| # Copyright 2016 gRPC authors. |
| # |
| # Licensed under the Apache License, Version 2.0 (the "License"); |
| # you may not use this file except in compliance with the License. |
| # You may obtain a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, software |
| # distributed under the License is distributed on an "AS IS" BASIS, |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| # See the License for the specific language governing permissions and |
| # limitations under the License. |
| |
| import logging |
| import struct |
| |
| import h2 |
| import h2.connection |
| import messages_pb2 |
| import twisted |
| import twisted.internet |
| import twisted.internet.protocol |
| |
| _READ_CHUNK_SIZE = 16384 |
| _GRPC_HEADER_SIZE = 5 |
| _MIN_SETTINGS_MAX_FRAME_SIZE = 16384 |
| |
| |
| class H2ProtocolBaseServer(twisted.internet.protocol.Protocol): |
| def __init__(self): |
| self._conn = h2.connection.H2Connection(client_side=False) |
| self._recv_buffer = {} |
| self._handlers = {} |
| self._handlers["ConnectionMade"] = self.on_connection_made_default |
| self._handlers["DataReceived"] = self.on_data_received_default |
| self._handlers["WindowUpdated"] = self.on_window_update_default |
| self._handlers["RequestReceived"] = self.on_request_received_default |
| self._handlers["SendDone"] = self.on_send_done_default |
| self._handlers["ConnectionLost"] = self.on_connection_lost |
| self._handlers["PingAcknowledged"] = self.on_ping_acknowledged_default |
| self._stream_status = {} |
| self._send_remaining = {} |
| self._outstanding_pings = 0 |
| |
| def set_handlers(self, handlers): |
| self._handlers = handlers |
| |
| def connectionMade(self): |
| self._handlers["ConnectionMade"]() |
| |
| def connectionLost(self, reason): |
| self._handlers["ConnectionLost"](reason) |
| |
| def on_connection_made_default(self): |
| logging.info("Connection Made") |
| self._conn.initiate_connection() |
| self.transport.setTcpNoDelay(True) |
| self.transport.write(self._conn.data_to_send()) |
| |
| def on_connection_lost(self, reason): |
| logging.info("Disconnected %s" % reason) |
| |
| def dataReceived(self, data): |
| try: |
| events = self._conn.receive_data(data) |
| except h2.exceptions.ProtocolError: |
| # this try/except block catches exceptions due to race between sending |
| # GOAWAY and processing a response in flight. |
| return |
| if self._conn.data_to_send: |
| self.transport.write(self._conn.data_to_send()) |
| for event in events: |
| if isinstance( |
| event, h2.events.RequestReceived |
| ) and self._handlers.has_key("RequestReceived"): |
| logging.info( |
| "RequestReceived Event for stream: %d" % event.stream_id |
| ) |
| self._handlers["RequestReceived"](event) |
| elif isinstance( |
| event, h2.events.DataReceived |
| ) and self._handlers.has_key("DataReceived"): |
| logging.info( |
| "DataReceived Event for stream: %d" % event.stream_id |
| ) |
| self._handlers["DataReceived"](event) |
| elif isinstance( |
| event, h2.events.WindowUpdated |
| ) and self._handlers.has_key("WindowUpdated"): |
| logging.info( |
| "WindowUpdated Event for stream: %d" % event.stream_id |
| ) |
| self._handlers["WindowUpdated"](event) |
| elif isinstance( |
| event, h2.events.PingAcknowledged |
| ) and self._handlers.has_key("PingAcknowledged"): |
| logging.info("PingAcknowledged Event") |
| self._handlers["PingAcknowledged"](event) |
| self.transport.write(self._conn.data_to_send()) |
| |
| def on_ping_acknowledged_default(self, event): |
| logging.info("ping acknowledged") |
| self._outstanding_pings -= 1 |
| |
| def on_data_received_default(self, event): |
| self._conn.acknowledge_received_data(len(event.data), event.stream_id) |
| self._recv_buffer[event.stream_id] += event.data |
| |
| def on_request_received_default(self, event): |
| self._recv_buffer[event.stream_id] = "" |
| self._stream_id = event.stream_id |
| self._stream_status[event.stream_id] = True |
| self._conn.send_headers( |
| stream_id=event.stream_id, |
| headers=[ |
| (":status", "200"), |
| ("content-type", "application/grpc"), |
| ("grpc-encoding", "identity"), |
| ("grpc-accept-encoding", "identity,deflate,gzip"), |
| ], |
| ) |
| self.transport.write(self._conn.data_to_send()) |
| |
| def on_window_update_default( |
| self, _, pad_length=None, read_chunk_size=_READ_CHUNK_SIZE |
| ): |
| # try to resume sending on all active streams (update might be for connection) |
| for stream_id in self._send_remaining: |
| self.default_send( |
| stream_id, |
| pad_length=pad_length, |
| read_chunk_size=read_chunk_size, |
| ) |
| |
| def send_reset_stream(self): |
| self._conn.reset_stream(self._stream_id) |
| self.transport.write(self._conn.data_to_send()) |
| |
| def setup_send( |
| self, |
| data_to_send, |
| stream_id, |
| pad_length=None, |
| read_chunk_size=_READ_CHUNK_SIZE, |
| ): |
| logging.info("Setting up data to send for stream_id: %d" % stream_id) |
| self._send_remaining[stream_id] = len(data_to_send) |
| self._send_offset = 0 |
| self._data_to_send = data_to_send |
| self.default_send( |
| stream_id, pad_length=pad_length, read_chunk_size=read_chunk_size |
| ) |
| |
| def default_send( |
| self, stream_id, pad_length=None, read_chunk_size=_READ_CHUNK_SIZE |
| ): |
| if not self._send_remaining.has_key(stream_id): |
| # not setup to send data yet |
| return |
| |
| while self._send_remaining[stream_id] > 0: |
| lfcw = self._conn.local_flow_control_window(stream_id) |
| padding_bytes = pad_length + 1 if pad_length is not None else 0 |
| if lfcw - padding_bytes <= 0: |
| logging.info( |
| "Stream %d. lfcw: %d. padding bytes: %d. not enough" |
| " quota yet" % (stream_id, lfcw, padding_bytes) |
| ) |
| break |
| chunk_size = min(lfcw - padding_bytes, read_chunk_size) |
| bytes_to_send = min(chunk_size, self._send_remaining[stream_id]) |
| logging.info( |
| "flow_control_window = %d. sending [%d:%d] stream_id %d." |
| " includes %d total padding bytes" |
| % ( |
| lfcw, |
| self._send_offset, |
| self._send_offset + bytes_to_send + padding_bytes, |
| stream_id, |
| padding_bytes, |
| ) |
| ) |
| # The receiver might allow sending frames larger than the http2 minimum |
| # max frame size (16384), but this test should never send more than 16384 |
| # for simplicity (which is always legal). |
| if bytes_to_send + padding_bytes > _MIN_SETTINGS_MAX_FRAME_SIZE: |
| raise ValueError( |
| "overload: sending %d" % (bytes_to_send + padding_bytes) |
| ) |
| data = self._data_to_send[ |
| self._send_offset : self._send_offset + bytes_to_send |
| ] |
| try: |
| self._conn.send_data( |
| stream_id, data, end_stream=False, pad_length=pad_length |
| ) |
| except h2.exceptions.ProtocolError: |
| logging.info("Stream %d is closed" % stream_id) |
| break |
| self._send_remaining[stream_id] -= bytes_to_send |
| self._send_offset += bytes_to_send |
| if self._send_remaining[stream_id] == 0: |
| self._handlers["SendDone"](stream_id) |
| |
| def default_ping(self): |
| logging.info("sending ping") |
| self._outstanding_pings += 1 |
| self._conn.ping(b"\x00" * 8) |
| self.transport.write(self._conn.data_to_send()) |
| |
| def on_send_done_default(self, stream_id): |
| if self._stream_status[stream_id]: |
| self._stream_status[stream_id] = False |
| self.default_send_trailer(stream_id) |
| else: |
| logging.error("Stream %d is already closed" % stream_id) |
| |
| def default_send_trailer(self, stream_id): |
| logging.info("Sending trailer for stream id %d" % stream_id) |
| self._conn.send_headers( |
| stream_id, headers=[("grpc-status", "0")], end_stream=True |
| ) |
| self.transport.write(self._conn.data_to_send()) |
| |
| @staticmethod |
| def default_response_data(response_size): |
| sresp = messages_pb2.SimpleResponse() |
| sresp.payload.body = b"\x00" * response_size |
| serialized_resp_proto = sresp.SerializeToString() |
| response_data = ( |
| b"\x00" |
| + struct.pack("i", len(serialized_resp_proto))[::-1] |
| + serialized_resp_proto |
| ) |
| return response_data |
| |
| def parse_received_data(self, stream_id): |
| """returns a grpc framed string of bytes containing response proto of the size |
| asked in request""" |
| recv_buffer = self._recv_buffer[stream_id] |
| grpc_msg_size = struct.unpack("i", recv_buffer[1:5][::-1])[0] |
| if len(recv_buffer) != _GRPC_HEADER_SIZE + grpc_msg_size: |
| return None |
| req_proto_str = recv_buffer[5 : 5 + grpc_msg_size] |
| sr = messages_pb2.SimpleRequest() |
| sr.ParseFromString(req_proto_str) |
| logging.info("Parsed simple request for stream %d" % stream_id) |
| return sr |
