grpc/examples/python/interceptors/streaming/greeter_client.py

67 lines
2.3 KiB
Python

# Copyright 2023 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 Python implementation of the GRPC hellostreamingworld.MultiGreeter client."""
import logging
import grpc
import hellostreamingworld_pb2
import hellostreamingworld_pb2_grpc
def _wrap_response_iterator(interceptor_id, response_iterator):
for i, response in enumerate(response_iterator):
logging.info(f"{interceptor_id}: before response {i} returned")
yield response
logging.info(f"{interceptor_id}: after response {i} returned")
logging.info(f"{interceptor_id}: after RPC")
class UnaryStreamClientInterceptor(grpc.UnaryStreamClientInterceptor):
def __init__(self, interceptor_id):
self._interceptor_id = interceptor_id
def intercept_unary_stream(
self, continuation, client_call_details, request
):
logging.info(f"{self._interceptor_id}: before RPC")
response_iterator = continuation(client_call_details, request)
new_response_iterator = _wrap_response_iterator(
self._interceptor_id, response_iterator
)
return new_response_iterator
def run() -> None:
with grpc.insecure_channel(f"localhost:50051") as channel:
intercept_channel = grpc.intercept_channel(
channel,
UnaryStreamClientInterceptor("interceptor1"),
UnaryStreamClientInterceptor("interceptor2"),
UnaryStreamClientInterceptor("interceptor3"),
)
stub = hellostreamingworld_pb2_grpc.MultiGreeterStub(intercept_channel)
request = hellostreamingworld_pb2.HelloRequest(
name="Alice", num_greetings="2"
)
for response in stub.sayHello(request):
logging.info(response.message)
if __name__ == "__main__":
logging.basicConfig(level="INFO")
run()