websockets transport - optional variables and operation name

gql/transport/websockets.py

@@ -243,16 +243,14 @@ async def _send_query(
         query_id = self.next_query_id
         self.next_query_id += 1
 
+        payload: Dict[str, Any] = {"query": print_ast(document)}
+        if variable_values:
+            payload["variables"] = variable_values
+        if operation_name:
+            payload["operationName"] = operation_name
+
         query_str = json.dumps(
-            {
-                "id": str(query_id),
-                "type": "start",
-                "payload": {
-                    "variables": variable_values or {},
-                    "operationName": operation_name or "",
-                    "query": print_ast(document),
-                },
-            }
+            {"id": str(query_id), "type": "start", "payload": payload}
         )
 
         await self._send(query_str)

tests/test_websocket_subscription.py

@@ -320,6 +320,34 @@ async def test_websocket_subscription_slow_consumer(
     assert count == -1
 
 
+@pytest.mark.asyncio
+@pytest.mark.parametrize("server", [server_countdown], indirect=True)
+@pytest.mark.parametrize("subscription_str", [countdown_subscription_str])
+async def test_websocket_subscription_with_operation_name(
+    event_loop, client_and_server, subscription_str
+):
+
+    session, server = client_and_server
+
+    count = 10
+    subscription = gql(subscription_str.format(count=count))
+
+    async for result in session.subscribe(
+        subscription, operation_name="CountdownSubscription"
+    ):
+
+        number = result["number"]
+        print(f"Number received: {number}")
+
+        assert number == count
+        count -= 1
+
+    assert count == -1
+
+    # Check that the query contains the operationName
+    assert '"operationName": "CountdownSubscription"' in logged_messages[0]
+
+
 WITH_KEEPALIVE = True