third_party/WebKit/LayoutTests/http/tests/websocket/permessage-deflate-manual_wsh.py

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  27 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28
  29
  30 import urlparse
  31 import zlib
  32 from mod_pywebsocket import common, util
  33 from mod_pywebsocket.extensions import PerMessageDeflateExtensionProcessor
  34 from mod_pywebsocket.extensions import ExtensionProcessorInterface
  35 from mod_pywebsocket.common import ExtensionParameter
  36
  37
  38 _GOODBYE_MESSAGE = u'Goodbye'
  39 _ENABLE_MESSAGE = u'EnableCompression'
  40 _DISABLE_MESSAGE = u'DisableCompression'
  41 _bfinal = False
  42 _client_max_window_bits = 15
  43
  44
  45 def _get_permessage_deflate_extension_processor(request):
  46     for extension_processor in request.ws_extension_processors:
  47         if isinstance(extension_processor,
  48                       PerMessageDeflateExtensionProcessor):
  49             return extension_processor
  50     return None
  51
  52
  53 def web_socket_do_extra_handshake(request):
  54     global _bfinal
  55     global _client_max_window_bits
  56     processor = _get_permessage_deflate_extension_processor(request)
  57     # Remove extension processors other than
  58     # PerMessageDeflateExtensionProcessor to avoid conflict.
  59     request.ws_extension_processors = [processor]
  60     if not processor:
  61         return
  62     r = request.ws_resource.split('?', 1)
  63     if len(r) == 1:
  64         return
  65     parameters = urlparse.parse_qs(r[1], keep_blank_values=True)
  66     if 'client_max_window_bits' in parameters:
  67         window_bits = int(parameters['client_max_window_bits'][0])
  68         processor.set_client_max_window_bits(window_bits)
  69         _client_max_window_bits = window_bits
  70     if 'client_no_context_takeover' in parameters:
  71         processor.set_client_no_context_takeover(True)
  72     if 'set_bfinal' in parameters:
  73         _bfinal = True
  74
  75
  76 def receive(request):
  77     stream = request.ws_stream
  78     possibly_compressed_body = b''
  79     compress = False
  80     while True:
  81         frame = stream._receive_frame_as_frame_object()
  82         if frame.opcode == common.OPCODE_CLOSE:
  83             message = stream._get_message_from_frame(frame)
  84             stream._process_close_message(message)
  85             return (False, None)
  86         compress = compress or frame.rsv1
  87         possibly_compressed_body += frame.payload
  88         if frame.fin:
  89             break
  90     if compress:
  91         return (compress, possibly_compressed_body + b'\x00\x00\xff\xff')
  92     else:
  93         return (compress, possibly_compressed_body)
  94
  95
  96 def web_socket_transfer_data(request):
  97     processor = _get_permessage_deflate_extension_processor(request)
  98     processor.set_bfinal(_bfinal)
  99     inflater = util._Inflater(_client_max_window_bits)
 100     while True:
 101         compress, possibly_compressed_body = receive(request)
 102         body = None
 103         if possibly_compressed_body is None:
 104             return
 105         if compress:
 106             inflater.append(possibly_compressed_body)
 107             body = inflater.decompress(-1)
 108         else:
 109             body = possibly_compressed_body
 110
 111         text = body.decode('utf-8')
 112         if processor:
 113             if text == _ENABLE_MESSAGE:
 114                 processor.enable_outgoing_compression()
 115             elif text == _DISABLE_MESSAGE:
 116                 processor.disable_outgoing_compression()
 117         request.ws_stream.send_message(text, binary=False)
 118         if text == _GOODBYE_MESSAGE:
 119             return
 120
 121
 122 # vi:sts=4 sw=4 et