Source code for feast.feature

# Copyright 2020 The Feast Authors
#
# 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
#
#     https://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 typing import Dict, Optional

from feast.protos.feast.core.Feature_pb2 import FeatureSpecV2 as FeatureSpecProto
from feast.protos.feast.types.Value_pb2 import ValueType as ValueTypeProto
from feast.value_type import ValueType


[docs]class Feature: """ A Feature represents a class of serveable feature. Args: name: Name of the feature. dtype: The type of the feature, such as string or float. labels (optional): User-defined metadata in dictionary form. """ def __init__( self, name: str, dtype: ValueType, labels: Optional[Dict[str, str]] = None, ): """Creates a Feature object.""" self._name = name if not isinstance(dtype, ValueType): raise ValueError("dtype is not a valid ValueType") if dtype is ValueType.UNKNOWN: raise ValueError(f"dtype cannot be {dtype}") self._dtype = dtype if labels is None: self._labels = dict() else: self._labels = labels def __eq__(self, other): if self.name != other.name or self.dtype != other.dtype: return False return True def __lt__(self, other): return self.name < other.name def __repr__(self): # return string representation of the reference return f"{self.name}-{self.dtype}" def __str__(self): # readable string of the reference return f"Feature<{self.__repr__()}>" @property def name(self): """ Gets the name of this feature. """ return self._name @property def dtype(self) -> ValueType: """ Gets the data type of this feature. """ return self._dtype @property def labels(self) -> Dict[str, str]: """ Gets the labels of this feature. """ return self._labels
[docs] def to_proto(self) -> FeatureSpecProto: """ Converts Feature object to its Protocol Buffer representation. Returns: A FeatureSpecProto protobuf. """ value_type = ValueTypeProto.Enum.Value(self.dtype.name) return FeatureSpecProto( name=self.name, value_type=value_type, tags=self.labels, )
[docs] @classmethod def from_proto(cls, feature_proto: FeatureSpecProto): """ Args: feature_proto: FeatureSpecV2 protobuf object Returns: Feature object """ feature = cls( name=feature_proto.name, dtype=ValueType(feature_proto.value_type), labels=dict(feature_proto.tags), ) return feature