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.direct;
  
  import static org.hamcrest.MatcherAssert.assertThat;
  import static org.hamcrest.Matchers.equalTo;
  
  import java.util.concurrent.CountDownLatch;
  import java.util.concurrent.Executors;
  import java.util.concurrent.TimeUnit;
  import org.apache.beam.sdk.runners.AppliedPTransform;
  import org.apache.beam.sdk.testing.TestPipeline;
  import org.apache.beam.sdk.transforms.Create;
  import org.apache.beam.sdk.transforms.Sum;
  import org.apache.beam.sdk.transforms.windowing.BoundedWindow;
  import org.apache.beam.sdk.transforms.windowing.FixedWindows;
  import org.apache.beam.sdk.transforms.windowing.GlobalWindow;
  import org.apache.beam.sdk.transforms.windowing.IntervalWindow;
  import org.apache.beam.sdk.transforms.windowing.WindowFn;
  import org.apache.beam.sdk.values.PCollection;
  import org.apache.beam.sdk.values.WindowingStrategy;
  import org.joda.time.Duration;
  import org.joda.time.Instant;
  import org.junit.Before;
  import org.junit.Rule;
  import org.junit.Test;
  import org.junit.runner.RunWith;
  import org.junit.runners.JUnit4;
  
  /** Tests for {@link WatermarkCallbackExecutor}. */
  @RunWith(JUnit4.class)
  public class WatermarkCallbackExecutorTest {
    private WatermarkCallbackExecutor executor =
        WatermarkCallbackExecutor.create(Executors.newSingleThreadExecutor());
    private AppliedPTransform<?, ?, ?> create;
    private AppliedPTransform<?, ?, ?> sum;
  
    @Rule public TestPipeline p = TestPipeline.create().enableAbandonedNodeEnforcement(false);
  
    @Before
    public void setup() {
      PCollection<Integer> created = p.apply(Create.of(1, 2, 3));
      PCollection<Integer> summed = created.apply(Sum.integersGlobally());
      DirectGraphs.performDirectOverrides(p);
      DirectGraph graph = DirectGraphs.getGraph(p);
      create = graph.getProducer(created);
      sum = graph.getProducer(summed);
    }
  
    @Test
    public void onGuaranteedFiringFiresAfterTrigger() throws Exception {
      CountDownLatch latch = new CountDownLatch(1);
      executor.callOnGuaranteedFiring(
          create,
          GlobalWindow.INSTANCE,
          WindowingStrategy.globalDefault(),
          new CountDownLatchCallback(latch));
  
      executor.fireForWatermark(create, BoundedWindow.TIMESTAMP_MAX_VALUE);
      assertThat(latch.await(500, TimeUnit.MILLISECONDS), equalTo(true));
    }
  
    @Test
    public void multipleCallbacksShouldFireFires() throws Exception {
      CountDownLatch latch = new CountDownLatch(2);
      WindowFn<Object, IntervalWindow> windowFn = FixedWindows.of(Duration.standardMinutes(10));
      IntervalWindow window =
          new IntervalWindow(new Instant(0L), new Instant(0L).plus(Duration.standardMinutes(10)));
      executor.callOnGuaranteedFiring(
          create, window, WindowingStrategy.of(windowFn), new CountDownLatchCallback(latch));
      executor.callOnGuaranteedFiring(
          create, window, WindowingStrategy.of(windowFn), new CountDownLatchCallback(latch));
  
      executor.fireForWatermark(create, new Instant(0L).plus(Duration.standardMinutes(10)));
      assertThat(latch.await(500, TimeUnit.MILLISECONDS), equalTo(true));
    }
  
    @Test
    public void noCallbacksShouldFire() throws Exception {
      CountDownLatch latch = new CountDownLatch(1);
      WindowFn<Object, IntervalWindow> windowFn = FixedWindows.of(Duration.standardMinutes(10));
      IntervalWindow window =
          new IntervalWindow(new Instant(0L), new Instant(0L).plus(Duration.standardMinutes(10)));
      executor.callOnGuaranteedFiring(
          create, window, WindowingStrategy.of(windowFn), new CountDownLatchCallback(latch));
  
      executor.fireForWatermark(create, new Instant(0L).plus(Duration.standardMinutes(5)));
      assertThat(latch.await(500, TimeUnit.MILLISECONDS), equalTo(false));
    }
  
    @Test
    public void unrelatedStepShouldNotFire() throws Exception {
      CountDownLatch latch = new CountDownLatch(1);
      WindowFn<Object, IntervalWindow> windowFn = FixedWindows.of(Duration.standardMinutes(10));
      IntervalWindow window =
          new IntervalWindow(new Instant(0L), new Instant(0L).plus(Duration.standardMinutes(10)));
      executor.callOnGuaranteedFiring(
          sum, window, WindowingStrategy.of(windowFn), new CountDownLatchCallback(latch));
  
      executor.fireForWatermark(create, new Instant(0L).plus(Duration.standardMinutes(20)));
      assertThat(latch.await(500, TimeUnit.MILLISECONDS), equalTo(false));
    }
  
    private static class CountDownLatchCallback implements Runnable {
      private final CountDownLatch latch;
  
      public CountDownLatchCallback(CountDownLatch latch) {
        this.latch = latch;
      }
  
      @Override
      public void run() {
        latch.countDown();
      }
    }
  }
  