Add Ray client protocol version (#13846)

python/ray/tests/test_client_init.py

@@ -36,6 +36,7 @@ def test_num_clients():
         assert isinstance(info3["ray_version"], str), info3
         assert isinstance(info3["ray_commit"], str), info3
         assert isinstance(info3["python_version"], str), info3
+        assert isinstance(info3["protocol_version"], str), info3
         api3.disconnect()
     finally:
         ray_client_server.shutdown_with_server(server)

python/ray/util/client/server/dataservicer.py

@@ -14,6 +14,10 @@ if TYPE_CHECKING:
 
 logger = logging.getLogger(__name__)
 
+# This version string is incremented to indicate breaking changes in the
+# protocol that require upgrading the client version.
+CURRENT_PROTOCOL_VERSION = "2020-02-01"
+
 
 class DataServicer(ray_client_pb2_grpc.RayletDataStreamerServicer):
     def __init__(self, basic_service: "RayletServicer"):
@@ -73,4 +77,5 @@ class DataServicer(ray_client_pb2_grpc.RayletDataStreamerServicer):
             python_version="{}.{}.{}".format(
                 sys.version_info[0], sys.version_info[1], sys.version_info[2]),
             ray_version=ray.__version__,
-            ray_commit=ray.__commit__)
+            ray_commit=ray.__commit__,
+            protocol_version=CURRENT_PROTOCOL_VERSION)

python/ray/util/client/worker.py

@@ -139,6 +139,7 @@ class Worker:
             "python_version": data.python_version,
             "ray_version": data.ray_version,
             "ray_commit": data.ray_commit,
+            "protocol_version": data.protocol_version,
         }
 
     def get(self, vals, *, timeout: Optional[float] = None) -> Any:

src/ray/protobuf/ray_client.proto

@@ -266,6 +266,8 @@ message ConnectionInfoResponse {
   string ray_commit = 3;
   // The Python version (e.g., "3.7.2").
   string python_version = 4;
+  // The protocol version of the server (e.g., "2020-02-01").
+  string protocol_version = 5;
 }
 
 message DataRequest {