Implement python Greeter server.

(assumes that grpcio is installed already)

Author: Nikos Michalakis

examples/helloworld/python/BUILD

@@ -14,3 +14,12 @@ py_binary(
         "//examples/helloworld/proto:py",
     ],
 )
+
+py_binary(
+    name = "greeter_server",
+    srcs = [
+        "greeter_server.py",
+        "//examples/proto:py",
+        "//examples/helloworld/proto:py",
+    ],
+)

examples/helloworld/python/greeter_server.py

@@ -0,0 +1,84 @@
+# Copyright 2015, Google Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+"""The Python implementation of the GRPC helloworld.Greeter server."""
+
+from __future__ import print_function
+
+import grpc
+import time
+
+from concurrent import futures
+from examples.helloworld.proto import helloworld_pb2
+
+_ONE_DAY_IN_SECONDS = 60 * 60 * 24
+
+
+class _GreeterServer(object):
+
+    def __init__(self, greeter_service, server_port):
+        self.server = grpc.server(futures.ThreadPoolExecutor(max_workers=10))
+        helloworld_pb2.add_GreeterServicer_to_server(greeter_service, self.server)
+        self.server.add_insecure_port('[::]:{server_port}'.format(server_port=server_port))
+
+    def start(self):
+        self.server.start()
+
+    def stop(self):
+        self.server.stop(0)
+
+    def await_termination(self):
+        """
+        server.start() doesn't block so we explicitly block here unless someone keyboard-exits us.
+        :return:
+        """
+        try:
+            while True:
+                time.sleep(_ONE_DAY_IN_SECONDS)
+        except KeyboardInterrupt:
+            self.server.stop(0)
+        pass
+
+
+class _GreeterService(helloworld_pb2.GreeterServicer):
+
+    def SayHello(self, hello_request, context):
+        print("Greeter server received: " + hello_request.name)
+        hello_reply = helloworld_pb2.HelloReply()
+        hello_reply.message = 'Hello {name}'.format(name=hello_request.name)
+        return hello_reply
+
+
+def main():
+    greeter_server = _GreeterServer(_GreeterService(), 50051)
+    greeter_server.start()
+    greeter_server.await_termination()
+
+if __name__ == '__main__':
+    main()