def load(
cls,
path: Union[Text, Path],
new_config: Optional[Dict] = None,
finetuning_epoch_fraction: float = 1.0,
) -> "PolicyEnsemble":
"""Loads policy and domain specification from disk."""
metadata = cls.load_metadata(path)
cls.ensure_model_compatibility(metadata)
policies = []
for i, policy_name in enumerate(metadata["policy_names"]):
policy_cls = registry.policy_from_module_path(policy_name)
dir_name = f"policy_{i}_{policy_cls.__name__}"
policy_path = os.path.join(path, dir_name)
context = {}
if new_config:
context["should_finetune"] = True
config_for_policy = new_config["policies"][i]
epochs = cls._get_updated_epochs(
policy_cls, config_for_policy, finetuning_epoch_fraction
)
if epochs:
context["epoch_override"] = epochs
if "kwargs" not in rasa.shared.utils.common.arguments_of(policy_cls.load):
if context:
raise UnsupportedDialogueModelError(
f"`{policy_cls.__name__}.{policy_cls.load.__name__}` does not "
f"accept `**kwargs`. Attempting to pass {context} to the "
f"policy. `**kwargs` should be added to all policies by "
f"Rasa Open Source 3.0.0."
)
else:
rasa.shared.utils.io.raise_deprecation_warning(
f"`{policy_cls.__name__}.{policy_cls.load.__name__}` does not "
f"accept `**kwargs`. `**kwargs` are required for contextual "
f"information e.g. the flag `should_finetune`.",
warn_until_version="3.0.0",
)
policy = policy_cls.load(policy_path, **context)
cls._ensure_loaded_policy(policy, policy_cls, policy_name)
policies.append(policy)
ensemble_cls = rasa.shared.utils.common.class_from_module_path(
metadata["ensemble_name"]
)
fingerprints = metadata.get("action_fingerprints", {})
ensemble = ensemble_cls(policies, fingerprints)
return ensemble
def ensure_model_compatibility(metadata, version_to_check=None):
from packaging import version
if version_to_check is None:
version_to_check = rasa.constants.MINIMUM_COMPATIBLE_VERSION
model_version = metadata.get("rasa", "0.0.0")
if version.parse(model_version) < version.parse(version_to_check):
raise UnsupportedDialogueModelError(
"The model version is to old to be "
"loaded by this Rasa Core instance. "
"Either retrain the model, or run with"
"an older version. "
"Model version: {} Instance version: {} "
"Minimal compatible version: {}"
"".format(model_version, rasa.__version__, version_to_check),
model_version)
def load(cls, path: Union[Text, Path], **kwargs: Any) -> "Policy":
"""Loads a policy from path.
Args:
path: Path to load policy from.
Returns:
An instance of `Policy`.
"""
metadata_file = Path(path) / cls._metadata_filename()
if metadata_file.is_file():
data = json.loads(rasa.shared.utils.io.read_file(metadata_file))
if (Path(path) / FEATURIZER_FILE).is_file():
featurizer = TrackerFeaturizer.load(path)
data["featurizer"] = featurizer
data.update(kwargs)
constructor_args = rasa.shared.utils.common.arguments_of(cls)
if "kwargs" not in constructor_args:
if set(data.keys()).issubset(set(constructor_args)):
rasa.shared.utils.io.raise_deprecation_warning(
f"`{cls.__name__}.__init__` does not accept `**kwargs` "
f"This is required for contextual information e.g. the flag "
f"`should_finetune`.",
warn_until_version="3.0.0",
)
else:
raise UnsupportedDialogueModelError(
f"`{cls.__name__}.__init__` does not accept `**kwargs`. "
f"Attempting to pass {data} to the policy. "
f"This argument should be added to all policies by "
f"Rasa Open Source 3.0.0."
)
return cls(**data)
logger.info(
f"Couldn't load metadata for policy '{cls.__name__}'. "
f"File '{metadata_file}' doesn't exist."
)
return cls()