Deprecate `on_configure_sharded_model` callback hook for v1.6 (#11627)

Co-authored-by: Rohit Gupta <rohitgr1998@gmail.com>
Co-authored-by: Danielle Pintz <38207072+daniellepintz@users.noreply.github.com>
Co-authored-by: ananthsub <ananth.subramaniam@gmail.com>
Co-authored-by: Adrian Wälchli <aedu.waelchli@gmail.com>

CHANGELOG.md

@@ -290,6 +290,9 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 - Deprecated function `pytorch_lightning.callbacks.device_stats_monitor.prefix_metric_keys` ([#11254](https://github.com/PyTorchLightning/pytorch-lightning/pull/11254))
 
 
+- Deprecated `on_configure_sharded_model` callback hook in favor of `setup` ([#11627](https://github.com/PyTorchLightning/pytorch-lightning/pull/11627))
+
+
 ### Removed
 
 - Removed deprecated parameter `method` in `pytorch_lightning.utilities.model_helpers.is_overridden` ([#10507](https://github.com/PyTorchLightning/pytorch-lightning/pull/10507))

pytorch_lightning/callbacks/base.py

@@ -57,7 +57,12 @@ class Callback:
         return f"{self.__class__.__qualname__}{repr(kwargs)}"
 
     def on_configure_sharded_model(self, trainer: "pl.Trainer", pl_module: "pl.LightningModule") -> None:
-        """Called before configure sharded model."""
+        r"""
+        .. deprecated:: v1.6
+            This callback hook was deprecated in v1.6 and will be removed in v1.8. Use `setup()` instead.
+
+        Called before configure sharded model.
+        """
 
     def on_before_accelerator_backend_setup(self, trainer: "pl.Trainer", pl_module: "pl.LightningModule") -> None:
         """Called before accelerator is being setup."""

pytorch_lightning/trainer/configuration_validator.py

@@ -57,6 +57,8 @@ def verify_loop_configurations(trainer: "pl.Trainer") -> None:
     _check_on_init_start_end(trainer)
     # TODO: Delete _check_on_hpc_hooks in v1.8
     _check_on_hpc_hooks(model)
+    # TODO: Remove this in v1.8
+    _check_on_configure_sharded_model(trainer)
 
 
 def __verify_train_val_loop_configuration(trainer: "pl.Trainer", model: "pl.LightningModule") -> None:
@@ -322,3 +324,12 @@ def _check_on_hpc_hooks(model: "pl.LightningModule") -> None:
             "Method `LightningModule.on_hpc_load` is deprecated in v1.6 and"
             " will be removed in v1.8. Please use `LightningModule.on_load_checkpoint` instead."
         )
+
+
+def _check_on_configure_sharded_model(trainer: "pl.Trainer") -> None:
+    for callback in trainer.callbacks:
+        if is_overridden(method_name="on_configure_sharded_model", instance=callback):
+            rank_zero_deprecation(
+                "The `on_configure_sharded_model` callback hook was deprecated in"
+                " v1.6 and will be removed in v1.8. Use `setup()` instead."
+            )

tests/deprecated_api/test_remove_1-8.py

@@ -351,3 +351,24 @@ def test_v1_8_0_deprecated_lightning_optimizers():
         match="Trainer.lightning_optimizers` is deprecated in v1.6 and will be removed in v1.8"
     ):
         assert trainer.lightning_optimizers == {}
+
+
+def test_v1_8_0_on_configure_sharded_model(tmpdir):
+    class TestCallback(Callback):
+        def on_configure_sharded_model(self, trainer, model):
+            print("Configuring sharded model")
+
+    model = BoringModel()
+
+    trainer = Trainer(
+        callbacks=[TestCallback()],
+        max_epochs=1,
+        fast_dev_run=True,
+        enable_progress_bar=False,
+        logger=False,
+        default_root_dir=tmpdir,
+    )
+    with pytest.deprecated_call(
+        match="The `on_configure_sharded_model` callback hook was deprecated in v1.6 and will be removed in v1.8."
+    ):
+        trainer.fit(model)