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.sdk.testing;
  
  import static org.junit.Assert.fail;
  
  import java.io.Serializable;
  import org.apache.beam.sdk.io.GenerateSequence;
  import org.apache.beam.sdk.transforms.Flatten;
  import org.apache.beam.sdk.transforms.GroupByKey;
  import org.apache.beam.sdk.transforms.Values;
  import org.apache.beam.sdk.transforms.WithKeys;
  import org.apache.beam.sdk.transforms.WithTimestamps;
  import org.apache.beam.sdk.transforms.windowing.AfterPane;
  import org.apache.beam.sdk.transforms.windowing.AfterWatermark;
  import org.apache.beam.sdk.transforms.windowing.FixedWindows;
  import org.apache.beam.sdk.transforms.windowing.Window;
  import org.apache.beam.sdk.values.PCollection;
  import org.apache.beam.sdk.values.PCollectionList;
  import org.apache.beam.sdk.values.TypeDescriptor;
  import org.apache.beam.sdk.values.ValueInSingleWindow;
  import org.apache.beam.vendor.guava.v32_1_2_jre.com.google.common.collect.Iterables;
  import org.joda.time.Duration;
  import org.joda.time.Instant;
  import org.junit.Rule;
  import org.junit.Test;
  import org.junit.experimental.categories.Category;
  import org.junit.runner.RunWith;
  import org.junit.runners.JUnit4;
  
  /** Tests for {@link GatherAllPanes}. */
  @RunWith(JUnit4.class)
  public class GatherAllPanesTest implements Serializable {
  
    @Rule public transient TestPipeline p = TestPipeline.create();
  
    @Test
    @Category(NeedsRunner.class)
    public void singlePaneSingleReifiedPane() {
      PCollection<Iterable<ValueInSingleWindow<Iterable<Long>>>> accumulatedPanes =
          p.apply(GenerateSequence.from(0).to(20000))
              .apply(WithTimestamps.of(input -> new Instant(input * 10)))
              .apply(
                  Window.<Long>into(FixedWindows.of(Duration.standardMinutes(1)))
                      .triggering(AfterWatermark.pastEndOfWindow())
                      .withAllowedLateness(Duration.ZERO)
                      .discardingFiredPanes())
              .apply(WithKeys.<Void, Long>of((Void) null).withKeyType(new TypeDescriptor<Void>() {}))
              .apply(GroupByKey.create())
              .apply(Values.create())
              .apply(GatherAllPanes.globally());
  
      PAssert.that(accumulatedPanes)
          .satisfies(
              input -> {
                for (Iterable<ValueInSingleWindow<Iterable<Long>>> windowedInput : input) {
                  if (Iterables.size(windowedInput) > 1) {
                    fail("Expected all windows to have exactly one pane, got " + windowedInput);
                    return null;
                  }
                }
                return null;
              });
  
      p.run();
    }
  
    @Test
    @Category(NeedsRunner.class)
    public void multiplePanesMultipleReifiedPane() {
      PCollection<Long> someElems = p.apply("someLongs", GenerateSequence.from(0).to(20000));
      PCollection<Long> otherElems = p.apply("otherLongs", GenerateSequence.from(0).to(20000));
      PCollection<Iterable<ValueInSingleWindow<Iterable<Long>>>> accumulatedPanes =
          PCollectionList.of(someElems)
              .and(otherElems)
              .apply(Flatten.pCollections())
              .apply(WithTimestamps.of(input -> new Instant(input * 10)))
              .apply(
                  Window.<Long>into(FixedWindows.of(Duration.standardMinutes(1)))
                      .triggering(
                          AfterWatermark.pastEndOfWindow()
                              .withEarlyFirings(AfterPane.elementCountAtLeast(1)))
                      .withAllowedLateness(Duration.ZERO)
                      .discardingFiredPanes())
              .apply(WithKeys.<Void, Long>of((Void) null).withKeyType(new TypeDescriptor<Void>() {}))
              .apply(GroupByKey.create())
              .apply(Values.create())
              .apply(GatherAllPanes.globally());
  
      PAssert.that(accumulatedPanes)
          .satisfies(
              input -> {
                for (Iterable<ValueInSingleWindow<Iterable<Long>>> windowedInput : input) {
                  if (Iterables.size(windowedInput) > 1) {
                    return null;
                  }
                }
                fail("Expected at least one window to have multiple panes");
                return null;
              });
  
      p.run();
    }
  }
  