consolidate callbacks and hooks (#950)

* consolidate callbacks and hooks

* ensure callbacks recieve proper arg types

* remove model from init callback events

* clean up early stopping event

* update changelog

* remove on_fit_start and on_fit_end

* fix args for on_init_start and on_init_end

* handle case where early stopping is not used

* show all callback methods

* wrap checkpoint callback logic into proper class

* fix check for main process in checkpoint callback

* move callbacks test to separate file

* refactor arg checks

* get model and call hook on same line

* define trainer_options dict in one call

* add more asserts to callback test

tests/trainer/test_callbacks.py

@@ -0,0 +1,153 @@
+import tests.models.utils as tutils
+from pytorch_lightning import Trainer, LightningModule
+from tests.models import (
+    TestModelBase,
+    LightTrainDataloader,
+    LightValidationMixin,
+    LightTestMixin
+)
+
+from pytorch_lightning import Callback
+
+
+def test_trainer_callback_system(tmpdir):
+    """Test the callback system."""
+
+    class CurrentTestModel(
+        LightTrainDataloader,
+        LightTestMixin,
+        LightValidationMixin,
+        TestModelBase,
+    ):
+        pass
+
+    hparams = tutils.get_hparams()
+    model = CurrentTestModel(hparams)
+
+    def _check_args(trainer, pl_module):
+        assert isinstance(trainer, Trainer)
+        assert isinstance(pl_module, LightningModule)
+
+    class TestCallback(Callback):
+        def __init__(self):
+            super().__init__()
+            self.on_init_start_called = False
+            self.on_init_end_called = False
+            self.on_epoch_start_called = False
+            self.on_epoch_end_called = False
+            self.on_batch_start_called = False
+            self.on_batch_end_called = False
+            self.on_train_start_called = False
+            self.on_train_end_called = False
+            self.on_validation_start_called = False
+            self.on_validation_end_called = False
+            self.on_test_start_called = False
+            self.on_test_end_called = False
+
+        def on_init_start(self, trainer):
+            assert isinstance(trainer, Trainer)
+            self.on_init_start_called = True
+
+        def on_init_end(self, trainer):
+            assert isinstance(trainer, Trainer)
+            self.on_init_end_called = True
+
+        def on_epoch_start(self, trainer, pl_module):
+            _check_args(trainer, pl_module)
+            self.on_epoch_start_called = True
+
+        def on_epoch_end(self, trainer, pl_module):
+            _check_args(trainer, pl_module)
+            self.on_epoch_end_called = True
+
+        def on_batch_start(self, trainer, pl_module):
+            _check_args(trainer, pl_module)
+            self.on_batch_start_called = True
+
+        def on_batch_end(self, trainer, pl_module):
+            _check_args(trainer, pl_module)
+            self.on_batch_end_called = True
+
+        def on_train_start(self, trainer, pl_module):
+            _check_args(trainer, pl_module)
+            self.on_train_start_called = True
+
+        def on_train_end(self, trainer, pl_module):
+            _check_args(trainer, pl_module)
+            self.on_train_end_called = True
+
+        def on_validation_start(self, trainer, pl_module):
+            _check_args(trainer, pl_module)
+            self.on_validation_start_called = True
+
+        def on_validation_end(self, trainer, pl_module):
+            _check_args(trainer, pl_module)
+            self.on_validation_end_called = True
+
+        def on_test_start(self, trainer, pl_module):
+            _check_args(trainer, pl_module)
+            self.on_test_start_called = True
+
+        def on_test_end(self, trainer, pl_module):
+            _check_args(trainer, pl_module)
+            self.on_test_end_called = True
+
+    test_callback = TestCallback()
+
+    trainer_options = {
+        'callbacks': [test_callback],
+        'max_epochs': 1,
+        'val_percent_check': 0.1,
+        'train_percent_check': 0.2,
+        'show_progress_bar': False
+    }
+
+    assert not test_callback.on_init_start_called
+    assert not test_callback.on_init_end_called
+    assert not test_callback.on_epoch_start_called
+    assert not test_callback.on_epoch_start_called
+    assert not test_callback.on_batch_start_called
+    assert not test_callback.on_batch_end_called
+    assert not test_callback.on_train_start_called
+    assert not test_callback.on_train_end_called
+    assert not test_callback.on_validation_start_called
+    assert not test_callback.on_validation_end_called
+    assert not test_callback.on_test_start_called
+    assert not test_callback.on_test_end_called
+
+    # fit model
+    trainer = Trainer(**trainer_options)
+
+    assert trainer.callbacks[0] == test_callback
+    assert test_callback.on_init_start_called
+    assert test_callback.on_init_end_called
+    assert not test_callback.on_epoch_start_called
+    assert not test_callback.on_epoch_start_called
+    assert not test_callback.on_batch_start_called
+    assert not test_callback.on_batch_end_called
+    assert not test_callback.on_train_start_called
+    assert not test_callback.on_train_end_called
+    assert not test_callback.on_validation_start_called
+    assert not test_callback.on_validation_end_called
+    assert not test_callback.on_test_start_called
+    assert not test_callback.on_test_end_called
+
+    trainer.fit(model)
+
+    assert test_callback.on_init_start_called
+    assert test_callback.on_init_end_called
+    assert test_callback.on_epoch_start_called
+    assert test_callback.on_epoch_start_called
+    assert test_callback.on_batch_start_called
+    assert test_callback.on_batch_end_called
+    assert test_callback.on_train_start_called
+    assert test_callback.on_train_end_called
+    assert test_callback.on_validation_start_called
+    assert test_callback.on_validation_end_called
+    assert not test_callback.on_test_start_called
+    assert not test_callback.on_test_end_called
+
+    trainer.test()
+
+    assert test_callback.on_test_start_called
+    assert test_callback.on_test_end_called

tests/trainer/test_trainer.py

@@ -600,122 +600,3 @@ def test_testpass_overrides(tmpdir):
 
     model = LightningTestModel(hparams)
     Trainer().test(model)
-
-
-def test_trainer_callback_system(tmpdir):
-    """Test the callback system."""
-
-    class CurrentTestModel(
-        LightTrainDataloader,
-        LightTestMixin,
-        LightValidationMixin,
-        TestModelBase,
-    ):
-        pass
-
-    hparams = tutils.get_hparams()
-    model = CurrentTestModel(hparams)
-
-    class TestCallback(Callback):
-        def __init__(self):
-            super().__init__()
-            self.on_init_start_called = False
-            self.on_init_end_called = False
-            self.on_fit_start_called = False
-            self.on_fit_end_called = False
-            self.on_epoch_start_called = False
-            self.on_epoch_end_called = False
-            self.on_batch_start_called = False
-            self.on_batch_end_called = False
-            self.on_train_start_called = False
-            self.on_train_end_called = False
-            self.on_validation_start_called = False
-            self.on_validation_end_called = False
-            self.on_test_start_called = False
-            self.on_test_end_called = False
-
-        def on_init_start(self, trainer):
-            self.on_init_start_called = True
-
-        def on_init_end(self, trainer):
-            self.on_init_end_called = True
-
-        def on_fit_start(self, trainer, pl_module):
-            self.on_fit_start_called = True
-
-        def on_fit_end(self, trainer, pl_module):
-            self.on_fit_end_called = True
-
-        def on_epoch_start(self, trainer, pl_module):
-            self.on_epoch_start_called = True
-
-        def on_epoch_end(self, trainer, pl_module):
-            self.on_epoch_end_called = True
-
-        def on_batch_start(self, trainer, pl_module):
-            self.on_batch_start_called = True
-
-        def on_batch_end(self, trainer, pl_module):
-            self.on_batch_end_called = True
-
-        def on_train_start(self, trainer, pl_module):
-            self.on_train_start_called = True
-
-        def on_train_end(self, trainer, pl_module):
-            self.on_train_end_called = True
-
-        def on_validation_start(self, trainer, pl_module):
-            self.on_validation_start_called = True
-
-        def on_validation_end(self, trainer, pl_module):
-            self.on_validation_end_called = True
-
-        def on_test_start(self, trainer, pl_module):
-            self.on_test_start_called = True
-
-        def on_test_end(self, trainer, pl_module):
-            self.on_test_end_called = True
-
-    test_callback = TestCallback()
-
-    trainer_options = {}
-    trainer_options['callbacks'] = [test_callback]
-    trainer_options['max_epochs'] = 1
-    trainer_options['val_percent_check'] = 0.1
-    trainer_options['train_percent_check'] = 0.2
-    trainer_options['show_progress_bar'] = False
-
-    assert not test_callback.on_init_start_called
-    assert not test_callback.on_init_end_called
-
-    # fit model
-    trainer = Trainer(**trainer_options)
-
-    assert trainer.callbacks[0] == test_callback
-    assert test_callback.on_init_start_called
-    assert test_callback.on_init_end_called
-    assert not test_callback.on_fit_start_called
-    assert not test_callback.on_fit_start_called
-
-    trainer.fit(model)
-
-    assert test_callback.on_fit_start_called
-    assert test_callback.on_fit_end_called
-    assert test_callback.on_epoch_start_called
-    assert test_callback.on_epoch_start_called
-    assert test_callback.on_batch_start_called
-    assert test_callback.on_batch_end_called
-    assert test_callback.on_train_start_called
-    assert test_callback.on_train_end_called
-    assert test_callback.on_validation_start_called
-    assert test_callback.on_validation_end_called
-    assert not test_callback.on_test_start_called
-    assert not test_callback.on_test_end_called
-
-    trainer.test()
-
-    assert test_callback.on_test_start_called
-    assert test_callback.on_test_end_called
-
-# if __name__ == '__main__':
-#     pytest.main([__file__])