Used oneof in blimp_message.proto

blimp/common/proto/protocol_control.proto

Index: blimp/common/proto/protocol_control.proto
diff --git a/blimp/common/proto/protocol_control.proto b/blimp/common/proto/protocol_control.proto
index 7dd1004490270137fa3ead2a340092cf8658cc8c..3e743a800b19a84e24db837ad537102e314460c7 100644
--- a/blimp/common/proto/protocol_control.proto
+++ b/blimp/common/proto/protocol_control.proto
@@ -20,20 +20,11 @@ message StartConnectionMessage {
 }
 
 message ProtocolControlMessage {
-  enum Type {
-    UNKNOWN = 0;
-
+  oneof connection_message {
     // Client => Server types.
-    START_CONNECTION = 1;
-
-    // Server => Client types will start from 100.
+    StartConnectionMessage start_connection = 41;
 
-    // Bi-directional types.
-    CHECKPOINT_ACK = 200;
+    // Server => Client types.
+    CheckpointAckMessage checkpoint_ack = 42;
   }
-
-  optional Type type = 1;
-
-  optional StartConnectionMessage start_connection = 1001;
-  optional CheckpointAckMessage checkpoint_ack = 1200;
 }