# Copyright 2020 Konstruktor, Inc. 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 functools import reduce
from typing import Any, Union, Callable
from tethys.core.pipes.filters.filter_base import FilterBase
_ALIASES = {
"+": sum,
"*": lambda lst: reduce(lambda x, y: x * y, lst),
"max": max,
"min": min,
}
[docs]class CompositeFilter(FilterBase):
"""
This filter aggregate scores from other filters and calculates a new score using a specific function.
"""
def __init__(self, *filters: FilterBase, function: Union[str, Callable] = "+"):
"""
:param filters: list of the filters
:type filters: FilterBase
:param function: function for calculating an aggregated score.
Available aliases: ["+", "*", "max", "min"].
Default value: "+".
:type function: Union[str, Callable]
"""
self._filters, self._function = (
filters,
_ALIASES[function] if isinstance(function, str) else function,
)
super(CompositeFilter, self).__init__(*filters, function=function)
[docs] def execute(self, data_packet: Any, **kwargs) -> float:
"""
Execute each filter and after execute the function with the :class:`typing.Generator` (that contains the scores) argument.
:param data_packet: any data object
:return: calculated score (:class:`float`)
"""
return self._function(f.execute(data_packet, **kwargs) for f in self._filters)