--wip-- [skip ci]

Signed-off-by: Aaron Pham <29749331+aarnphm@users.noreply.github.com>

src/bentoml/_internal/utils/__init__.py

@@ -69,22 +69,31 @@
 _EXPERIMENTAL_APIS: set[str] = set()
 
 
-def _warn_experimental(f: t.Any):
-    api_name = f.__name__ if inspect.isfunction(f) else repr(f)
+def _warn_experimental(api_name: str) -> None:
     if api_name not in _EXPERIMENTAL_APIS:
         _EXPERIMENTAL_APIS.add(api_name)
         msg = "'%s' is an EXPERIMENTAL API and is currently not yet stable. Proceed with caution!"
-        logger = logging.getLogger(f.__module__)
+        logger = logging.getLogger(__name__)
         logger.warning(msg, api_name)
 
 
-def experimental(f: t.Callable[P, t.Any]) -> t.Callable[P, t.Any]:
-    @functools.wraps(f)
-    def wrapper(*args: P.args, **kwargs: P.kwargs) -> t.Any:
-        _warn_experimental(f)
-        return f(*args, **kwargs)
+def experimental(
+    f: t.Callable[P, t.Any] | None = None, *, api_name: str | None = None
+) -> t.Callable[..., t.Any]:
+    if api_name is None:
+        api_name = f.__name__ if inspect.isfunction(f) else repr(f)
 
-    return wrapper
+    def decorator(func: t.Callable[..., t.Any]) -> t.Callable[P, t.Any]:
+        @functools.wraps(func)
+        def wrapper(*args: P.args, **kwargs: P.kwargs) -> t.Any:
+            _warn_experimental(api_name)
+            return func(*args, **kwargs)
+
+        return wrapper
+
+    if f is None:
+        return decorator
+    return decorator(f)
 
 
 def add_experimental_docstring(f: t.Callable[P, t.Any]) -> t.Callable[P, t.Any]:

src/bentoml/metrics.py

@@ -7,6 +7,9 @@
 from simple_di import inject
 from simple_di import Provide
 
+from ._internal.utils import _warn_experimental
+from ._internal.utils import add_experimental_docstring
+
 if TYPE_CHECKING:
     from ._internal.server.metrics.prometheus import PrometheusClient
 
@@ -28,7 +31,11 @@ def __init__(self, attr: t.Any):
         self._args: tuple[t.Any, ...] = ()
         self._kwargs: dict[str, t.Any] = {}
 
+    @add_experimental_docstring
     def __call__(self, *args: t.Any, **kwargs: t.Any) -> t.Any:
+        """
+        Lazily initialize the metrics object.
+        """
         # This is where we lazy load the proxy object.
         self._args = args
         self._kwargs = kwargs