Add a hello world example for grpc integration (#99)

Author: liyanhui1228

examples/trace/grpc/hello_world.proto

@@ -0,0 +1,31 @@
+// Copyright 2017, OpenCensus 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.
+
+syntax = "proto3";
+
+// The hello world service definition.
+service HelloWorld {
+  // Say hello to the request sender (unary-unary)
+  rpc SayHello (HelloRequest) returns (HelloReply) {}
+}
+
+// The request message containing the sender's name.
+message HelloRequest {
+  string name = 1;
+}
+
+// The response message containing the greetings
+message HelloReply {
+  string message = 1;
+}

examples/trace/grpc/hello_world_client.py

@@ -0,0 +1,43 @@
+# Copyright 2017, OpenCensus 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.
+
+from __future__ import print_function
+
+import grpc
+
+import hello_world_pb2
+import hello_world_pb2_grpc
+
+from opencensus.trace.tracer import Tracer
+from opencensus.trace.exporters import stackdriver_exporter
+from opencensus.trace.ext.grpc import client_interceptor
+
+HOST_PORT = 'localhost:50051'
+
+
+def main():
+    exporter = stackdriver_exporter.StackdriverExporter()
+    tracer = Tracer(exporter=exporter)
+    tracer_interceptor = client_interceptor.OpenCensusClientInterceptor(
+        tracer,
+        host_port=HOST_PORT)
+    channel = grpc.insecure_channel(HOST_PORT)
+    channel = grpc.intercept_channel(channel, tracer_interceptor)
+    stub = hello_world_pb2_grpc.HelloWorldStub(channel)
+    response = stub.SayHello(hello_world_pb2.HelloRequest(name='you'))
+    print("Message received: " + response.message)
+
+
+if __name__ == '__main__':
+    main()

examples/trace/grpc/hello_world_pb2.py

@@ -0,0 +1,46 @@
+# Generated by the gRPC Python protocol compiler plugin. DO NOT EDIT!
+import grpc
+
+import hello_world_pb2 as hello__world__pb2
+
+
+class HelloWorldStub(object):
+  """The hello world service definition.
+  """
+
+  def __init__(self, channel):
+    """Constructor.
+
+    Args:
+      channel: A grpc.Channel.
+    """
+    self.SayHello = channel.unary_unary(
+        '/HelloWorld/SayHello',
+        request_serializer=hello__world__pb2.HelloRequest.SerializeToString,
+        response_deserializer=hello__world__pb2.HelloReply.FromString,
+        )
+
+
+class HelloWorldServicer(object):
+  """The hello world service definition.
+  """
+
+  def SayHello(self, request, context):
+    """Say hello to the request sender (unary-unary)
+    """
+    context.set_code(grpc.StatusCode.UNIMPLEMENTED)
+    context.set_details('Method not implemented!')
+    raise NotImplementedError('Method not implemented!')
+
+
+def add_HelloWorldServicer_to_server(servicer, server):
+  rpc_method_handlers = {
+      'SayHello': grpc.unary_unary_rpc_method_handler(
+          servicer.SayHello,
+          request_deserializer=hello__world__pb2.HelloRequest.FromString,
+          response_serializer=hello__world__pb2.HelloReply.SerializeToString,
+      ),
+  }
+  generic_handler = grpc.method_handlers_generic_handler(
+      'HelloWorld', rpc_method_handlers)
+  server.add_generic_rpc_handlers((generic_handler,))

examples/trace/grpc/hello_world_pb2_grpc.py

@@ -0,0 +1,55 @@
+# Copyright 2017, OpenCensus 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.
+
+from concurrent import futures
+import time
+
+import grpc
+
+import hello_world_pb2
+import hello_world_pb2_grpc
+
+from opencensus.trace.ext.grpc import server_interceptor
+from opencensus.trace.samplers import always_on
+from opencensus.trace.exporters import stackdriver_exporter
+
+_ONE_DAY_IN_SECONDS = 60 * 60 * 24
+
+
+class HelloWorld(hello_world_pb2_grpc.HelloWorldServicer):
+
+    def SayHello(self, request, context):
+        return hello_world_pb2.HelloReply(message='Hello, %s!' % request.name)
+
+
+def serve():
+    sampler = always_on.AlwaysOnSampler()
+    exporter = stackdriver_exporter.StackdriverExporter()
+    tracer_interceptor = server_interceptor.OpenCensusServerInterceptor(
+        sampler, exporter)
+    server = grpc.server(
+        futures.ThreadPoolExecutor(max_workers=10),
+        interceptors=(tracer_interceptor,))
+    hello_world_pb2_grpc.add_HelloWorldServicer_to_server(HelloWorld(), 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()