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.core.triggers;
  
  import static org.junit.Assert.assertFalse;
  import static org.junit.Assert.assertTrue;
  
  import org.apache.beam.runners.core.triggers.TriggerStateMachineTester.SimpleTriggerStateMachineTester;
  import org.apache.beam.sdk.transforms.windowing.FixedWindows;
  import org.apache.beam.sdk.transforms.windowing.IntervalWindow;
  import org.apache.beam.sdk.transforms.windowing.Sessions;
  import org.apache.beam.sdk.transforms.windowing.SlidingWindows;
  import org.joda.time.Duration;
  import org.joda.time.Instant;
  import org.junit.Test;
  import org.junit.runner.RunWith;
  import org.junit.runners.JUnit4;
  
  /**
   * Tests the {@link DefaultTriggerStateMachine}, which should be equivalent to {@code
   * Repeatedly.forever(AfterWatermark.pastEndOfWindow())}.
   */
  @RunWith(JUnit4.class)
  public class DefaultTriggerStateMachineTest {
  
    SimpleTriggerStateMachineTester<IntervalWindow> tester;
  
    @Test
    public void testDefaultTriggerFixedWindows() throws Exception {
      tester =
          TriggerStateMachineTester.forTrigger(
              DefaultTriggerStateMachine.of(), FixedWindows.of(Duration.millis(100)));
  
      tester.injectElements(
          1, // [0, 100)
          101); // [100, 200)
  
      IntervalWindow firstWindow = new IntervalWindow(new Instant(0), new Instant(100));
      IntervalWindow secondWindow = new IntervalWindow(new Instant(100), new Instant(200));
  
      // Advance the watermark almost to the end of the first window.
      tester.advanceInputWatermark(new Instant(99));
      assertFalse(tester.shouldFire(firstWindow));
      assertFalse(tester.shouldFire(secondWindow));
  
      // Advance watermark past end of the first window, which is then ready
      tester.advanceInputWatermark(new Instant(100));
      assertTrue(tester.shouldFire(firstWindow));
      assertFalse(tester.shouldFire(secondWindow));
  
      // Fire, but the first window is still allowed to fire
      tester.fireIfShouldFire(firstWindow);
      assertTrue(tester.shouldFire(firstWindow));
      assertFalse(tester.shouldFire(secondWindow));
  
      // Advance watermark to 200, then both are ready
      tester.advanceInputWatermark(new Instant(200));
      assertTrue(tester.shouldFire(firstWindow));
      assertTrue(tester.shouldFire(secondWindow));
  
      assertFalse(tester.isMarkedFinished(firstWindow));
      assertFalse(tester.isMarkedFinished(secondWindow));
    }
  
    @Test
    public void testDefaultTriggerSlidingWindows() throws Exception {
      tester =
          TriggerStateMachineTester.forTrigger(
              DefaultTriggerStateMachine.of(),
              SlidingWindows.of(Duration.millis(100)).every(Duration.millis(50)));
  
      tester.injectElements(
          1, // [-50, 50), [0, 100)
          50); // [0, 100), [50, 150)
  
      IntervalWindow firstWindow = new IntervalWindow(new Instant(-50), new Instant(50));
      IntervalWindow secondWindow = new IntervalWindow(new Instant(0), new Instant(100));
      IntervalWindow thirdWindow = new IntervalWindow(new Instant(50), new Instant(150));
  
      assertFalse(tester.shouldFire(firstWindow));
      assertFalse(tester.shouldFire(secondWindow));
      assertFalse(tester.shouldFire(thirdWindow));
  
      // At 50, the first becomes ready; it stays ready after firing
      tester.advanceInputWatermark(new Instant(50));
      assertTrue(tester.shouldFire(firstWindow));
      assertFalse(tester.shouldFire(secondWindow));
      assertFalse(tester.shouldFire(thirdWindow));
      tester.fireIfShouldFire(firstWindow);
      assertTrue(tester.shouldFire(firstWindow));
      assertFalse(tester.shouldFire(secondWindow));
      assertFalse(tester.shouldFire(thirdWindow));
  
      // At 99, the first is still the only one ready
      tester.advanceInputWatermark(new Instant(99));
      assertTrue(tester.shouldFire(firstWindow));
      assertFalse(tester.shouldFire(secondWindow));
      assertFalse(tester.shouldFire(thirdWindow));
  
      // At 100, the first and second are ready
      tester.advanceInputWatermark(new Instant(100));
      assertTrue(tester.shouldFire(firstWindow));
      assertTrue(tester.shouldFire(secondWindow));
      assertFalse(tester.shouldFire(thirdWindow));
      tester.fireIfShouldFire(firstWindow);
  
      assertFalse(tester.isMarkedFinished(firstWindow));
      assertFalse(tester.isMarkedFinished(secondWindow));
      assertFalse(tester.isMarkedFinished(thirdWindow));
    }
  
    @Test
    public void testDefaultTriggerSessions() throws Exception {
      tester =
          TriggerStateMachineTester.forTrigger(
              DefaultTriggerStateMachine.of(), Sessions.withGapDuration(Duration.millis(100)));
  
      tester.injectElements(
          1, // [1, 101)
          50); // [50, 150)
      tester.mergeWindows();
  
      IntervalWindow firstWindow = new IntervalWindow(new Instant(1), new Instant(101));
      IntervalWindow secondWindow = new IntervalWindow(new Instant(50), new Instant(150));
      IntervalWindow mergedWindow = new IntervalWindow(new Instant(1), new Instant(150));
  
      // Not ready in any window yet
      tester.advanceInputWatermark(new Instant(100));
      assertFalse(tester.shouldFire(firstWindow));
      assertFalse(tester.shouldFire(secondWindow));
      assertFalse(tester.shouldFire(mergedWindow));
  
      // The first window is "ready": the caller owns knowledge of which windows are merged away
      tester.advanceInputWatermark(new Instant(149));
      assertTrue(tester.shouldFire(firstWindow));
      assertFalse(tester.shouldFire(secondWindow));
      assertFalse(tester.shouldFire(mergedWindow));
  
      // Now ready on all windows
      tester.advanceInputWatermark(new Instant(150));
      assertTrue(tester.shouldFire(firstWindow));
      assertTrue(tester.shouldFire(secondWindow));
      assertTrue(tester.shouldFire(mergedWindow));
  
      // Ensure it repeats
      tester.fireIfShouldFire(mergedWindow);
      assertTrue(tester.shouldFire(mergedWindow));
  
      assertFalse(tester.isMarkedFinished(mergedWindow));
    }
  }
  