fix: pass hub_arn to get_init_kwargs in _build_for_jumpstart

The _build_for_jumpstart method was not forwarding hub_arn to
get_init_kwargs, causing private hub models to fail during model
creation. Without hub_arn, the SDK could not resolve the correct
account ID in the hub content ARN, resulting in 'hub content not
found' errors for private hubs.

Public hub models are unaffected since hub_arn is None for them.

Author: varunmoris

sagemaker-serve/src/sagemaker/serve/model_builder_servers.py

@@ -867,6 +867,7 @@ def _build_for_jumpstart(self) -> Model:
             model_version=self.model_version or "*",
             region=self.region,
             instance_type=self.instance_type,
+            hub_arn=self.hub_arn,
             tolerate_vulnerable_model=getattr(self, 'tolerate_vulnerable_model', None),
             tolerate_deprecated_model=getattr(self, 'tolerate_deprecated_model', None),
             config_name=getattr(self, 'config_name', None),

sagemaker-serve/tests/unit/test_model_builder_servers_coverage.py

@@ -393,6 +393,68 @@ def test_build_for_jumpstart_passes_config_name(self, mock_prepare, mock_build_d
         call_kwargs = mock_get_kwargs.call_args
         self.assertEqual(call_kwargs.kwargs.get("config_name") or call_kwargs[1].get("config_name"), "lmi-optimized")
 
+    @patch('sagemaker.core.jumpstart.factory.utils.get_init_kwargs')
+    @patch('sagemaker.serve.model_builder.ModelBuilder._build_for_djl_jumpstart')
+    @patch('sagemaker.serve.model_builder.ModelBuilder._prepare_for_mode')
+    def test_build_for_jumpstart_passes_hub_arn(self, mock_prepare, mock_build_djl, mock_get_kwargs):
+        """Test that hub_arn is forwarded to get_init_kwargs for private hub models."""
+        mock_init_kwargs = Mock()
+        mock_init_kwargs.image_uri = "763104351884.dkr.ecr.us-west-2.amazonaws.com/djl-inference:0.21.0-deepspeed0.8.0-cu117"
+        mock_init_kwargs.env = {}
+        mock_get_kwargs.return_value = mock_init_kwargs
+
+        mock_model = Mock(spec=Model)
+        mock_build_djl.return_value = mock_model
+
+        private_hub_arn = "arn:aws:sagemaker:us-west-2:052150106756:hub/MyPrivateHub2"
+
+        builder = ModelBuilder(
+            model="huggingface-vlm-qwen3-5-27b",
+            role_arn=MOCK_ROLE_ARN,
+            sagemaker_session=self.mock_session,
+            mode=Mode.SAGEMAKER_ENDPOINT
+        )
+        builder._optimizing = False
+        builder.hub_arn = private_hub_arn
+
+        builder._build_for_jumpstart()
+
+        mock_get_kwargs.assert_called_once()
+        call_kwargs = mock_get_kwargs.call_args
+        self.assertEqual(
+            call_kwargs.kwargs.get("hub_arn") or call_kwargs[1].get("hub_arn"),
+            private_hub_arn,
+        )
+
+    @patch('sagemaker.core.jumpstart.factory.utils.get_init_kwargs')
+    @patch('sagemaker.serve.model_builder.ModelBuilder._build_for_djl_jumpstart')
+    @patch('sagemaker.serve.model_builder.ModelBuilder._prepare_for_mode')
+    def test_build_for_jumpstart_hub_arn_none_for_public_hub(self, mock_prepare, mock_build_djl, mock_get_kwargs):
+        """Test that hub_arn is None for public hub models (no regression)."""
+        mock_init_kwargs = Mock()
+        mock_init_kwargs.image_uri = "763104351884.dkr.ecr.us-west-2.amazonaws.com/djl-inference:0.21.0-deepspeed0.8.0-cu117"
+        mock_init_kwargs.env = {}
+        mock_get_kwargs.return_value = mock_init_kwargs
+
+        mock_model = Mock(spec=Model)
+        mock_build_djl.return_value = mock_model
+
+        builder = ModelBuilder(
+            model="meta-textgeneration-llama-3-3-70b-instruct",
+            role_arn=MOCK_ROLE_ARN,
+            sagemaker_session=self.mock_session,
+            mode=Mode.SAGEMAKER_ENDPOINT
+        )
+        builder._optimizing = False
+
+        builder._build_for_jumpstart()
+
+        mock_get_kwargs.assert_called_once()
+        call_kwargs = mock_get_kwargs.call_args
+        self.assertIsNone(
+            call_kwargs.kwargs.get("hub_arn") or call_kwargs[1].get("hub_arn"),
+        )
+
     @patch('sagemaker.core.jumpstart.factory.utils.get_init_kwargs')
     @patch('sagemaker.serve.model_builder.ModelBuilder._build_for_tgi_jumpstart')
     @patch('sagemaker.serve.model_builder.ModelBuilder._prepare_for_mode')