fix(core): detect bundled SDK via version stamp

Author: nvasiu

packages/aws-durable-execution-sdk-python/src/aws_durable_execution_sdk_python/lambda_service.py

@@ -38,13 +38,9 @@
 logger = logging.getLogger(__name__)
 
 
-def _is_in_var_dir(module_file: str = __file__) -> bool:
-    """Return True if this SDK is installed under /var/lang/.
-
-    Lambda bundled Python runtimes install packages at
-    /var/lang/lib/pythonX.Y/site-packages/.
-    """
-    return module_file.startswith("/var/lang/")
+def _is_bundled(version: str) -> bool:
+    """True if the managed runtime stamped a +bundled label onto this install."""
+    return version.endswith("+bundled")
 
 
 # region model
@@ -1218,7 +1214,7 @@ def initialize_client(cls) -> LambdaClient:
                 config=Config(
                     connect_timeout=5,
                     read_timeout=50,
-                    user_agent_extra=f"aws-durable-execution-sdk-python/{__version__}{'-bundled' if _is_in_var_dir() else ''}",
+                    user_agent_extra=f"aws-durable-execution-sdk-python/{__version__.removesuffix('+bundled')}{'-bundled' if _is_bundled(__version__) else ''}",
                 ),
             )
         return cls(client=cls._cached_boto_client)

packages/aws-durable-execution-sdk-python/tests/lambda_service_test.py

@@ -40,7 +40,7 @@
     TimestampConverter,
     WaitDetails,
     WaitOptions,
-    _is_in_var_dir,
+    _is_bundled,
 )
 
 
@@ -2226,14 +2226,14 @@ def test_lambda_client_initialize_client_no_endpoint(
 
 
 @patch(
-    "aws_durable_execution_sdk_python.lambda_service._is_in_var_dir",
+    "aws_durable_execution_sdk_python.lambda_service._is_bundled",
     return_value=True,
 )
 @patch("boto3.client")
 def test_lambda_client_user_agent_runtime_bundled(
-    mock_boto_client, _mock_is_in_var_dir, reset_lambda_client_cache
+    mock_boto_client, _mock_is_bundled, reset_lambda_client_cache
 ):
-    """user_agent_extra includes -bundled when SDK is in /var/lang/."""
+    """user_agent_extra includes -bundled when the +bundled stamp is present."""
     mock_client = Mock()
     mock_boto_client.return_value = mock_client
 
@@ -2243,56 +2243,81 @@ def test_lambda_client_user_agent_runtime_bundled(
     config = call_args[1]["config"]
     assert (
         config.user_agent_extra
-        == f"aws-durable-execution-sdk-python/{__version__}-bundled"
+        == f"aws-durable-execution-sdk-python/{__version__.split('+')[0]}-bundled"
     )
     assert isinstance(client, LambdaClient)
 
 
 @patch(
-    "aws_durable_execution_sdk_python.lambda_service._is_in_var_dir",
+    "aws_durable_execution_sdk_python.lambda_service._is_bundled",
     return_value=False,
 )
 @patch("boto3.client")
 def test_lambda_client_user_agent_not_runtime_bundled(
-    mock_boto_client, _mock_is_in_var_dir, reset_lambda_client_cache
+    mock_boto_client, _mock_is_bundled, reset_lambda_client_cache
 ):
-    """user_agent_extra omits -bundled when SDK is not in /var/lang."""
+    """user_agent_extra omits -bundled when the +bundled stamp is absent."""
     mock_client = Mock()
     mock_boto_client.return_value = mock_client
 
     client = LambdaClient.initialize_client()
 
     call_args = mock_boto_client.call_args
     config = call_args[1]["config"]
-    assert config.user_agent_extra == f"aws-durable-execution-sdk-python/{__version__}"
+    assert (
+        config.user_agent_extra
+        == f"aws-durable-execution-sdk-python/{__version__.split('+')[0]}"
+    )
     assert isinstance(client, LambdaClient)
 
 
+@patch("aws_durable_execution_sdk_python.lambda_service.__version__", "2.0.0+acme.1")
+@patch("boto3.client")
+def test_lambda_client_user_agent_preserves_local_version_label(
+    mock_boto_client, reset_lambda_client_cache
+):
+    """A non-bundled local version label is kept intact in the user agent."""
+    mock_boto_client.return_value = Mock()
+
+    LambdaClient.initialize_client()
+
+    config = mock_boto_client.call_args[1]["config"]
+    assert config.user_agent_extra == "aws-durable-execution-sdk-python/2.0.0+acme.1"
+
+
+@patch("aws_durable_execution_sdk_python.lambda_service.__version__", "2.0.0+bundled")
+@patch("boto3.client")
+def test_lambda_client_user_agent_strips_bundled_suffix(
+    mock_boto_client, reset_lambda_client_cache
+):
+    """The +bundled stamp is stripped from the version and reported as -bundled."""
+    mock_boto_client.return_value = Mock()
+
+    LambdaClient.initialize_client()
+
+    config = mock_boto_client.call_args[1]["config"]
+    assert config.user_agent_extra == "aws-durable-execution-sdk-python/2.0.0-bundled"
+
+
 @pytest.mark.parametrize(
-    "path,expected",
+    "version,expected",
     [
-        # Lambda bundled runtime site-packages
-        (
-            "/var/lang/lib/python3.13/site-packages/aws_durable_execution_sdk_python/lambda_service.py",
-            True,
-        ),
-        (
-            "/var/lang/lib/python3.12/site-packages/aws_durable_execution_sdk_python/lambda_service.py",
-            True,
-        ),
-        # Customer deployment package
-        ("/var/task/aws_durable_execution_sdk_python/lambda_service.py", False),
-        # Lambda Layer
-        ("/opt/python/aws_durable_execution_sdk_python/lambda_service.py", False),
-        # Trailing-slash guard: /var/langsurprise must not match
-        ("/var/langsurprise/lib/python3.13/site-packages/x.py", False),
-        # Local dev
-        ("/Users/me/project/.venv/lib/python3.12/site-packages/x.py", False),
+        # Managed-runtime stamp
+        ("1.7.0+bundled", True),
+        ("1.7.0.post0+bundled", True),
+        # Public PyPI installs never carry the local label
+        ("1.7.0", False),
+        ("1.7.0.post0", False),
+        # A different local label must not match
+        ("1.7.0+local", False),
+        # A label beginning with 'bundled' must not match, only the exact suffix
+        ("1.7.0+bundleddebug", False),
+        ("1.7.0+bundled.1", False),
         ("", False),
     ],
 )
-def test_is_in_var_dir(path, expected):
-    assert _is_in_var_dir(path) is expected
+def test_is_bundled(version, expected):
+    assert _is_bundled(version) is expected
 
 
 def test_lambda_client_checkpoint_with_non_none_client_token():