Add python example - channel options

examples/python/helloworld/greeter_client_with_options.py

@@ -0,0 +1,50 @@
+# Copyright 2018 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 helloworld.Greeter client."""
+
+from __future__ import print_function
+
+import grpc
+
+import helloworld_pb2
+import helloworld_pb2_grpc
+
+
+def run():
+    # For more channel options, please see https://grpc.io/grpc/core/group__grpc__arg__keys.html
+    channel = grpc.insecure_channel(
+        target='localhost:50051',
+        options=[('grpc.lb_policy_name', 'pick_first'),
+                 ('grpc.enable_retries', 0),
+                 ('grpc.keepalive_timeout_ms', 10),
+                 ('grpc.max_receive_message_length', 12)])
+    stub = helloworld_pb2_grpc.GreeterStub(channel)
+
+    try:
+        # synchronous rpc call
+        stub.SayHello(helloworld_pb2.HelloRequest(name='you'))
+    except Exception as err:
+        print('Raised by max_receive_message_length option\n' + str(err))
+
+    try:
+        # asynchronous rpc call. timeout in second
+        future = stub.SayHello.future(helloworld_pb2.HelloRequest(name='me'), timeout=1)
+        response = future.result()
+        print("Greeter client received: " + response.message)
+    finally:
+        channel.close()
+
+
+if __name__ == '__main__':
+    run()