def to_air_checkpoint(self) -> Optional[Checkpoint]:
from ray.tune.trainable.util import TrainableUtil
checkpoint_data = self.dir_or_data
if not checkpoint_data:
return None
if isinstance(checkpoint_data, ray.ObjectRef):
checkpoint_data = ray.get(checkpoint_data)
if isinstance(checkpoint_data, str):
checkpoint_dir = TrainableUtil.find_checkpoint_dir(checkpoint_data)
checkpoint = Checkpoint.from_directory(checkpoint_dir)
elif isinstance(checkpoint_data, bytes):
with tempfile.TemporaryDirectory() as tmpdir:
TrainableUtil.create_from_pickle(checkpoint_data, tmpdir)
# Double wrap in checkpoint so we hold the data in memory and
# can remove the temp directory
checkpoint = Checkpoint.from_dict(
Checkpoint.from_directory(tmpdir).to_dict())
elif isinstance(checkpoint_data, dict):
checkpoint = Checkpoint.from_dict(checkpoint_data)
else:
raise RuntimeError(
f"Unknown checkpoint data type: {type(checkpoint_data)}")
return checkpoint
def restore_from_object(self, obj):
"""Restores training state from a checkpoint object.
These checkpoints are returned from calls to save_to_object().
"""
tmpdir = tempfile.mkdtemp("restore_from_object", dir=self.logdir)
checkpoint_path = TrainableUtil.create_from_pickle(obj, tmpdir)
self.restore(checkpoint_path)
shutil.rmtree(tmpdir)
