1# Copyright 2019 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 example of four ways of data transmission using gRPC in Python.""" 15 16import time 17import grpc 18 19import demo_pb2_grpc 20import demo_pb2 21 22__all__ = [ 23 'simple_method', 'client_streaming_method', 'server_streaming_method', 24 'bidirectional_streaming_method' 25] 26 27SERVER_ADDRESS = "localhost:23333" 28CLIENT_ID = 1 29 30# 中文注释和英文翻译 31# Note that this example was contributed by an external user using Chinese comments. 32# In all cases, the Chinese comment text is translated to English just below it. 33 34 35# 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) 36# unary-unary(In a single call, the client can only send request once, and the server can 37# only respond once.) 38def simple_method(stub): 39 print("--------------Call SimpleMethod Begin--------------") 40 request = demo_pb2.Request(client_id=CLIENT_ID, 41 request_data="called by Python client") 42 response = stub.SimpleMethod(request) 43 print("resp from server(%d), the message=%s" % 44 (response.server_id, response.response_data)) 45 print("--------------Call SimpleMethod Over---------------") 46 47 48# 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） 49# stream-unary (In a single call, the client can transfer data to the server several times, 50# but the server can only return a response once.) 51def client_streaming_method(stub): 52 print("--------------Call ClientStreamingMethod Begin--------------") 53 54 # 创建一个生成器 55 # create a generator 56 def request_messages(): 57 for i in range(5): 58 request = demo_pb2.Request( 59 client_id=CLIENT_ID, 60 request_data=("called by Python client, message:%d" % i)) 61 yield request 62 63 response = stub.ClientStreamingMethod(request_messages()) 64 print("resp from server(%d), the message=%s" % 65 (response.server_id, response.response_data)) 66 print("--------------Call ClientStreamingMethod Over---------------") 67 68 69# 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） 70# unary-stream (In a single call, the client can only transmit data to the server at one time, 71# but the server can return the response many times.) 72def server_streaming_method(stub): 73 print("--------------Call ServerStreamingMethod Begin--------------") 74 request = demo_pb2.Request(client_id=CLIENT_ID, 75 request_data="called by Python client") 76 response_iterator = stub.ServerStreamingMethod(request) 77 for response in response_iterator: 78 print("recv from server(%d), message=%s" % 79 (response.server_id, response.response_data)) 80 81 print("--------------Call ServerStreamingMethod Over---------------") 82 83 84# 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) 85# stream-stream (In a single call, both client and server can send and receive data 86# to each other multiple times.) 87def bidirectional_streaming_method(stub): 88 print( 89 "--------------Call BidirectionalStreamingMethod Begin---------------") 90 91 # 创建一个生成器 92 # create a generator 93 def request_messages(): 94 for i in range(5): 95 request = demo_pb2.Request( 96 client_id=CLIENT_ID, 97 request_data=("called by Python client, message: %d" % i)) 98 yield request 99 time.sleep(1) 100 101 response_iterator = stub.BidirectionalStreamingMethod(request_messages()) 102 for response in response_iterator: 103 print("recv from server(%d), message=%s" % 104 (response.server_id, response.response_data)) 105 106 print("--------------Call BidirectionalStreamingMethod Over---------------") 107 108 109def main(): 110 with grpc.insecure_channel(SERVER_ADDRESS) as channel: 111 stub = demo_pb2_grpc.GRPCDemoStub(channel) 112 113 simple_method(stub) 114 115 client_streaming_method(stub) 116 117 server_streaming_method(stub) 118 119 bidirectional_streaming_method(stub) 120 121 122if __name__ == '__main__': 123 main() 124