Sanitize argument-free object params before logging

src/lightning/fabric/CHANGELOG.md

@@ -9,6 +9,10 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 
 ### Added
 
+- Enabled consolidating distributed checkpoints through `fabric consolidate` in the new CLI [#19560](https://github.com/Lightning-AI/pytorch-lightning/pull/19560)
+
+- Added object sanitization before logging hyperparameters to WandB and Neptune [#19771](https://github.com/Lightning-AI/pytorch-lightning/pull/19771)
+
 - Enabled consolidating distributed checkpoints through `fabric consolidate` in the new CLI ([#19560](https://github.com/Lightning-AI/pytorch-lightning/pull/19560))
 
 - Added the ability to explicitly mark forward methods in Fabric via `_FabricModule.mark_forward_method()` ([#19690](https://github.com/Lightning-AI/pytorch-lightning/pull/19690))
@@ -17,7 +21,6 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 
 - Added `ModelParallelStrategy` to support 2D parallelism ([#19846](https://github.com/Lightning-AI/pytorch-lightning/pull/19846), [#19852](https://github.com/Lightning-AI/pytorch-lightning/pull/19852), [#19870](https://github.com/Lightning-AI/pytorch-lightning/pull/19870), [#19872](https://github.com/Lightning-AI/pytorch-lightning/pull/19872))
 
-
 ### Changed
 
 - Renamed `lightning run model` to `fabric run` ([#19442](https://github.com/Lightning-AI/pytorch-lightning/pull/19442), [#19527](https://github.com/Lightning-AI/pytorch-lightning/pull/19527))

src/lightning/fabric/utilities/logger.py

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+
+import inspect
 import json
 from argparse import Namespace
 from dataclasses import asdict, is_dataclass
@@ -52,6 +54,10 @@ def _sanitize_callable_params(params: Dict[str, Any]) -> Dict[str, Any]:
     """
 
     def _sanitize_callable(val: Any) -> Any:
+        # If it's a class, return the name; otherwise for a class without any initialization arguments,
+        # the configuration will store an instance of the class, which is not what we want.
+        if inspect.isclass(val):
+            return getattr(val, "__name__", None)
         # Give them one chance to return a value. Don't go rabbit hole of recursive call
         if callable(val):
             try:

tests/tests_fabric/utilities/test_logger.py

@@ -92,7 +92,7 @@ class B:
 
 
 def test_sanitize_callable_params():
-    """Callback function are not serializiable.
+    """Callback functions are not serializable.
 
     Therefore, we get them a chance to return something and if the returned type is not accepted, return None.
 
@@ -104,11 +104,24 @@ def return_something():
     def wrapper_something():
         return return_something
 
+    class Something:
+        def __init__(self):
+            pass
+
+    class SomethingElse:
+        def __init__(self, arg):
+            self.arg = arg
+
+        def __repr__(self):
+            return "SomethingElseElse"
+
     params = Namespace(
         foo="bar",
         something=return_something,
         wrapper_something_wo_name=(lambda: lambda: "1"),
         wrapper_something=wrapper_something,
+        something_class=Something,
+        something_else=SomethingElse,
     )
 
     params = _convert_params(params)
@@ -118,6 +131,8 @@ def wrapper_something():
     assert params["something"] == "something"
     assert params["wrapper_something"] == "wrapper_something"
     assert params["wrapper_something_wo_name"] == "<lambda>"
+    assert params["something_class"] == "Something"
+    assert params["something_else"] == "SomethingElseElse"
 
 
 def test_sanitize_params():