xref: /aosp_15_r20/external/grpc-grpc/examples/python/lb_policies/greeter_client.py (revision cc02d7e222339f7a4f6ba5f422e6413f4bd931f2)
1# Copyright 2023 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
16import logging
17
18import grpc
19import helloworld_pb2
20import helloworld_pb2_grpc
21
22
23def run():
24    print("Will try to greet world ...")
25    options = (("grpc.lb_policy_name", "round_robin"),)
26    # Load balancing takes effect when the DNS server returns multiple IPs for the DNS hostname.
27    # Replace "localhost" with such hostname to see the round robin LB policy take effect.
28    with grpc.insecure_channel("localhost:50051", options=options) as channel:
29        stub = helloworld_pb2_grpc.GreeterStub(channel)
30        response = stub.SayHello(helloworld_pb2.HelloRequest(name="you"))
31    print("Greeter client received: " + response.message)
32
33
34if __name__ == "__main__":
35    logging.basicConfig()
36    run()
37