common/src/test/java/org/apache/nemo/common/ir/LoopVertexTest.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
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 * 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
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 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
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package org.apache.nemo.common.ir;

import org.apache.nemo.common.Pair;
import org.apache.nemo.common.dag.DAGBuilder;
import org.apache.nemo.common.ir.edge.IREdge;
import org.apache.nemo.common.ir.edge.executionproperty.CommunicationPatternProperty;
import org.apache.nemo.common.ir.vertex.IRVertex;
import org.apache.nemo.common.ir.vertex.LoopVertex;
import org.apache.nemo.common.ir.vertex.OperatorVertex;
import org.apache.nemo.common.test.EmptyComponents;
import org.junit.Before;
import org.junit.Test;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import static org.junit.Assert.assertEquals;

/**
 * Tests for {@link LoopVertex}.
 */
public class LoopVertexTest {
  private final LoopVertex loopVertex = new LoopVertex("fakeTransform");
  private IRDAG originalDAG;
  private IRDAG newDAG;

  private final IRVertex source = new EmptyComponents.EmptySourceVertex<>("Source");
  private final IRVertex map1 = new OperatorVertex(new EmptyComponents.EmptyTransform("MapElements"));
  private final IRVertex groupByKey = new OperatorVertex(new EmptyComponents.EmptyTransform("GroupByKey"));
  private final IRVertex combine = new OperatorVertex(new EmptyComponents.EmptyTransform("Combine"));
  private final IRVertex map2 = new OperatorVertex(new EmptyComponents.EmptyTransform("map2"));

  @Before
  public void setUp() {
    final DAGBuilder<IRVertex, IREdge> loopDAGBuilder = loopVertex.getBuilder();
    final DAGBuilder<IRVertex, IREdge> builder = new DAGBuilder<>();

    loopDAGBuilder.addVertex(map1).addVertex(groupByKey).addVertex(combine).addVertex(map2)
      .connectVertices(new IREdge(CommunicationPatternProperty.Value.SHUFFLE, map1, groupByKey))
      .connectVertices(new IREdge(CommunicationPatternProperty.Value.ONE_TO_ONE, groupByKey, combine))
      .connectVertices(new IREdge(CommunicationPatternProperty.Value.ONE_TO_ONE, combine, map2));
    loopVertex.addDagIncomingEdge(new IREdge(CommunicationPatternProperty.Value.ONE_TO_ONE, source, map1));
    loopVertex.addIterativeIncomingEdge(new IREdge(CommunicationPatternProperty.Value.ONE_TO_ONE, map2, map1));

    originalDAG = new IRDAG(builder.addVertex(source).addVertex(map1).addVertex(groupByKey).addVertex(combine).addVertex(map2)
      .connectVertices(new IREdge(CommunicationPatternProperty.Value.ONE_TO_ONE, source, map1))
      .connectVertices(new IREdge(CommunicationPatternProperty.Value.SHUFFLE, map1, groupByKey))
      .connectVertices(new IREdge(CommunicationPatternProperty.Value.ONE_TO_ONE, groupByKey, combine))
      .connectVertices(new IREdge(CommunicationPatternProperty.Value.ONE_TO_ONE, combine, map2))
      .build());
  }

  @Test
  public void testDAG() {
    assertEquals(originalDAG.getTopologicalSort().size() - 1, loopVertex.getDAG().getTopologicalSort().size());
    // zip vertices
    final Iterator<IRVertex> vertices1 = originalDAG.getTopologicalSort().iterator();
    vertices1.next();
    final Iterator<IRVertex> vertices2 = loopVertex.getDAG().getTopologicalSort().iterator();
    final List<Pair<IRVertex, IRVertex>> list = new ArrayList<>();
    while (vertices1.hasNext() && vertices2.hasNext()) {
      list.add(Pair.of(vertices1.next(), vertices2.next()));
    }
    list.forEach(irVertexPair -> {
      assertEquals(irVertexPair.left().getExecutionProperties(), irVertexPair.right().getExecutionProperties());
      assertEquals(originalDAG.getOutgoingEdgesOf(irVertexPair.left()).size(),
        loopVertex.getDAG().getOutgoingEdgesOf(irVertexPair.right()).size());
    });

    assertEquals(source, loopVertex.getDagIncomingEdges().values().iterator().next().iterator().next().getSrc());
    assertEquals(map1, loopVertex.getDagIncomingEdges().values().iterator().next().iterator().next().getDst());
  }

  @Test
  public void testIterationTermination() {
    final LoopVertex loopVertexClone = loopVertex.getClone();
    final DAGBuilder<IRVertex, IREdge> builder = new DAGBuilder<>();
    builder.addVertex(source);

    assertEquals(false, loopVertexClone.loopTerminationConditionMet());
    assertEquals(true, loopVertexClone.unRollIteration(builder).loopTerminationConditionMet());

    loopVertexClone.setTerminationCondition((i) -> true);
    assertEquals(true, loopVertexClone.loopTerminationConditionMet());
  }
}