakeover: Iff true, client accepts "no context takeover" feature.
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:type acceptNoContextTakeover: bool
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:param acceptMaxWindowBits: Iff true, client accepts setting "max window size".
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:type acceptMaxWindowBits: bool
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:param requestNoContextTakeover: Iff true, client request "no context takeover" feature.
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:type requestNoContextTakeover: bool
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:param requestMaxWindowBits: Iff non-zero, client requests given "max window size" - must be 8-15.
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:type requestMaxWindowBits: int
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"""
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if type(acceptNoContextTakeover) != bool:
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raise Exception("invalid type %s for acceptNoContextTakeover" % type(acceptNoContextTakeover))
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self.acceptNoContextTakeover = acceptNoContextTakeover
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if type(acceptMaxWindowBits) != bool:
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raise Exception("invalid type %s for acceptMaxWindowBits" % type(acceptMaxWindowBits))
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self.acceptMaxWindowBits = acceptMaxWindowBits
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if type(requestNoContextTakeover) != bool:
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raise Exception("invalid type %s for requestNoContextTakeover" % type(requestNoContextTakeover))
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self.requestNoContextTakeover = requestNoContextTakeover
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if requestMaxWindowBits != 0 and requestMaxWindowBits not in self.WINDOW_SIZE_PERMISSIBLE_VALUES:
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raise Exception("invalid value %s for requestMaxWindowBits - permissible values %s" % (requestMaxWindowBits, self.WINDOW_SIZE_PERMISSIBLE_VALUES))
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self.requestMaxWindowBits = requestMaxWindowBits
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def getExtensionString(self):
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"""
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Returns the WebSocket extension configuration string as sent to the server.
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:returns: str -- PMCE configuration string.
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"""
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pmceString = self.EXTENSION_NAME
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if self.acceptNoContextTakeover:
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pmceString += "; client_no_context_takeover"
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if self.acceptMaxWindowBits:
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pmceString += "; client_max_window_bits"
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if self.requestNoContextTakeover:
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pmceString += "; server_no_context_takeover"
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if self.requestMaxWindowBits != 0:
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pmceString += "; server_max_window_bits=%d" % self.requestMaxWindowBits
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return pmceString
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def __json__(self):
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"""
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Returns a JSON serializable object representation.
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:returns: object -- JSON serializable representation.
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"""
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return {'extension': self.EXTENSION_NAME,
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'acceptNoContextTakeover': self.acceptNoContextTakeover,
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'acceptMaxWindowBits': self.acceptMaxWindowBits,
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'requestNoContextTakeover': self.requestNoContextTakeover,
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'requestMaxWindowBits': self.requestMaxWindowBits}
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def __repr__(self):
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"""
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Returns Python object representation that can be eval'ed to reconstruct the object.
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:returns: str -- Python string representation.
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"""
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return "PerMessageDeflateOffer(acceptNoContextTakeover = %s, acceptMaxWindowBits = %s, requestNoContextTakeover = %s, requestMaxWindowBits = %s)" % (self.acceptNoContextTakeover, self.acceptMaxWindowBits, self.requestNoContextTakeover, self.requestMaxWindowBits)
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class PerMessageDeflateOfferAccept(PerMessageCompressOfferAccept, PerMessageDeflateMixin):
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"""
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Set of parameters with which to accept an `permessage-deflate` offer
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from a client by a server.
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"""
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def __init__(self,
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offer,
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requestNoContextTakeover=False,
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requestMaxWindowBits=0,
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noContextTakeover=None,
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windowBits=None,
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memLevel=None):
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"""
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Constructor.
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:param offer: The offer being accepted.
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:type offer: Instance of :class:`autobahn.compress.PerMessageDeflateOffer`.
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:param requestNoContextTakeover: Iff true, server request "no context takeover" feature.
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:type requestNoContextTakeover: bool
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:param requestMaxCompressLevel: Iff non-zero, server requests given "maximum compression level" - must be 1-9.
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:type requestMaxCompressLevel: int
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:param noContextTakeover: Override server ("server-to-client direction") context takeover (this must be compatible with offer).
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:type noContextTakeover: bool
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:param windowBits: Override server ("server-to-client direction") window size (this must be compatible with offer).
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:type windowBits: int
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:param memLevel: Set server ("server-to-client direction") memory level.
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:type memLevel: int
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"""
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if not isinstance(offer, PerMessageDeflateOffer):
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raise Exception("invalid type %s for offer" % type(offer))
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self.offer = offer
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if type(requestNoContextTakeover) != bool:
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raise Exception("invalid type %s for requestNoContextTakeover" % type(requestNoContextTakeover))
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if requestNoContextTakeover and not offer.acceptNoContextTakeover:
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raise Exception("invalid value %s for requestNoContextTakeover - feature unsupported by client" % requestNoContextTakeover)
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self.requestNoContextTakeover = requestNoContextTakeover
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if requestMaxWindowBits != 0 and requestMaxWindowBits not in self.WINDOW_SIZE_PERMISSIBLE_VALUES:
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raise Exception("invalid value %s for requestMaxWindowBits - permissible values %s" % (requestMaxWindowBits, self.WINDOW_SIZE_PERMISSIBLE_VALUES))
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if requestMaxWindowBits != 0 and not offer.acceptMaxWindowBits:
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raise Exception("invalid value %s for requestMaxWindowBits - feature unsupported by client" % requestMaxWindowBits)
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self.requestMaxWindowBits = requestMaxWindowBits
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if noContextTakeover is not None:
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if type(noContextTakeover) != bool:
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raise Exception("invalid type %s for noContextTakeover" % type(noContextTakeover))
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if offer.requestNoContextTakeover and not noContextTakeover:
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raise Exception("invalid value %s for noContextTakeover - client requested feature" % noContextTakeover)
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self.noContextTakeover = noContextTakeover
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if windowBits is not None:
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if windowBits not in self.WINDOW_SIZE_PERMISSIBLE_VALUES:
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raise Exception("invalid value %s for windowBits - permissible values %s" % (windowBits, self.WINDOW_SIZE_PERMISSIBLE_VALUES))
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if offer.requestMaxWindowBits != 0 and windowBits > offer.requestMaxWindowBits:
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raise Exception("invalid value %s for windowBits - client requested lower maximum value" % windowBits)
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self.windowBits = windowBits
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if memLevel is not None:
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if memLevel not in self.MEM_LEVEL_PERMISSIBLE_VALUES:
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raise Exception("invalid value %s for memLevel - permissible values %s" % (memLevel, self.MEM_LEVEL_PERMISSIBLE_VALUES))
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self.memLevel = memLevel
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def getExtensionString(self):
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"""
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Returns the WebSocket extension configuration string as sent to the server.
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:returns: str -- PMCE configuration string.
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"""
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pmceString = self.EXTENSION_NAME
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if self.offer.requestNoContextTakeover:
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pmceString += "; server_no_context_takeover"
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if self.offer.requestMaxWindowBits != 0:
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pmceString += "; server_max_window_bits=%d" % self.offer.requestMaxWindowBits
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if self.requestNoContextTakeover:
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pmceString += "; client_no_context_takeover"
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if self.requestMaxWindowBits != 0:
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pmceString += "; client_max_window_bits=%d" % self.requestMaxWindowBits
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return pmceString
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def __json__(self):
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"""
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Returns a JSON serializable object representation.
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:returns: object -- JSON serializable representation.
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"""
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return {'extension': self.EXTENSION_NAME,
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'offer': self.offer.__json__(),
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'requestNoContextTakeover': self.requestNoContextTakeover,
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'requestMaxWindowBits': self.requestMaxWindowBits,
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'noContextTakeover': self.noContextTakeover,
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'windowBits': self.windowBits,
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'memLevel': self.memLevel}
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def __repr__(self):
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"""
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Returns Python object representation that can be eval'ed to reconstruct the object.
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:returns: str -- Python string representation.
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"""
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return "PerMessageDeflateOfferAccept(offer = %s, requestNoContextTakeover = %s, requestMaxWindowBits = %s, noContextTakeover = %s, windowBits = %s, memLevel = %s)" % (self.offer.__repr__(), self.requestNoContextTakeover, self.requestMaxWindowBits, self.noContextTakeover, self.windowBits, self.memLevel)
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class PerMessageDeflateResponse(PerMessageCompressResponse, PerMessageDeflateMixin):
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"""
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Set of parameters for `permessage-deflate` responded by server.
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"""
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@classmethod
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def parse(cls, params):
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"""
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Parses a WebSocket extension response for `permessage-deflate` provided by a server to a client.
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:param params: Output from :func:`autobahn.websocket.WebSocketProtocol._parseExtensionsHeader`.
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:type params: list
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:returns: object -- A new instance of :class:`autobahn.compress.PerMessageDeflateResponse`.
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"""
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client_max_window_bits = 0
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client_no_context_takeover = False
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server_max_window_bits = 0
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server_no_context_takeover = False
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for p in params:
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if len(params[p]) > 1:
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raise Exception("multiple occurrence of extension parameter '%s' for extension '%s'" % (p, cls.EXTENSION_NAME))
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val = params[p][0]
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if p == 'client_max_window_bits':
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try:
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val = int(val)
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except:
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raise Exception("illegal extension parameter value '%s' for parameter '%s' of extension '%s'" % (val, p, cls.EXTENSION_NAME))
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else:
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if val not in PerMessageDeflateMixin.WINDOW_SIZE_PERMISSIBLE_VALUES:
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raise Exception("illegal extension parameter value '%s' for parameter '%s' of extension '%s'" % (val, p, cls.EXTENSION_NAME))
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else:
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client_max_window_bits = val
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elif p == 'client_no_context_takeover':
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# noinspection PySimplifyBooleanCheck
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if val is not True:
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raise Exception("illegal extension parameter value '%s' for parameter '%s' of extension '%s'" % (val, p, cls.EXTENSION_NAME))
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else:
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client_no_context_takeover = True
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elif p == 'server_max_window_bits':
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try:
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val = int(val)
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except:
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raise Exception("illegal extension parameter value '%s' for parameter '%s' of extension '%s'" % (val, p, cls.EXTENSION_NAME))
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else:
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if val not in PerMessageDeflateMixin.WINDOW_SIZE_PERMISSIBLE_VALUES:
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raise Exception("illegal extension parameter value '%s' for parameter '%s' of extension '%s'" % (val, p, cls.EXTENSION_NAME))
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else:
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server_max_window_bits = val
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elif p == 'server_no_context_takeover':
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# noinspection PySimplifyBooleanCheck
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if val is not True:
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raise Exception("illegal extension parameter value '%s' for parameter '%s' of extension '%s'" % (val, p, cls.EXTENSION_NAME))
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else:
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server_no_context_takeover = True
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else:
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raise Exception("illegal extension parameter '%s' for extension '%s'" % (p, cls.EXTENSION_NAME))
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response = cls(client_max_window_bits,
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client_no_context_takeover,
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server_max_window_bits,
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server_no_context_takeover)
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return response
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def __init__(self,
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client_max_window_bits,
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client_no_context_takeover,
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server_max_window_bits,
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server_no_context_takeover):
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self.client_max_window_bits = client_max_window_bits
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self.client_no_context_takeover = client_no_context_takeover
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self.server_max_window_bits = server_max_window_bits
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self.server_no_context_takeover = server_no_context_takeover
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def __json__(self):
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"""
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Returns a JSON serializable object representation.
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:returns: object -- JSON serializable representation.
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"""
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return {'extension': self.EXTENSION_NAME,
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'client_max_window_bits': self.client_max_window_bits,
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'client_no_context_takeover': self.client_no_context_takeover,
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'server_max_window_bits': self.server_max_window_bits,
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'server_no_context_takeover': self.server_no_context_takeover}
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def __repr__(self):
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"""
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Returns Python object representation that can be eval'ed to reconstruct the object.
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:returns: str -- Python string representation.
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"""
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return "PerMessageDeflateResponse(client_max_window_bits = %s, client_no_context_takeover = %s, server_max_window_bits = %s, server_no_context_takeover = %s)" % (self.client_max_window_bits, self.client_no_context_takeover, self.server_max_window_bits, self.server_no_context_takeover)
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class PerMessageDeflateResponseAccept(PerMessageCompressResponseAccept, PerMessageDeflateMixin):
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"""
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Set of parameters with which to accept an `permessage-deflate` response
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from a server by a client.
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"""
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def __init__(self,
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response,
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noContextTakeover=None,
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windowBits=None,
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memLevel=None):
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"""
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Constructor.
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:param response: The response being accepted.
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:type response: Instance of :class:`autobahn.compress.PerMessageDeflateResponse`.
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:param noContextTakeover: Override client ("client-to-server direction") context takeover (this must be compatible with response).
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:type noContextTakeover: bool
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:param windowBits: Override client ("client-to-server direction") window size (this must be compatible with response).
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:type windowBits: int
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:param memLevel: Set client ("client-to-server direction") memory level.
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:type memLevel: int
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"""
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if not isinstance(response, PerMessageDeflateResponse):
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raise Exception("invalid type %s for response" % type(response))
|
|
|
|
self.response = response
|
|
|
|
if noContextTakeover is not None:
|
|
if type(noContextTakeover) != bool:
|
|
raise Exception("invalid type %s for noContextTakeover" % type(noContextTakeover))
|
|
|
|
if response.client_no_context_takeover and not noContextTakeover:
|
|
raise Exception("invalid value %s for noContextTakeover - server requested feature" % noContextTakeover)
|
|
|
|
self.noContextTakeover = noContextTakeover
|
|
|
|
if windowBits is not None:
|
|
if windowBits not in self.WINDOW_SIZE_PERMISSIBLE_VALUES:
|
|
raise Exception("invalid value %s for windowBits - permissible values %s" % (windowBits, self.WINDOW_SIZE_PERMISSIBLE_VALUES))
|
|
|
|
if response.client_max_window_bits != 0 and windowBits > response.client_max_window_bits:
|
|
raise Exception("invalid value %s for windowBits - server requested lower maximum value" % windowBits)
|
|
|
|
self.windowBits = windowBits
|
|
|
|
if memLevel is not None:
|
|
if memLevel not in self.MEM_LEVEL_PERMISSIBLE_VALUES:
|
|
raise Exception("invalid value %s for memLevel - permissible values %s" % (memLevel, self.MEM_LEVEL_PERMISSIBLE_VALUES))
|
|
|
|
self.memLevel = memLevel
|
|
|
|
def __json__(self):
|
|
"""
|
|
Returns a JSON serializable object representation.
|
|
|
|
:returns: object -- JSON serializable representation.
|
|
"""
|
|
return {'extension': self.EXTENSION_NAME,
|
|
'response': self.response.__json__(),
|
|
'noContextTakeover': self.noContextTakeover,
|
|
'windowBits': self.windowBits,
|
|
'memLevel': self.memLevel}
|
|
|
|
def __repr__(self):
|
|
"""
|
|
Returns Python object representation that can be eval'ed to reconstruct the object.
|
|
|
|
:returns: str -- Python string representation.
|
|
"""
|
|
return "PerMessageDeflateResponseAccept(response = %s, noContextTakeover = %s, windowBits = %s, memLevel = %s)" % (self.response.__repr__(), self.noContextTakeover, self.windowBits, self.memLevel)
|
|
|
|
|
|
# noinspection PyArgumentList
|
|
class PerMessageDeflate(PerMessageCompress, PerMessageDeflateMixin):
|
|
"""
|
|
`permessage-deflate` WebSocket extension processor.
|
|
"""
|
|
DEFAULT_WINDOW_BITS = zlib.MAX_WBITS
|
|
DEFAULT_MEM_LEVEL = 8
|
|
|
|
@classmethod
|
|
def createFromResponseAccept(cls, isServer, accept):
|
|
# accept: instance of PerMessageDeflateResponseAccept
|
|
pmce = cls(isServer,
|
|
accept.response.server_no_context_takeover,
|
|
accept.noContextTakeover if accept.noContextTakeover is not None else accept.response.client_no_context_takeover,
|
|
accept.response.server_max_window_bits,
|
|
accept.windowBits if accept.windowBits is not None else accept.response.client_max_window_bits,
|
|
accept.memLevel)
|
|
return pmce
|
|
|
|
@classmethod
|
|
def createFromOfferAccept(cls, isServer, accept):
|
|
# accept: instance of PerMessageDeflateOfferAccept
|
|
pmce = cls(isServer,
|
|
accept.noContextTakeover if accept.noContextTakeover is not None else accept.offer.requestNoContextTakeover,
|
|
accept.requestNoContextTakeover,
|
|
accept.windowBits if accept.windowBits is not None else accept.offer.requestMaxWindowBits,
|
|
accept.requestMaxWindowBits,
|
|
accept.memLevel)
|
|
return pmce
|
|
|
|
def __init__(self,
|
|
isServer,
|
|
server_no_context_takeover,
|
|
client_no_context_takeover,
|
|
server_max_window_bits,
|
|
client_max_window_bits,
|
|
mem_level):
|
|
self._isServer = isServer
|
|
|
|
self.server_no_context_takeover = server_no_context_takeover
|
|
self.client_no_context_takeover = client_no_context_takeover
|
|
|
|
self.server_max_window_bits = server_max_window_bits if server_max_window_bits != 0 else self.DEFAULT_WINDOW_BITS
|
|
self.client_max_window_bits = client_max_window_bits if client_max_window_bits != 0 else self.DEFAULT_WINDOW_BITS
|
|
|
|
self.mem_level = mem_level if mem_level else self.DEFAULT_MEM_LEVEL
|
|
|
|
self._compressor = None
|
|
self._decompressor = None
|
|
|
|
def __json__(self):
|
|
return {'extension': self.EXTENSION_NAME,
|
|
'isServer': self._isServer,
|
|
'server_no_context_takeover': self.server_no_context_takeover,
|
|
'client_no_context_takeover': self.client_no_context_takeover,
|
|
'server_max_window_bits': self.server_max_window_bits,
|
|
'client_max_window_bits': self.client_max_window_bits,
|
|
'mem_level': self.mem_level}
|
|
|
|
def __repr__(self):
|
|
return "PerMessageDeflate(isServer = %s, server_no_context_takeover = %s, client_no_context_takeover = %s, server_max_window_bits = %s, client_max_window_bits = %s, mem_level = %s)" % (self._isServer, self.server_no_context_takeover, self.client_no_context_takeover, self.server_max_window_bits, self.client_max_window_bits, self.mem_level)
|
|
|
|
def startCompressMessage(self):
|
|
# compressobj([level[, method[, wbits[, memlevel[, strategy]]]]])
|
|
# http://bugs.python.org/issue19278
|
|
# http://hg.python.org/cpython/rev/c54c8e71b79a
|
|
if self._isServer:
|
|
if self._compressor is None or self.server_no_context_takeover:
|
|
self._compressor = zlib.compressobj(zlib.Z_DEFAULT_COMPRESSION, zlib.DEFLATED, -self.server_max_window_bits, self.mem_level)
|
|
else:
|
|
if self._compressor is None or self.client_no_context_takeover:
|
|
self._compressor = zlib.compressobj(zlib.Z_DEFAULT_COMPRESSION, zlib.DEFLATED, -self.client_max_window_bits, self.mem_level)
|
|
|
|
def compressMessageData(self, data):
|
|
return self._compressor.compress(data)
|
|
|
|
def endCompressMessage(self):
|
|
data = self._compressor.flush(zlib.Z_SYNC_FLUSH)
|
|
return data[:-4]
|
|
|
|
def startDecompressMessage(self):
|
|
if self._isServer:
|
|
if self._decompressor is None or self.client_no_context_takeover:
|
|
self._decompressor = zlib.decompressobj(-self.client_max_window_bits)
|
|
else:
|
|
if self._decompressor is None or self.server_no_context_takeover:
|
|
self._decompressor = zlib.decompressobj(-self.server_max_window_bits)
|
|
|
|
def decompressMessageData(self, data):
|
|
return self._decompressor.decompress(data)
|
|
|
|
def endDecompressMessage(self):
|
|
# Eat stripped LEN and NLEN field of a non-compressed block added
|
|
# for Z_SYNC_FLUSH.
|
|
self._decompressor.decompress(b'\x00\x00\xff\xff')
|