code: /*
   * SPDX-License-Identifier: Apache-2.0
   * Copyright 2018-2019 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 dev.feast;
  
  import feast.proto.serving.ServingAPIProto.FeatureReferenceV2;
  import java.util.List;
  import java.util.stream.Collectors;
  
  @SuppressWarnings("WeakerAccess")
  public class RequestUtil {
  
    /**
     * Create feature references protos from given string feature reference.
     *
     * @param featureRefStrings to create Feature Reference protos from
     * @return List of parsed {@link FeatureReferenceV2} protos
     */
    public static List<FeatureReferenceV2> createFeatureRefs(List<String> featureRefStrings) {
      if (featureRefStrings == null) {
        throw new IllegalArgumentException("FeatureReferences cannot be null");
      }
  
      List<FeatureReferenceV2> featureRefs =
          featureRefStrings.stream().map(RequestUtil::parseFeatureRef).collect(Collectors.toList());
  
      return featureRefs;
    }
  
    /**
     * Parse a feature reference proto builder from the given featureRefString
     *
     * @param featureRefString string feature reference to parse from.
     * @return a parsed {@link FeatureReferenceV2}
     */
    public static FeatureReferenceV2 parseFeatureRef(String featureRefString) {
      featureRefString = featureRefString.trim();
      if (featureRefString.isEmpty()) {
        throw new IllegalArgumentException("Cannot parse a empty feature reference");
      }
      if (featureRefString.contains("/")) {
        throw new IllegalArgumentException(
            String.format(
                "Unsupported feature reference: Specifying project in string"
                    + " Feature References is not longer supported: %s",
                featureRefString));
      }
      if (!featureRefString.contains(":")) {
        throw new IllegalArgumentException(
            String.format(
                "Unsupported feature reference: %s - FeatureTable name and Feature name should be provided in string"
                    + " Feature References, in <featureTableName>:<featureName> format.",
                featureRefString));
      }
  
      String[] featureReferenceParts = featureRefString.split(":");
      FeatureReferenceV2 featureRef =
          FeatureReferenceV2.newBuilder()
              .setFeatureViewName(featureReferenceParts[0])
              .setFeatureName(featureReferenceParts[1])
              .build();
  
      return featureRef;
    }
  }
  