1 # Copyright 2016 gRPC authors. 2 # 3 # Licensed under the Apache License, Version 2.0 (the "License"); 4 # you may not use this file except in compliance with the License. 5 # You may obtain a copy of the License at 6 # 7 # http://www.apache.org/licenses/LICENSE-2.0 8 # 9 # Unless required by applicable law or agreed to in writing, software 10 # distributed under the License is distributed on an "AS IS" BASIS, 11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 # See the License for the specific language governing permissions and 13 # limitations under the License. 14 15 import http2_base_server 16 import logging 17 import messages_pb2 18 19 # Set the number of padding bytes per data frame to be very large 20 # relative to the number of data bytes for each data frame sent. 21 _LARGE_PADDING_LENGTH = 255 22 _SMALL_READ_CHUNK_SIZE = 5 23 24 class TestDataFramePadding(object): 25 """ 26 In response to an incoming request, this test sends headers, followed by 27 data, followed by a reset stream frame. Client asserts that the RPC failed. 28 Client needs to deliver the complete message to the application layer. 29 """ 30 def __init__(self, use_padding=True): 31 self._base_server = http2_base_server.H2ProtocolBaseServer() 32 self._base_server._handlers['DataReceived'] = self.on_data_received 33 self._base_server._handlers['WindowUpdated'] = self.on_window_update 34 self._base_server._handlers['RequestReceived'] = self.on_request_received 35 36 # _total_updates maps stream ids to total flow control updates received 37 self._total_updates = {} 38 # zero window updates so far for connection window (stream id '0') 39 self._total_updates[0] = 0 40 self._read_chunk_size = _SMALL_READ_CHUNK_SIZE 41 42 if use_padding: 43 self._pad_length = _LARGE_PADDING_LENGTH 44 else: 45 self._pad_length = None 46 47 def get_base_server(self): 48 return self._base_server 49 50 def on_data_received(self, event): 51 logging.info('on data received. Stream id: %d. Data length: %d' % (event.stream_id, len(event.data))) 52 self._base_server.on_data_received_default(event) 53 if len(event.data) == 0: 54 return 55 sr = self._base_server.parse_received_data(event.stream_id) 56 stream_bytes = '' 57 # Check if full grpc msg has been read into the recv buffer yet 58 if sr: 59 response_data = self._base_server.default_response_data(sr.response_size) 60 logging.info('Stream id: %d. total resp size: %d' % (event.stream_id, len(response_data))) 61 # Begin sending the response. Add ``self._pad_length`` padding to each 62 # data frame and split the whole message into data frames each carrying 63 # only self._read_chunk_size of data. 64 # The purpose is to have the majority of the data frame response bytes 65 # be padding bytes, since ``self._pad_length`` >> ``self._read_chunk_size``. 66 self._base_server.setup_send(response_data , event.stream_id, pad_length=self._pad_length, read_chunk_size=self._read_chunk_size) 67 68 def on_request_received(self, event): 69 self._base_server.on_request_received_default(event) 70 logging.info('on request received. Stream id: %s.' % event.stream_id) 71 self._total_updates[event.stream_id] = 0 72 73 # Log debug info and try to resume sending on all currently active streams. 74 def on_window_update(self, event): 75 logging.info('on window update. Stream id: %s. Delta: %s' % (event.stream_id, event.delta)) 76 self._total_updates[event.stream_id] += event.delta 77 total = self._total_updates[event.stream_id] 78 logging.info('... - total updates for stream %d : %d' % (event.stream_id, total)) 79 self._base_server.on_window_update_default(event, pad_length=self._pad_length, read_chunk_size=self._read_chunk_size) 80
