grpc：超時機制

工做中遇到一個問題，上游服務經過grpc調用下游服務，可是因爲下游服務負載過高致使上游服務的調用會隨機出現超時的狀況，可是有一點不太明確：超時以後，下游服務還會繼續進行計算麼？

因而本身寫了一個damon試了一下：

client：

 1 # Copyright 2015 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 """The Python implementation of the GRPC helloworld.Greeter client."""
15 
16 from __future__ import print_function
17 import logging
18 
19 import grpc
20 
21 import helloworld_pb2
22 import helloworld_pb2_grpc
23 
24 
25 def run():
26     # NOTE(gRPC Python Team): .close() is possible on a channel and should be
27     # used in circumstances in which the with statement does not fit the needs
28     # of the code.
29     with grpc.insecure_channel('localhost:50051') as channel:
30         stub = helloworld_pb2_grpc.GreeterStub(channel)
31         response = stub.SayHello(helloworld_pb2.HelloRequest(name='you'), timeout=30)
32     print("Greeter client received: " + response.message)
33 
34 
35 if __name__ == '__main__':
36     logging.basicConfig()
37     run()

View Code

server：

 1 # Copyright 2015 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 """The Python implementation of the GRPC helloworld.Greeter server."""
15 
16 from concurrent import futures
17 import time
18 import logging
19 
20 import grpc
21 
22 import helloworld_pb2
23 import helloworld_pb2_grpc
24 
25 _ONE_DAY_IN_SECONDS = 60 * 60 * 24
26 
27 
28 class Greeter(helloworld_pb2_grpc.GreeterServicer):
29 
30     def SayHello(self, request, context):
31     count = 0
32     while count < 10:
33         print('time:%s' % (time.time()))
34         time.sleep(5)
35         return helloworld_pb2.HelloReply(message='Hello, %s!' % request.name)
36 
37 
38 def serve():
39     server = grpc.server(futures.ThreadPoolExecutor(max_workers=10))
40     helloworld_pb2_grpc.add_GreeterServicer_to_server(Greeter(), server)
41     server.add_insecure_port('[::]:50051')
42     server.start()
43     try:
44         while True:
45             time.sleep(_ONE_DAY_IN_SECONDS)
46     except KeyboardInterrupt:
47         server.stop(0)
48 
49 
50 if __name__ == '__main__':
51     logging.basicConfig()
52     serve()

View Code

 這兩個例子就是在grpc官方提供的python例子上作了一下小的改動，獲得的結果是：當client超時報錯退出以後，server仍是會繼續進行計算，直到結束，那若是是這樣的話，超時的機制對於server來講是沒有做用的，即便client已經再也不等待這個結果了，可是server仍是會繼續計算，浪費server的資源。