# Copyright (c) 2021, NVIDIA CORPORATION. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# 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.
from abc import ABC, abstractmethod
from nvflare.apis.fl_context import FLContext
from nvflare.app_common.model_desc import ModelDescriptor
from .learnable_persistor import LearnablePersistor
from .model import ModelLearnable
from .persistor_filter import PersistorFilter
[docs]class ModelPersistor(LearnablePersistor, ABC):
def __init__(self, filter_id: str = None):
"""Abstract class.
Implementations will need to implement the `load_model()` and `save_model()`
methods to persist & load the current ModelLearnable.
Args:
filter_id: Optional string that defines a filter component that is applied to prepare the model to be saved,
e.g. for serialization of custom Python objects.
"""
super().__init__()
self.filter_id = filter_id
[docs] def load(self, fl_ctx: FLContext) -> ModelLearnable:
learnable = self.load_model(fl_ctx)
if self.filter_id:
_filter = fl_ctx.get_engine().get_component(self.filter_id)
if not isinstance(_filter, PersistorFilter):
raise ValueError(f"Expected filter to be of type `PersistorFilter` but got {type(filter)}")
learnable = _filter.process_post_load(learnable=learnable, fl_ctx=fl_ctx)
return learnable
[docs] def save(self, learnable: ModelLearnable, fl_ctx: FLContext):
if self.filter_id:
_filter = fl_ctx.get_engine().get_component(self.filter_id)
if not isinstance(_filter, PersistorFilter):
raise ValueError(f"Expected filter to be of type `PersistorFilter` but got {type(filter)}")
learnable = _filter.process_pre_save(learnable=learnable, fl_ctx=fl_ctx)
self.save_model(learnable, fl_ctx)
if self.filter_id:
_filter.process_post_save(learnable=learnable, fl_ctx=fl_ctx)
[docs] def get(self, model_file, fl_ctx: FLContext) -> object:
learnable = self.get_model(model_file, fl_ctx)
if self.filter_id:
_filter = fl_ctx.get_engine().get_component(self.filter_id)
if not isinstance(_filter, PersistorFilter):
raise ValueError(f"Expected filter to be of type `PersistorFilter` but got {type(filter)}")
learnable = _filter.process_post_get(learnable=learnable, fl_ctx=fl_ctx)
return learnable
[docs] @abstractmethod
def load_model(self, fl_ctx: FLContext) -> ModelLearnable:
"""Initialize and load the model.
Args:
fl_ctx: FLContext
Returns:
Model object
"""
pass
[docs] @abstractmethod
def save_model(self, model: ModelLearnable, fl_ctx: FLContext):
"""Persist the model object.
Args:
model: Model object to be saved
fl_ctx: FLContext
"""
pass
[docs] def get_model_inventory(self, fl_ctx: FLContext) -> {str: ModelDescriptor}:
"""Get the model inventory of the ModelPersister.
Args:
fl_ctx: FLContext
Returns: { model_kind: ModelDescriptor }
"""
pass
[docs] def get_model(self, model_file: str, fl_ctx: FLContext) -> ModelLearnable:
pass