49 lines
1.5 KiB
Python
49 lines
1.5 KiB
Python
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# -*- coding: utf-8 -*-
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"""
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hyper/common/decoder
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~~~~~~~~~~~~~~~~~~~~
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Contains hyper's code for handling compressed bodies.
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"""
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import zlib
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class DeflateDecoder(object):
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"""
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This is a decoding object that wraps ``zlib`` and is used for decoding
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deflated content.
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This rationale for the existence of this object is pretty unpleasant.
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The HTTP RFC specifies that 'deflate' is a valid content encoding. However,
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the spec _meant_ the zlib encoding form. Unfortunately, people who didn't
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read the RFC very carefully actually implemented a different form of
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'deflate'. Insanely, ``zlib`` handles them using two wbits values. This is
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such a mess it's hard to adequately articulate.
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This class was lovingly borrowed from the excellent urllib3 library under
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license: see NOTICES. If you ever see @shazow, you should probably buy him
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a drink or something.
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"""
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def __init__(self):
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self._first_try = True
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self._data = b''
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self._obj = zlib.decompressobj(zlib.MAX_WBITS)
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def __getattr__(self, name):
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return getattr(self._obj, name)
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def decompress(self, data):
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if not self._first_try:
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return self._obj.decompress(data)
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self._data += data
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try:
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return self._obj.decompress(data)
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except zlib.error:
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self._first_try = False
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self._obj = zlib.decompressobj(-zlib.MAX_WBITS)
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try:
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return self.decompress(self._data)
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finally:
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self._data = None
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