| # Copyright 2019 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. |
| """The example of four ways of data transmission using gRPC in Python.""" |
| |
| from threading import Thread |
| from concurrent import futures |
| |
| import grpc |
| import demo_pb2_grpc |
| import demo_pb2 |
| |
| SERVER_ADDRESS = 'localhost:23333' |
| SERVER_ID = 1 |
| |
| |
| class DemoServer(demo_pb2_grpc.GRPCDemoServicer): |
| |
| # 一元模式(在一次调用中, 客户端只能向服务器传输一次请求数据, 服务器也只能返回一次响应) |
| # unary-unary(In a single call, the client can only send request once, and the server can |
| # only respond once.) |
| def SimpleMethod(self, request, context): |
| print("SimpleMethod called by client(%d) the message: %s" % |
| (request.client_id, request.request_data)) |
| response = demo_pb2.Response( |
| server_id=SERVER_ID, |
| response_data="Python server SimpleMethod Ok!!!!") |
| return response |
| |
| # 客户端流模式(在一次调用中, 客户端可以多次向服务器传输数据, 但是服务器只能返回一次响应) |
| # stream-unary (In a single call, the client can transfer data to the server several times, |
| # but the server can only return a response once.) |
| def ClientStreamingMethod(self, request_iterator, context): |
| print("ClientStreamingMethod called by client...") |
| for request in request_iterator: |
| print("recv from client(%d), message= %s" % |
| (request.client_id, request.request_data)) |
| response = demo_pb2.Response( |
| server_id=SERVER_ID, |
| response_data="Python server ClientStreamingMethod ok") |
| return response |
| |
| # 服务端流模式(在一次调用中, 客户端只能一次向服务器传输数据, 但是服务器可以多次返回响应) |
| # unary-stream (In a single call, the client can only transmit data to the server at one time, |
| # but the server can return the response many times.) |
| def ServerStreamingMethod(self, request, context): |
| print("ServerStreamingMethod called by client(%d), message= %s" % |
| (request.client_id, request.request_data)) |
| |
| # 创建一个生成器 |
| # create a generator |
| def response_messages(): |
| for i in range(5): |
| response = demo_pb2.Response( |
| server_id=SERVER_ID, |
| response_data=("send by Python server, message=%d" % i)) |
| yield response |
| |
| return response_messages() |
| |
| # 双向流模式 (在一次调用中, 客户端和服务器都可以向对方多次收发数据) |
| # stream-stream (In a single call, both client and server can send and receive data |
| # to each other multiple times.) |
| def BidirectionalStreamingMethod(self, request_iterator, context): |
| print("BidirectionalStreamingMethod called by client...") |
| |
| # 开启一个子线程去接收数据 |
| # Open a sub thread to receive data |
| def parse_request(): |
| for request in request_iterator: |
| print("recv from client(%d), message= %s" % |
| (request.client_id, request.request_data)) |
| |
| t = Thread(target=parse_request) |
| t.start() |
| |
| for i in range(5): |
| yield demo_pb2.Response( |
| server_id=SERVER_ID, |
| response_data=("send by Python server, message= %d" % i)) |
| |
| t.join() |
| |
| |
| def main(): |
| server = grpc.server(futures.ThreadPoolExecutor()) |
| |
| demo_pb2_grpc.add_GRPCDemoServicer_to_server(DemoServer(), server) |
| |
| server.add_insecure_port(SERVER_ADDRESS) |
| print("------------------start Python GRPC server") |
| server.start() |
| server.wait_for_termination() |
| |
| # If raise Error: |
| # AttributeError: '_Server' object has no attribute 'wait_for_termination' |
| # You can use the following code instead: |
| # import time |
| # while 1: |
| # time.sleep(10) |
| |
| |
| if __name__ == '__main__': |
| main() |