fix: ensure model starts with publishers/ when users provide resource path from models/

PiperOrigin-RevId: 640914707

Author: Zhenyi Qi

tests/unit/vertexai/test_generative_models.py

@@ -422,24 +422,28 @@ def test_generative_model_constructor_model_name(
             model1._prediction_resource_name
             == project_location_prefix + "publishers/google/models/" + model_name1
         )
+        assert model1._model_name == "publishers/google/models/gemini-pro"
 
         model_name2 = "models/gemini-pro"
         model2 = generative_models.GenerativeModel(model_name2)
         assert (
             model2._prediction_resource_name
             == project_location_prefix + "publishers/google/" + model_name2
         )
+        assert model2._model_name == "publishers/google/models/gemini-pro"
 
         model_name3 = "publishers/some_publisher/models/some_model"
         model3 = generative_models.GenerativeModel(model_name3)
         assert model3._prediction_resource_name == project_location_prefix + model_name3
+        assert model3._model_name == "publishers/some_publisher/models/some_model"
 
         model_name4 = (
             f"projects/{_TEST_PROJECT2}/locations/{_TEST_LOCATION2}/endpoints/endpoint1"
         )
         model4 = generative_models.GenerativeModel(model_name4)
         assert model4._prediction_resource_name == model_name4
         assert _TEST_LOCATION2 in model4._prediction_client._api_endpoint
+        assert model4._model_name == model_name4
 
         with pytest.raises(ValueError):
             generative_models.GenerativeModel("foo/bar/models/gemini-pro")

vertexai/generative_models/_generative_models.py

@@ -110,7 +110,7 @@ def _reconcile_model_name(model_name: str, project: str, location: str) -> str:
     if "/" not in model_name:
         return f"publishers/google/models/{model_name}"
     elif model_name.startswith("models/"):
-        return f"projects/{project}/locations/{location}/publishers/google/{model_name}"
+        return f"publishers/google/{model_name}"
     elif model_name.startswith("publishers/") or model_name.startswith("projects/"):
         return model_name
     else: