content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You 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.
   */
  
  package org.apache.celeborn.plugin.flink.fallback;
  
  import java.util.List;
  import java.util.Optional;
  
  import org.apache.flink.runtime.shuffle.JobShuffleContext;
  
  import org.apache.celeborn.client.LifecycleManager;
  import org.apache.celeborn.common.CelebornConf;
  import org.apache.celeborn.common.exception.CelebornIOException;
  import org.apache.celeborn.common.protocol.FallbackPolicy;
  
  public class ShuffleFallbackPolicyRunner {
  
    private static final List<ShuffleFallbackPolicy> FALLBACK_POLICIES =
        ShuffleFallbackPolicyFactory.getShuffleFallbackPolicies();
  
    public static Optional<ShuffleFallbackPolicy> getActivatedFallbackPolicy(
        JobShuffleContext shuffleContext,
        CelebornConf celebornConf,
        LifecycleManager lifecycleManager)
        throws CelebornIOException {
      Optional<ShuffleFallbackPolicy> fallbackPolicy =
          FALLBACK_POLICIES.stream()
              .filter(
                  shuffleFallbackPolicy ->
                      shuffleFallbackPolicy.needFallback(
                          shuffleContext, celebornConf, lifecycleManager))
              .findFirst();
      if (fallbackPolicy.isPresent()
          && FallbackPolicy.NEVER.equals(celebornConf.flinkShuffleFallbackPolicy())) {
        throw new CelebornIOException(
            "Fallback to flink built-in shuffle implementation is prohibited.");
      }
      return fallbackPolicy;
    }
  }
  