client.py

from rpc_echo_python_client import Connection, HelloRequest


c = Connection("0.0.0.0:5000")
req = HelloRequest("Hello Request")
o = c.say_hello(req)

rpc_echo.proto

syntax = "proto3";

package rpc_echo;

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

// The request message containing the user's name.
message HelloRequest {
  bytes name = 1;
}

// The response message containing the greetings
message HelloReply {
  bytes message = 1;
}

server.py

from rpc_echo_python_server import MyGreeter, HelloRequest, HelloResponse


def say_hello(req: HelloRequest) -> HelloResponse:
  msg = req.message
  print(f"Got {msg}")
  return HelloResponse(f"Recieved {msg}!")


s = MyGreeter()
s.add_say_hello(say_hello)
s.run("0.0.0.0:5000")