def test_blocked_stream(self):
decoder = Decoder(0x100, 0x10)
stream_id = 0
# no streams unblocked
self.assertEqual(decoder.feed_encoder(b""), [])
# cannot resume non existent block
with self.assertRaises(ValueError):
decoder.resume_header(stream_id)
# the stream is blocked
with self.assertRaises(StreamBlocked):
decoder.feed_header(stream_id, binascii.unhexlify("0482d9101112"))
# the stream is still blocked
with self.assertRaises(StreamBlocked):
decoder.resume_header(stream_id)
# the stream becomes unblocked
self.assertEqual(
decoder.feed_encoder(
binascii.unhexlify(
"3fe10168f2b14939d69ce84f8d9635e9ef2a12bd454dc69a659f6cf2b14939d6"
"b505b161cc5a9385198fdad313c696dd6d5f4a082a65b6850400bea0837190dc"
"138a62d1bf")),
[stream_id],
)
# the header is resumed
control, headers = decoder.resume_header(stream_id)
self.assertEqual(control, b"\x80")
self.assertEqual(
headers,
[
(b":status", b"200"),
(b"x-echo-host", b"fb.mvfst.net:4433"),
(b"x-echo-user-agent", b"aioquic"),
(b"date", b"Sun, 21 Jul 2019 21:31:26 GMT"),
],
)
# free the decoder
del decoder
class H3Connection:
"""
A low-level HTTP/3 connection object.
:param quic: A :class:`~aioquic.connection.QuicConnection` instance.
"""
def __init__(self, quic: QuicConnection):
self._max_table_capacity = 0x100
self._blocked_streams = 0x10
self._is_client = quic.configuration.is_client
self._quic = quic
self._decoder = Decoder(self._max_table_capacity,
self._blocked_streams)
self._encoder = Encoder()
self._stream: Dict[int, H3Stream] = {}
self._local_control_stream_id: Optional[int] = None
self._local_decoder_stream_id: Optional[int] = None
self._local_encoder_stream_id: Optional[int] = None
self._peer_control_stream_id: Optional[int] = None
self._peer_decoder_stream_id: Optional[int] = None
self._peer_encoder_stream_id: Optional[int] = None
self._init_connection()
def handle_event(self, event: QuicEvent) -> List[HttpEvent]:
"""
Handle a QUIC event and return a list of HTTP events.
:param event: The QUIC event to handle.
"""
if isinstance(event, StreamDataReceived):
stream_id = event.stream_id
if stream_id not in self._stream:
self._stream[stream_id] = H3Stream()
if stream_id % 4 == 0:
return self._receive_stream_data_bidi(stream_id, event.data,
event.end_stream)
elif stream_is_unidirectional(stream_id):
return self._receive_stream_data_uni(stream_id, event.data)
return []
def send_data(self, stream_id: int, data: bytes, end_stream: bool) -> None:
"""
Send data on the given stream.
To retrieve datagram which need to be sent over the network call the QUIC
connection's :meth:`~aioquic.connection.QuicConnection.datagrams_to_send`
method.
:param stream_id: The stream ID on which to send the data.
:param data: The data to send.
:param end_stream: Whether to end the stream.
"""
self._quic.send_stream_data(stream_id,
encode_frame(FrameType.DATA, data),
end_stream)
def send_headers(self, stream_id: int, headers: Headers) -> None:
"""
Send headers on the given stream.
To retrieve datagram which need to be sent over the network call the QUIC
connection's :meth:`~aioquic.connection.QuicConnection.datagrams_to_send`
method.
:param stream_id: The stream ID on which to send the headers.
:param headers: The HTTP headers to send.
"""
encoder, header = self._encoder.encode(stream_id, 0, headers)
self._quic.send_stream_data(self._local_encoder_stream_id, encoder)
self._quic.send_stream_data(stream_id,
encode_frame(FrameType.HEADERS, header))
def _create_uni_stream(self, stream_type: int) -> int:
"""
Create an unidirectional stream of the given type.
"""
stream_id = self._quic.get_next_available_stream_id(
is_unidirectional=True)
self._quic.send_stream_data(stream_id, encode_uint_var(stream_type))
return stream_id
def _init_connection(self) -> None:
# send our settings
self._local_control_stream_id = self._create_uni_stream(
StreamType.CONTROL)
self._quic.send_stream_data(
self._local_control_stream_id,
encode_frame(
FrameType.SETTINGS,
encode_settings({
Setting.QPACK_MAX_TABLE_CAPACITY:
self._max_table_capacity,
Setting.QPACK_BLOCKED_STREAMS:
self._blocked_streams,
}),
),
)
# create encoder and decoder streams
self._local_encoder_stream_id = self._create_uni_stream(
StreamType.QPACK_ENCODER)
self._local_decoder_stream_id = self._create_uni_stream(
StreamType.QPACK_DECODER)
def _receive_stream_data_bidi(self, stream_id: int, data: bytes,
stream_ended: bool) -> List[HttpEvent]:
"""
Client-initiated bidirectional streams carry requests and responses.
"""
http_events: List[HttpEvent] = []
stream = self._stream[stream_id]
stream.buffer += data
if stream_ended:
stream.ended = True
if stream.blocked:
return http_events
# shortcut DATA frame bits
if (stream.frame_size is not None
and stream.frame_type == FrameType.DATA
and len(stream.buffer) < stream.frame_size):
http_events.append(
DataReceived(data=stream.buffer,
stream_id=stream_id,
stream_ended=False))
stream.frame_size -= len(stream.buffer)
stream.buffer = b""
return http_events
# some peers (e.g. f5) end the stream with no data
if stream_ended and not stream.buffer:
http_events.append(
DataReceived(data=b"", stream_id=stream_id, stream_ended=True))
return http_events
buf = Buffer(data=stream.buffer)
consumed = 0
while not buf.eof():
# fetch next frame header
if stream.frame_size is None:
try:
stream.frame_type = buf.pull_uint_var()
stream.frame_size = buf.pull_uint_var()
except BufferReadError:
break
consumed = buf.tell()
# check how much data is available
chunk_size = min(stream.frame_size, buf.capacity - consumed)
if (stream.frame_type == FrameType.HEADERS
and chunk_size < stream.frame_size):
break
# read available data
frame_data = buf.pull_bytes(chunk_size)
consumed = buf.tell()
# detect end of frame
stream.frame_size -= chunk_size
if not stream.frame_size:
stream.frame_size = None
if stream.frame_type == FrameType.DATA and (stream_ended
or frame_data):
http_events.append(
DataReceived(
data=frame_data,
stream_id=stream_id,
stream_ended=stream_ended and buf.eof(),
))
elif stream.frame_type == FrameType.HEADERS:
try:
decoder, headers = self._decoder.feed_header(
stream_id, frame_data)
except StreamBlocked:
stream.blocked = True
break
self._quic.send_stream_data(self._local_decoder_stream_id,
decoder)
cls = ResponseReceived if self._is_client else RequestReceived
http_events.append(
cls(
headers=headers,
stream_id=stream_id,
stream_ended=stream_ended and buf.eof(),
))
# remove processed data from buffer
stream.buffer = stream.buffer[consumed:]
return http_events
def _receive_stream_data_uni(self, stream_id: int,
data: bytes) -> List[HttpEvent]:
http_events: List[HttpEvent] = []
stream = self._stream[stream_id]
stream.buffer += data
buf = Buffer(data=stream.buffer)
consumed = 0
unblocked_streams: Set[int] = set()
while not buf.eof():
# fetch stream type for unidirectional streams
if stream.stream_type is None:
try:
stream.stream_type = buf.pull_uint_var()
except BufferReadError:
break
consumed = buf.tell()
if stream.stream_type == StreamType.CONTROL:
assert self._peer_control_stream_id is None
self._peer_control_stream_id = stream_id
elif stream.stream_type == StreamType.QPACK_DECODER:
assert self._peer_decoder_stream_id is None
self._peer_decoder_stream_id = stream_id
elif stream.stream_type == StreamType.QPACK_ENCODER:
assert self._peer_encoder_stream_id is None
self._peer_encoder_stream_id = stream_id
if stream_id == self._peer_control_stream_id:
# fetch next frame
try:
frame_type = buf.pull_uint_var()
frame_length = buf.pull_uint_var()
frame_data = buf.pull_bytes(frame_length)
except BufferReadError:
break
consumed = buf.tell()
# unidirectional control stream
if frame_type == FrameType.SETTINGS:
settings = parse_settings(frame_data)
encoder = self._encoder.apply_settings(
max_table_capacity=settings.get(
Setting.QPACK_MAX_TABLE_CAPACITY, 0),
blocked_streams=settings.get(
Setting.QPACK_BLOCKED_STREAMS, 0),
)
self._quic.send_stream_data(self._local_encoder_stream_id,
encoder)
else:
# fetch unframed data
data = buf.pull_bytes(buf.capacity - buf.tell())
consumed = buf.tell()
if stream_id == self._peer_decoder_stream_id:
self._encoder.feed_decoder(data)
elif stream_id == self._peer_encoder_stream_id:
unblocked_streams.update(self._decoder.feed_encoder(data))
# remove processed data from buffer
stream.buffer = stream.buffer[consumed:]
# process unblocked streams
for stream_id in unblocked_streams:
stream = self._stream[stream_id]
decoder, headers = self._decoder.resume_header(stream_id)
stream.blocked = False
cls = ResponseReceived if self._is_client else RequestReceived
http_events.append(
cls(
headers=headers,
stream_id=stream_id,
stream_ended=stream.ended and not stream.buffer,
))
http_events.extend(
self._receive_stream_data_bidi(stream_id, b"", stream.ended))
return http_events