ScorerTest.java

// Copyright 2016 Twitter. All rights reserved.
//
// 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
//
//    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 com.twitter.heron.packing.builder;

import org.junit.Before;
import org.junit.Test;

import com.twitter.heron.common.basics.ByteAmount;
import com.twitter.heron.packing.ResourceExceededException;
import com.twitter.heron.spi.packing.Resource;
import com.twitter.heron.spi.utils.PackingTestUtils;

import static org.junit.Assert.assertArrayEquals;
import static org.junit.Assert.assertEquals;

/**
 * Tests scorers. Testing multiple scorers from a single test since the tests are so simple.
 */
public class ScorerTest {
  private Container[] testContainers;

  @Before
  public void init() throws ResourceExceededException {
    Resource containerCapacity
        = new Resource(1000, ByteAmount.fromGigabytes(100), ByteAmount.fromGigabytes(100));
    testContainers = new Container[] {
        new Container(1, containerCapacity, 0),
        new Container(3, containerCapacity, 0),
        new Container(4, containerCapacity, 0),
    };

    addInstance(testContainers[0], "A", 0);
    addInstance(testContainers[0], "A", 1);
    addInstance(testContainers[0], "B", 2);
    addInstance(testContainers[0], "B", 3);
    addInstance(testContainers[1], "A", 4);
    addInstance(testContainers[1], "B", 5);
    addInstance(testContainers[1], "B", 6);
    addInstance(testContainers[2], "A", 7);
    addInstance(testContainers[2], "A", 8);
  }

  @Test
  public void testHomogeneityScorer() {
    assertScores(
        new double[] {.5, 1.0 / 3, 1}, false, new HomogeneityScorer("A", false), testContainers);
    assertScores(
        new double[] {.5, 2.0 / 3, 0}, false, new HomogeneityScorer("B", false), testContainers);
  }

  @Test
  public void testHomogeneityScorerBinary() {
    assertScores(new double[] {0, 0, 1}, false, new HomogeneityScorer("A", true), testContainers);
  }

  @Test
  public void testContainerIdScorer() {
    assertScores(new double[] {1, 3, 4}, true, new ContainerIdScorer(), testContainers);
    assertScores(new double[] {1, 3, 4}, false, new ContainerIdScorer(false), testContainers);
  }

  @Test
  public void testContainerIdScorerFromId() {
    assertScores(new double[] {5, 0, 1}, true, new ContainerIdScorer(3, 4), testContainers);
  }

  @Test
  public void testInstanceCountScorer() {
    assertScores(new double[] {4, 3, 2}, true, new InstanceCountScorer(), testContainers);
  }

  private static void addInstance(Container container,
                                  String componentName,
                                  int taskId) throws ResourceExceededException {
    container.add(PackingTestUtils.testInstancePlan(componentName, taskId));
  }

  private static void assertScores(double[] expectedScores, boolean expectedAscending,
                                   Scorer<Container> scorer, Container... containers) {
    double[] results = new double[containers.length];
    int i = 0;
    for (Container container: containers) {
      results[i++] = scorer.getScore(container);
    }
    assertArrayEquals(expectedScores, results, 0.001);
    assertEquals(expectedAscending, scorer.sortAscending());
  }
}