def _read_frame(self):
if self._frame_size == -1:
if self.length < SIZE_OF_FRAME_LENGTH_AND_FLAGS:
# we don't have even the frame length and flags ready
return False
self._read_frame_size_and_flags()
if self.length < self._frame_size:
return False
self._buf.seek(self._bytes_read)
size = self._frame_size
data = self._buf.read(size)
self._bytes_read += size
self._frame_size = -1
# No need to reset flags since it will be overwritten on the next read_frame_size_and_flags call
frame = Frame(data, self._frame_flags)
if not self._message:
self._message = InboundMessage(frame)
else:
self._message.add_frame(frame)
return True
class _Reader(object):
def __init__(self, builder):
self._buf = io.BytesIO()
self._builder = builder
self._bytes_read = 0
self._bytes_written = 0
self._frame_size = 0
self._frame_flags = 0
self._message = None
def read(self, data):
self._buf.seek(self._bytes_written)
self._buf.write(data)
self._bytes_written += len(data)
def process(self):
message = self._read_message()
while message:
self._builder.on_message(message)
message = self._read_message()
def _read_message(self):
while True:
if self._read_frame():
if self._message.end_frame.is_final_frame():
msg = self._message
self._reset()
return msg
else:
return None
def _read_frame(self):
n = self.length
if n < SIZE_OF_FRAME_LENGTH_AND_FLAGS:
# we don't have even the frame length and flags ready
return False
if self._frame_size == 0:
self._read_frame_size_and_flags()
if n < self._frame_size:
return False
self._buf.seek(self._bytes_read)
size = self._frame_size - SIZE_OF_FRAME_LENGTH_AND_FLAGS
data = self._buf.read(size)
self._bytes_read += size
self._frame_size = 0
# No need to reset flags since it will be overwritten on the next read_frame_size_and_flags call
frame = Frame(data, self._frame_flags)
if not self._message:
self._message = InboundMessage(frame)
else:
self._message.add_frame(frame)
return True
def _read_frame_size_and_flags(self):
self._buf.seek(self._bytes_read)
header_data = self._buf.read(SIZE_OF_FRAME_LENGTH_AND_FLAGS)
self._frame_size, self._frame_flags = _frame_header.unpack_from(
header_data, 0)
self._bytes_read += SIZE_OF_FRAME_LENGTH_AND_FLAGS
def _reset(self):
if self._bytes_written == self._bytes_read:
self._buf.seek(0)
self._buf.truncate()
self._bytes_written = 0
self._bytes_read = 0
self._message = None
@property
def length(self):
return self._bytes_written - self._bytes_read