Fix sgl-router silently parse selector wrongly causing OME fail to discover pods (#14359)

sgl-router/bindings/python/sglang_router/router_args.py

@@ -718,6 +718,10 @@ class RouterArgs:
         if not selector_list:
             return {}
 
+        # Support `- --selector\n- a=b c=d` case
+        if len(selector_list) == 1 and (" " in selector_list[0]):
+            selector_list = selector_list[0].split(" ")
+
         selector = {}
         for item in selector_list:
             if "=" in item:

sgl-router/py_test/unit/test_arg_parser.py

@@ -476,7 +476,7 @@ class TestParseRouterArgs:
 
     def test_parse_service_discovery_args(self):
         """Test parsing service discovery arguments."""
-        args = [
+        args_a = [
             "--service-discovery",
             "--selector",
             "app=worker",
@@ -486,7 +486,18 @@ class TestParseRouterArgs:
             "--service-discovery-namespace",
             "default",
         ]
+        args_b = [
+            "--service-discovery",
+            "--selector",
+            # OME has this style
+            "app=worker env=prod",
+            "--service-discovery-port",
+            "8080",
+            "--service-discovery-namespace",
+            "default",
+        ]
 
+        for args in [args_a, args_b]:
             router_args = parse_router_args(args)
 
             assert router_args.service_discovery is True