基于前两篇，本篇介绍下如果用Java和Python通过gRPC互相调用

安装依赖

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pip install grpcio
pip install grpcbuf
pip install grpcio-tools

准备.proto文件

注意，该文件需要与Java项目中的.proto保持一致

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syntax = "proto3";
package example;

// The greeting service definition.
service Greeter {
  // Sends a greeting
  rpc SayHello (HelloRequest) returns (HelloReply) {}
}

// The request message containing the user's name.
message HelloRequest {
  string name = 1;
}
// The response message containing the greetings
message HelloReply {
  string message = 1;
}

生成Python代码

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python -m grpc_tools.protoc -I . --python_out=. --grpc_python_out=. example/helloworld.proto

编写Python Client

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#! /usr/bin/env python
# -*- coding: utf-8 -*-
# from __future__ import print_function
import grpc
from example import helloworld_pb2, helloworld_pb2_grpc


def run():
    # NOTE(gRPC Python Team): .close() is possible on a channel and should be
    # used in circumstances in which the with statement does not fit the needs
    # of the code.
    with grpc.insecure_channel('10.10.10.10:50051') as channel:
        stub = helloworld_pb2_grpc.GreeterStub(channel)
        response = stub.SayHello(helloworld_pb2.HelloRequest(name='you'))
    print("Greeter client received: " + response.message)


if __name__ == '__main__':
    run()

grpc.insecure_channel(‘localhost:50051’) 有可能会提示failed to connect to all addresses错误，我将其修改为网卡绑定的局域网地址便可成功访问Java服务。

编写Python Server

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#! /usr/bin/env python
# -*- coding: utf-8 -*-

import time
import sys
import grpc
from concurrent import futures

from example import helloworld_pb2, helloworld_pb2_grpc
from example import helloworld_pb2 as helloworld__pb2
_ONE_DAY_IN_SECONDS = 60 * 60 * 24


class Greeter(helloworld_pb2_grpc.GreeterServicer):

    def SayHello(self, request, context):
        return helloworld_pb2.HelloReply(message='Hello, %s!' % request.name)


def serve():
    server = grpc.server(futures.ThreadPoolExecutor(max_workers=10))
    helloworld_pb2_grpc.add_GreeterServicer_to_server(Greeter(), server)
    server.add_insecure_port('[::]:50051')
    server.start()
    try:
        while True:
            time.sleep(_ONE_DAY_IN_SECONDS)
    except KeyboardInterrupt:
        server.stop(0)


if __name__ == '__main__':

    serve()

这样，就可以实现Python Client 调用 Java gRPC server , Java Client 调用 Python gRPC server。

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/home/charles/miniconda3/bin/conda run -n py_grpc --no-capture-output python /mnt/d/PycharmProjects/pygrpc/client/greeter_client.py 
Greeter client received: Hello you