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.beam.sdk.extensions.euphoria.core.client.operator;
  
  import static java.util.Objects.requireNonNull;
  
  import java.util.Optional;
  import java.util.concurrent.atomic.AtomicReference;
  import org.apache.beam.sdk.Pipeline;
  import org.apache.beam.sdk.extensions.euphoria.core.client.operator.base.Operator;
  import org.apache.beam.sdk.extensions.euphoria.core.client.type.TypeAwareness;
  import org.apache.beam.sdk.extensions.euphoria.core.translate.EuphoriaOptions;
  import org.apache.beam.sdk.extensions.euphoria.core.translate.OperatorTransform;
  import org.apache.beam.sdk.extensions.euphoria.core.translate.OperatorTranslator;
  import org.apache.beam.sdk.extensions.euphoria.core.translate.TranslatorProvider;
  import org.apache.beam.sdk.extensions.kryo.KryoCoder;
  import org.apache.beam.sdk.options.PipelineOptions;
  import org.apache.beam.sdk.options.PipelineOptionsFactory;
  import org.apache.beam.sdk.runners.TransformHierarchy;
  import org.apache.beam.sdk.testing.TestPipeline;
  import org.apache.beam.sdk.transforms.Create;
  import org.apache.beam.sdk.values.PCollection;
  import org.apache.beam.sdk.values.PValue;
  import org.apache.beam.sdk.values.TypeDescriptor;
  
  /** Utility class for easier creating input data sets for operator testing. */
  public class TestUtils {
  
    private static class PrimitiveOutputTranslatorProvider implements TranslatorProvider {
  
      @Override
      public <InputT, OutputT, OperatorT extends Operator<OutputT>>
          Optional<OperatorTranslator<InputT, OutputT, OperatorT>> findTranslator(
              OperatorT operator) {
        return Optional.of(
            (op, inputs) ->
                PCollection.<OutputT>createPrimitiveOutputInternal(
                        inputs.getPipeline(),
                        inputs.get(0).getWindowingStrategy(),
                        inputs.get(0).isBounded(),
                        null)
                    .setTypeDescriptor(TypeAwareness.orObjects(operator.getOutputType())));
      }
    }
  
    public static TestPipeline createTestPipeline() {
      final PipelineOptions pipelineOptions = PipelineOptionsFactory.create();
      pipelineOptions
          .as(EuphoriaOptions.class)
          .setTranslatorProvider(new PrimitiveOutputTranslatorProvider());
      final TestPipeline testPipeline = TestPipeline.fromOptions(pipelineOptions);
      testPipeline
          .getCoderRegistry()
          .registerCoderForClass(Object.class, KryoCoder.of(pipelineOptions));
      return testPipeline;
    }
  
    public static <T> PCollection<T> createMockDataset(TypeDescriptor<T> typeDescriptor) {
      return createMockDataset(createTestPipeline(), typeDescriptor);
    }
  
    public static <T> PCollection<T> createMockDataset(
        Pipeline pipeline, TypeDescriptor<T> typeDescriptor) {
      return pipeline.apply(Create.empty(typeDescriptor));
    }
  
    /**
     * Get an {@link Operator} that produced a given {@link PCollection}.
     *
     * @param pCollection pCollection to find producer for
     * @param <T> type of produced data
     * @return producer
     */
    public static <T> Operator<T> getProducer(PCollection<T> pCollection) {
      final AtomicReference<Operator<T>> operator = new AtomicReference<>();
      pCollection
          .getPipeline()
          .traverseTopologically(
              new Pipeline.PipelineVisitor() {
  
                @Override
                public void enterPipeline(Pipeline p) {
                  // noop
                }
  
                @Override
                public CompositeBehavior enterCompositeTransform(TransformHierarchy.Node node) {
                  if (node.getTransform() instanceof OperatorTransform) {
                    // we do not want to expand euphoria transforms
                    return CompositeBehavior.DO_NOT_ENTER_TRANSFORM;
                  }
                  return CompositeBehavior.ENTER_TRANSFORM;
                }
  
                @Override
                public void leaveCompositeTransform(TransformHierarchy.Node node) {
                  // noop
                }
  
                @Override
                public void visitPrimitiveTransform(TransformHierarchy.Node node) {
                  // noop
                }
  
                @Override
                public void visitValue(PValue value, TransformHierarchy.Node producer) {
                  if (value.equals(pCollection)) {
                    @SuppressWarnings("unchecked")
                    OperatorTransform<?, T, Operator<T>> transform =
                        requireNonNull((OperatorTransform) producer.getTransform());
                    operator.set(transform.getOperator());
                  }
                }
  
                @Override
                public void leavePipeline(Pipeline pipeline) {
                  // noop
                }
              });
      return requireNonNull(
          operator.get(), "Can not find producer for PCollection [" + pCollection.getName() + "].");
    }
  }
  