/*

* SPDX-License-Identifier: Apache-2.0

* Copyright 2018-2020 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.

*/

package feast.serving.service;

import feast.proto.serving.ServingAPIProto;

import feast.proto.serving.TransformationServiceAPIProto.TransformFeaturesRequest;

import feast.proto.serving.TransformationServiceAPIProto.TransformFeaturesResponse;

import feast.proto.serving.TransformationServiceAPIProto.ValueType;

import feast.proto.types.ValueProto;

import java.util.List;

import java.util.Set;

import org.apache.commons.lang3.tuple.Pair;

public interface TransformationService {

/**

* Apply on demand transformations for the specified ODFVs.

*

* @param transformFeaturesRequest proto containing the ODFV references and necessary data

* @return a proto object containing the response

*/

TransformFeaturesResponse transformFeatures(TransformFeaturesRequest transformFeaturesRequest);

/**

* Extract the list of on demand feature sources from a list of ODFV references.

*

* @param onDemandFeatureReferences list of ODFV references to be parsed

* @return list of on demand feature sources

*/

List<ServingAPIProto.FeatureReferenceV2> extractOnDemandFeaturesDependencies(

List<ServingAPIProto.FeatureReferenceV2> onDemandFeatureReferences);

/**

* Process a response from the feature transformation server by augmenting the given lists of

* field maps and status maps with the correct fields from the response.

*

* @param transformFeaturesResponse response to be processed

* @param onDemandFeatureViewName name of ODFV to which the response corresponds

* @param onDemandFeatureStringReferences set of all ODFV references that should be kept

* @param responseBuilder {@link ServingAPIProto.GetOnlineFeaturesResponse.Builder}

*/

void processTransformFeaturesResponse(

TransformFeaturesResponse transformFeaturesResponse,

String onDemandFeatureViewName,

Set<String> onDemandFeatureStringReferences,

ServingAPIProto.GetOnlineFeaturesResponse.Builder responseBuilder);

/**

* Serialize data into Arrow IPC format, to be sent to the Python feature transformation server.

*

* @param values list of field maps to be serialized

* @return the data packaged into a ValueType proto object

*/

ValueType serializeValuesIntoArrowIPC(List<Pair<String, List<ValueProto.Value>>> values);

}