Refactor python module structure

slam/slam_servicer.py

@@ -0,0 +1,31 @@
+import slam.SlamController_pb2_grpc as grpc
+import slam.SlamController_pb2 as proto
+import slam.slam_streamer as slam
+from multiprocessing import Process
+
+
+class SlamServicer(grpc.SlamControlServicer):
+    slam_thread = None
+
+    def __init__(self, lidar_connection):
+        print('Servicer initialised')
+        self.slam = slam.SlamStreamer(lidar_connection=lidar_connection)
+
+    def start_map_streaming(self, request, context):
+        print('Received Map Start Streaming Request')
+        if self.slam_thread is None:
+            print('initialising slam_thread')
+            # Don't bother creating and starting slam more than once.
+            self.slam.port = request.port
+            self.slam.map_pixels = request.map_size_pixels
+            self.slam.map_meters = request.map_size_meters
+            self.slam_thread = Process(target=self.slam.start)
+            self.slam_thread.start()
+        return proto.Empty()
+
+    def stop_streaming(self, request, context):
+        if self.slam_thread is not None:
+            self.slam.stop_scanning()
+            self.slam_thread.join()
+            self.slam = None
+        return proto.Empty()