initial files to support grpc server/client

.gitignore

@@ -17,6 +17,10 @@ configure
 debian
 stamp-h1
 
+# generated protobuf files
+daemon/core/grpc/core_pb2.py
+daemon/core/grpc/core_pb2_grpc.py
+
 # python build directory
 dist
 

daemon/core/grpc/client.py

@@ -0,0 +1,38 @@
+from __future__ import print_function
+import logging
+from contextlib import contextmanager
+
+import grpc
+
+import core_pb2
+import core_pb2_grpc
+
+
+class CoreApiClient(object):
+    def __init__(self, address="localhost:50051"):
+        self.address = address
+        self.stub = None
+
+    def get_sessions(self):
+        return self.stub.GetSessions(core_pb2.SessionsRequest())
+
+    @contextmanager
+    def connect(self):
+        channel = grpc.insecure_channel(self.address)
+        try:
+            self.stub = core_pb2_grpc.CoreApiStub(channel)
+            yield channel
+        finally:
+            channel.close()
+
+
+def main():
+    client = CoreApiClient()
+    with client.connect():
+        response = client.get_sessions()
+        print("core client received: %s" % response)
+
+
+if __name__ == "__main__":
+    logging.basicConfig()
+    main()

daemon/core/grpc/server.py

@@ -0,0 +1,37 @@
+from concurrent import futures
+import time
+import logging
+
+import grpc
+
+import core_pb2
+import core_pb2_grpc
+
+_ONE_DAY_IN_SECONDS = 60 * 60 * 24
+
+
+class CoreApiServer(core_pb2_grpc.CoreApiServicer):
+
+    def GetSessions(self, request, context):
+        response = core_pb2.SessionsResponse()
+        session = response.sessions.add()
+        session.id = 1
+        return response
+
+
+def main():
+    server = grpc.server(futures.ThreadPoolExecutor(max_workers=10))
+    core_pb2_grpc.add_CoreApiServicer_to_server(CoreApiServer(), 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__":
+    logging.basicConfig()
+    main()

daemon/proto/core.proto

@@ -0,0 +1,18 @@
+syntax = "proto3";
+
+package core;
+
+service CoreApi {
+  rpc GetSessions (SessionsRequest) returns (SessionsResponse) {}
+}
+
+message SessionsRequest {
+}
+
+message SessionsResponse {
+  repeated Session sessions = 1;
+}
+
+message Session {
+  int32 id = 1;
+}