# Copyright (c) 2023, 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 typing import Dict
from nvflare.apis.dxo import DXO
from nvflare.apis.fl_component import FLComponent
from nvflare.apis.fl_context import FLContext
[docs]class Assembler(FLComponent, ABC):
"""Assembler class for aggregation functionality
This defines the functionality of assembling the collected submissions
for CollectAndAssembleAggragator
"""
def __init__(self, data_kind: str):
super().__init__()
self.expected_data_kind = data_kind
self.logger.debug(f"expected data kind: {self.expected_data_kind}")
self._collection: dict = {}
[docs] def initialize(self, fl_ctx: FLContext):
pass
@property
def collection(self):
return self._collection
[docs] def get_expected_data_kind(self):
return self.expected_data_kind
[docs] @abstractmethod
def get_model_params(self, dxo: DXO) -> dict:
"""Connects the assembler's _collection with CollectAndAssembleAggregator
Get the collected parameters from the main aggregator
Return:
A dict of parameters needed for further assembling
"""
raise NotImplementedError
[docs] @abstractmethod
def assemble(self, data: Dict[str, dict], fl_ctx: FLContext) -> DXO:
"""Assemble the collected submissions.
This will be specified according to the specific algorithm
E.g. global svm round on the collected local supporting vectors;
global k-means step on the local centroids and counts
Return:
A DXO containing all information ready to be returned to clients
"""
raise NotImplementedError
[docs] def reset(self) -> None:
# Reset parameters for next round,
# This will be performed at the end of each aggregation round,
# it can include, but not limited to, clearing the _collection
self._collection = {}