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.runners.dataflow.worker;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.fail;
  
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.List;
  import java.util.NoSuchElementException;
  import org.apache.beam.runners.dataflow.worker.util.common.worker.ShuffleEntry;
  import org.apache.beam.sdk.util.common.Reiterator;
  import org.apache.beam.sdk.values.KV;
  import org.junit.Test;
  import org.junit.runner.RunWith;
  import org.junit.runners.JUnit4;
  
  /** Tests of TestShuffleReader. */
  @RunWith(JUnit4.class)
  public class TestShuffleReaderTest {
    static final String START_KEY = "ddd";
    static final String END_KEY = "mmm";
  
    static final List<KV<String, KV<String, String>>> NO_ENTRIES = Collections.emptyList();
  
    static final List<KV<String, KV<String, String>>> IN_RANGE_ENTRIES =
        Arrays.<KV<String, KV<String, String>>>asList(
            KV.of("ddd", KV.of("1", "in 1")),
            KV.of("ddd", KV.of("2", "in 1")),
            KV.of("ddd", KV.of("3", "in 1")),
            KV.of("dddd", KV.of("1", "in 2")),
            KV.of("dddd", KV.of("2", "in 2")),
            KV.of("de", KV.of("1", "in 3")),
            KV.of("ee", KV.of("1", "in 4")),
            KV.of("ee", KV.of("2", "in 4")),
            KV.of("ee", KV.of("3", "in 4")),
            KV.of("ee", KV.of("4", "in 4")),
            KV.of("mm", KV.of("1", "in 5")));
    static final List<KV<String, KV<String, String>>> BEFORE_RANGE_ENTRIES =
        Arrays.<KV<String, KV<String, String>>>asList(
            KV.of("", KV.of("1", "out 1")), KV.of("dd", KV.of("1", "out 2")));
    static final List<KV<String, KV<String, String>>> AFTER_RANGE_ENTRIES =
        Arrays.<KV<String, KV<String, String>>>asList(
            KV.of("mmm", KV.of("1", "out 3")),
            KV.of("mmm", KV.of("2", "out 3")),
            KV.of("mmmm", KV.of("1", "out 4")),
            KV.of("mn", KV.of("1", "out 5")),
            KV.of("zzz", KV.of("1", "out 6")));
    static final List<KV<String, KV<String, String>>> OUT_OF_RANGE_ENTRIES = new ArrayList<>();
  
    static {
      OUT_OF_RANGE_ENTRIES.addAll(BEFORE_RANGE_ENTRIES);
      OUT_OF_RANGE_ENTRIES.addAll(AFTER_RANGE_ENTRIES);
    }
  
    static final List<KV<String, KV<String, String>>> ALL_ENTRIES = new ArrayList<>();
  
    static {
      ALL_ENTRIES.addAll(BEFORE_RANGE_ENTRIES);
      ALL_ENTRIES.addAll(IN_RANGE_ENTRIES);
      ALL_ENTRIES.addAll(AFTER_RANGE_ENTRIES);
    }
  
    void runTest(
        List<KV<String, KV<String, String>>> expected,
        List<KV<String, KV<String, String>>> outOfRange,
        String startKey,
        String endKey) {
      TestShuffleReader shuffleReader = new TestShuffleReader();
      List<KV<String, KV<String, String>>> expectedCopy = new ArrayList<>(expected);
      expectedCopy.addAll(outOfRange);
      Collections.shuffle(expectedCopy);
      for (KV<String, KV<String, String>> entry : expectedCopy) {
        shuffleReader.addEntry(
            entry.getKey(),
            entry.getValue().getKey() /* secondary key */,
            entry.getValue().getValue());
      }
      testIteratorReturnsValues(shuffleReader.read(startKey, endKey), expected);
      testIteratorIntermediateCopiesReturnTails(shuffleReader.read(startKey, endKey), expected);
    }
  
    private void testIteratorReturnsValues(
        Reiterator<ShuffleEntry> iter, List<KV<String, KV<String, String>>> expected) {
      List<KV<String, KV<String, String>>> actual = readShuffleEntries(iter);
      try {
        iter.next();
        fail("should have failed");
      } catch (NoSuchElementException exn) {
        // Success.
      }
      assertEquals(expected, actual);
    }
  
    private List<KV<String, KV<String, String>>> readShuffleEntries(Reiterator<ShuffleEntry> iter) {
      List<KV<String, KV<String, String>>> actual = new ArrayList<>();
      while (iter.hasNext()) {
        ShuffleEntry entry = iter.next();
        actual.add(
            KV.of(
                (entry.getKey().toStringUtf8()),
                KV.of((entry.getSecondaryKey().toStringUtf8()), (entry.getValue().toStringUtf8()))));
      }
      return actual;
    }
  
    private void testIteratorIntermediateCopiesReturnTails(
        Reiterator<ShuffleEntry> iter, List<KV<String, KV<String, String>>> expected) {
      List<Reiterator<ShuffleEntry>> iteratorCopies = new ArrayList<>();
      for (; iter.hasNext(); iter.next()) {
        iteratorCopies.add(iter.copy());
      }
      for (int i = 0; i < expected.size(); ++i) {
        assertEquals(
            "" + i, expected.subList(i, expected.size()), readShuffleEntries(iteratorCopies.get(i)));
      }
    }
  
    @Test
    public void testEmpty() {
      runTest(NO_ENTRIES, NO_ENTRIES, null, null);
    }
  
    @Test
    public void testEmptyWithRange() {
      runTest(NO_ENTRIES, NO_ENTRIES, START_KEY, END_KEY);
    }
  
    @Test
    public void testNonEmpty() {
      runTest(ALL_ENTRIES, NO_ENTRIES, null, null);
    }
  
    @Test
    public void testNonEmptyWithAllInRange() {
      runTest(IN_RANGE_ENTRIES, NO_ENTRIES, START_KEY, END_KEY);
    }
  
    @Test
    public void testNonEmptyWithSomeOutOfRange() {
      runTest(IN_RANGE_ENTRIES, OUT_OF_RANGE_ENTRIES, START_KEY, END_KEY);
    }
  
    @Test
    public void testNonEmptyWithAllOutOfRange() {
      runTest(NO_ENTRIES, OUT_OF_RANGE_ENTRIES, START_KEY, END_KEY);
    }
  }
  