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.kafka.streams.kstream.internals;
  
  import org.apache.kafka.common.serialization.Serdes;
  import org.apache.kafka.common.serialization.StringSerializer;
  import org.apache.kafka.common.utils.Bytes;
  import org.apache.kafka.streams.KeyValue;
  import org.apache.kafka.streams.KeyValueTimestamp;
  import org.apache.kafka.streams.StreamsBuilder;
  import org.apache.kafka.streams.StreamsConfig;
  import org.apache.kafka.streams.TestInputTopic;
  import org.apache.kafka.streams.TopologyTestDriver;
  import org.apache.kafka.streams.kstream.Consumed;
  import org.apache.kafka.streams.kstream.EmitStrategy;
  import org.apache.kafka.streams.kstream.Grouped;
  import org.apache.kafka.streams.kstream.KStream;
  import org.apache.kafka.streams.kstream.Materialized;
  import org.apache.kafka.streams.kstream.Merger;
  import org.apache.kafka.streams.kstream.Named;
  import org.apache.kafka.streams.kstream.SessionWindowedKStream;
  import org.apache.kafka.streams.kstream.SessionWindows;
  import org.apache.kafka.streams.kstream.Windowed;
  import org.apache.kafka.streams.state.SessionStore;
  import org.apache.kafka.streams.state.internals.ChangeLoggingSessionBytesStore;
  import org.apache.kafka.streams.state.internals.MeteredSessionStore;
  import org.apache.kafka.streams.state.internals.RocksDBTimeOrderedSessionStore;
  import org.apache.kafka.streams.state.internals.WrappedStateStore;
  import org.apache.kafka.test.MockAggregator;
  import org.apache.kafka.test.MockApiProcessorSupplier;
  import org.apache.kafka.test.MockInitializer;
  import org.apache.kafka.test.MockReducer;
  import org.apache.kafka.test.StreamsTestUtils;
  
  import org.junit.jupiter.params.ParameterizedTest;
  import org.junit.jupiter.params.provider.EnumSource;
  
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.List;
  import java.util.Properties;
  
  import static java.time.Duration.ofMillis;
  import static java.util.Arrays.asList;
  import static org.hamcrest.CoreMatchers.equalTo;
  import static org.hamcrest.MatcherAssert.assertThat;
  import static org.hamcrest.core.IsInstanceOf.instanceOf;
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  
  public class SessionWindowedKStreamImplTest {
      private static final String TOPIC = "input";
      private final StreamsBuilder builder = new StreamsBuilder();
      private final Properties props = StreamsTestUtils.getStreamsConfig(Serdes.String(), Serdes.String());
      private final Merger<String, String> sessionMerger = (aggKey, aggOne, aggTwo) -> aggOne + "+" + aggTwo;
  
      private SessionWindowedKStream<String, String> stream;
  
      public EmitStrategy.StrategyType type;
  
      private boolean emitFinal;
  
      public void setup(final EmitStrategy.StrategyType inputType) {
          type = inputType;
          final EmitStrategy emitStrategy = EmitStrategy.StrategyType.forType(type);
          emitFinal = type.equals(EmitStrategy.StrategyType.ON_WINDOW_CLOSE);
  
          final KStream<String, String> stream = builder.stream(TOPIC, Consumed.with(Serdes.String(), Serdes.String()));
          this.stream = stream.groupByKey(Grouped.with(Serdes.String(), Serdes.String()))
              .windowedBy(SessionWindows.ofInactivityGapWithNoGrace(ofMillis(500)))
              .emitStrategy(emitStrategy);
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldCountSessionWindowedWithCachingDisabled(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          props.put(StreamsConfig.STATESTORE_CACHE_MAX_BYTES_CONFIG, 0);
          shouldCountSessionWindowed();
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldCountSessionWindowedWithCachingEnabled(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          shouldCountSessionWindowed();
      }
  
      private void shouldCountSessionWindowed() {
          final MockApiProcessorSupplier<Windowed<String>, Long, Void, Void> supplier = new MockApiProcessorSupplier<>();
          stream.count()
              .toStream()
              .process(supplier);
  
          try (final TopologyTestDriver driver = new TopologyTestDriver(builder.build(), props)) {
              processData(driver);
          }
  
          final ArrayList<KeyValueTimestamp<Windowed<String>, Long>> processed =
              supplier.theCapturedProcessor().processed();
  
          if (emitFinal) {
              assertEquals(
                  Collections.singletonList(
                      new KeyValueTimestamp<>(new Windowed<>("1", new SessionWindow(10L, 15L)), 2L, 15L)
                  ),
                  processed
              );
          } else {
              assertEquals(
                  asList(
                      new KeyValueTimestamp<>(new Windowed<>("1", new SessionWindow(10L, 10L)), 1L, 10L),
                      new KeyValueTimestamp<>(new Windowed<>("1", new SessionWindow(10L, 10L)), null, 10L),
                      new KeyValueTimestamp<>(new Windowed<>("1", new SessionWindow(10L, 15L)), 2L, 15L),
                      new KeyValueTimestamp<>(new Windowed<>("1", new SessionWindow(600L, 600L)), 1L, 600L),
                      new KeyValueTimestamp<>(new Windowed<>("2", new SessionWindow(600L, 600L)), 1L, 600L),
                      new KeyValueTimestamp<>(new Windowed<>("2", new SessionWindow(600L, 600L)), null, 600L),
                      new KeyValueTimestamp<>(new Windowed<>("2", new SessionWindow(599L, 600L)), 2L, 600L)
                  ),
                  processed
              );
          }
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldReduceWindowed(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          final MockApiProcessorSupplier<Windowed<String>, String, Void, Void> supplier = new MockApiProcessorSupplier<>();
          stream.reduce(MockReducer.STRING_ADDER)
              .toStream()
              .process(supplier);
  
          try (final TopologyTestDriver driver = new TopologyTestDriver(builder.build(), props)) {
              processData(driver);
          }
  
          final ArrayList<KeyValueTimestamp<Windowed<String>, String>> processed =
                  supplier.theCapturedProcessor().processed();
  
          if (emitFinal) {
              assertEquals(
                  Collections.singletonList(
                      new KeyValueTimestamp<>(new Windowed<>("1", new SessionWindow(10L, 15L)), "1+2", 15L)
                  ),
                  processed
              );
          } else {
              assertEquals(
                  asList(
                      new KeyValueTimestamp<>(new Windowed<>("1", new SessionWindow(10L, 10L)), "1", 10L),
                      new KeyValueTimestamp<>(new Windowed<>("1", new SessionWindow(10L, 10L)), null, 10L),
                      new KeyValueTimestamp<>(new Windowed<>("1", new SessionWindow(10L, 15L)), "1+2", 15L),
                      new KeyValueTimestamp<>(new Windowed<>("1", new SessionWindow(600L, 600L)), "3", 600L),
                      new KeyValueTimestamp<>(new Windowed<>("2", new SessionWindow(600L, 600L)), "1", 600L),
                      new KeyValueTimestamp<>(new Windowed<>("2", new SessionWindow(600L, 600L)), null, 600L),
                      new KeyValueTimestamp<>(new Windowed<>("2", new SessionWindow(599L, 600L)), "1+2", 600L)
                  ),
                  processed
              );
          }
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldAggregateSessionWindowed(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          final MockApiProcessorSupplier<Windowed<String>, String, Void, Void> supplier = new MockApiProcessorSupplier<>();
          stream.aggregate(MockInitializer.STRING_INIT,
                           MockAggregator.TOSTRING_ADDER,
                           sessionMerger,
                           Materialized.with(Serdes.String(), Serdes.String()))
              .toStream()
              .process(supplier);
          try (final TopologyTestDriver driver = new TopologyTestDriver(builder.build(), props)) {
              processData(driver);
          }
  
          final ArrayList<KeyValueTimestamp<Windowed<String>, String>> processed =
                  supplier.theCapturedProcessor().processed();
  
          if (emitFinal) {
              assertEquals(
                  Collections.singletonList(
                      new KeyValueTimestamp<>(new Windowed<>("1", new SessionWindow(10L, 15L)), "0+0+1+2", 15L)
                  ),
                  processed
              );
          } else {
              assertEquals(
                  asList(
                      new KeyValueTimestamp<>(new Windowed<>("1", new SessionWindow(10L, 10L)), "0+1", 10L),
                      new KeyValueTimestamp<>(new Windowed<>("1", new SessionWindow(10L, 10L)), null, 10L),
                      new KeyValueTimestamp<>(new Windowed<>("1", new SessionWindow(10L, 15L)), "0+0+1+2", 15L),
                      new KeyValueTimestamp<>(new Windowed<>("1", new SessionWindow(600L, 600L)), "0+3", 600L),
                      new KeyValueTimestamp<>(new Windowed<>("2", new SessionWindow(600L, 600L)), "0+1", 600L),
                      new KeyValueTimestamp<>(new Windowed<>("2", new SessionWindow(600L, 600L)), null, 600L),
                      new KeyValueTimestamp<>(new Windowed<>("2", new SessionWindow(599L, 600L)), "0+0+1+2", 600L)
                  ),
                  processed
              );
          }
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldMaterializeCount(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          stream.count(Materialized.as("count-store"));
  
          try (final TopologyTestDriver driver = new TopologyTestDriver(builder.build(), props)) {
              processData(driver);
              final SessionStore<String, Long> store = driver.getSessionStore("count-store");
              final List<KeyValue<Windowed<String>, Long>> data = StreamsTestUtils.toListAndCloseIterator(store.fetch("1", "2"));
              if (!emitFinal) {
                  assertThat(
                          data,
                          equalTo(Arrays.asList(
                                  KeyValue.pair(new Windowed<>("1", new SessionWindow(10, 15)), 2L),
                                  KeyValue.pair(new Windowed<>("1", new SessionWindow(600, 600)), 1L),
                                  KeyValue.pair(new Windowed<>("2", new SessionWindow(599, 600)), 2L))));
              } else {
                  assertThat(
                          data,
                          equalTo(Arrays.asList(
                                  KeyValue.pair(new Windowed<>("1", new SessionWindow(600, 600)), 1L),
                                  KeyValue.pair(new Windowed<>("2", new SessionWindow(599, 600)), 2L))));
  
              }
          }
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldMaterializeReduced(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          stream.reduce(MockReducer.STRING_ADDER, Materialized.as("reduced"));
  
          try (final TopologyTestDriver driver = new TopologyTestDriver(builder.build(), props)) {
              processData(driver);
              final SessionStore<String, String> sessionStore = driver.getSessionStore("reduced");
              final List<KeyValue<Windowed<String>, String>> data = StreamsTestUtils.toListAndCloseIterator(sessionStore.fetch("1", "2"));
  
              if (!emitFinal) {
                  assertThat(
                          data,
                          equalTo(Arrays.asList(
                                  KeyValue.pair(new Windowed<>("1", new SessionWindow(10, 15)), "1+2"),
                                  KeyValue.pair(new Windowed<>("1", new SessionWindow(600, 600)), "3"),
                                  KeyValue.pair(new Windowed<>("2", new SessionWindow(599, 600)), "1+2"))));
              } else {
                  assertThat(
                          data,
                          equalTo(Arrays.asList(
                                  KeyValue.pair(new Windowed<>("1", new SessionWindow(600, 600)), "3"),
                                  KeyValue.pair(new Windowed<>("2", new SessionWindow(599, 600)), "1+2"))));
  
              }
          }
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldMaterializeAggregated(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          stream.aggregate(
              MockInitializer.STRING_INIT,
              MockAggregator.TOSTRING_ADDER,
              sessionMerger,
              Materialized.<String, String, SessionStore<Bytes, byte[]>>as("aggregated").withValueSerde(Serdes.String()));
  
          try (final TopologyTestDriver driver = new TopologyTestDriver(builder.build(), props)) {
              processData(driver);
              final SessionStore<String, String> sessionStore = driver.getSessionStore("aggregated");
              final List<KeyValue<Windowed<String>, String>> data = StreamsTestUtils.toListAndCloseIterator(sessionStore.fetch("1", "2"));
              if (!emitFinal) {
                  assertThat(
                          data,
                          equalTo(Arrays.asList(
                                  KeyValue.pair(new Windowed<>("1", new SessionWindow(10, 15)), "0+0+1+2"),
                                  KeyValue.pair(new Windowed<>("1", new SessionWindow(600, 600)), "0+3"),
                                  KeyValue.pair(new Windowed<>("2", new SessionWindow(599, 600)), "0+0+1+2"))));
              } else {
                  assertThat(
                          data,
                          equalTo(Arrays.asList(
                                  KeyValue.pair(new Windowed<>("1", new SessionWindow(600, 600)), "0+3"),
                                  KeyValue.pair(new Windowed<>("2", new SessionWindow(599, 600)), "0+0+1+2"))));
  
              }
          }
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldThrowNullPointerOnAggregateIfInitializerIsNull(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          assertThrows(NullPointerException.class, () -> stream.aggregate(null, MockAggregator.TOSTRING_ADDER, sessionMerger));
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldThrowNullPointerOnAggregateIfAggregatorIsNull(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          assertThrows(NullPointerException.class, () -> stream.aggregate(MockInitializer.STRING_INIT, null, sessionMerger));
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldThrowNullPointerOnAggregateIfMergerIsNull(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          assertThrows(NullPointerException.class, () -> stream.aggregate(MockInitializer.STRING_INIT, MockAggregator.TOSTRING_ADDER, null));
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldThrowNullPointerOnReduceIfReducerIsNull(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          assertThrows(NullPointerException.class, () -> stream.reduce(null));
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldThrowNullPointerOnMaterializedAggregateIfInitializerIsNull(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          assertThrows(NullPointerException.class, () -> stream.aggregate(
              null,
              MockAggregator.TOSTRING_ADDER,
              sessionMerger,
              Materialized.as("store")));
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldThrowNullPointerOnMaterializedAggregateIfAggregatorIsNull(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          assertThrows(NullPointerException.class, () -> stream.aggregate(
              MockInitializer.STRING_INIT,
              null,
              sessionMerger,
              Materialized.as("store")));
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldThrowNullPointerOnMaterializedAggregateIfMergerIsNull(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          assertThrows(NullPointerException.class, () -> stream.aggregate(
              MockInitializer.STRING_INIT,
              MockAggregator.TOSTRING_ADDER,
              null,
              Materialized.as("store")));
      }
  
      @SuppressWarnings("unchecked")
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldThrowNullPointerOnMaterializedAggregateIfMaterializedIsNull(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          assertThrows(NullPointerException.class, () -> stream.aggregate(
              MockInitializer.STRING_INIT,
              MockAggregator.TOSTRING_ADDER,
              sessionMerger,
              (Materialized) null));
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldThrowNullPointerOnMaterializedReduceIfReducerIsNull(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          assertThrows(NullPointerException.class, () -> stream.reduce(null, Materialized.as("store")));
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      @SuppressWarnings("unchecked")
      public void shouldThrowNullPointerOnMaterializedReduceIfMaterializedIsNull(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          assertThrows(NullPointerException.class, () -> stream.reduce(MockReducer.STRING_ADDER, (Materialized) null));
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldThrowNullPointerOnMaterializedReduceIfNamedIsNull(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          assertThrows(NullPointerException.class, () -> stream.reduce(MockReducer.STRING_ADDER, (Named) null));
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldThrowNullPointerOnCountIfMaterializedIsNull(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          assertThrows(NullPointerException.class, () -> stream.count((Materialized<String, Long, SessionStore<Bytes, byte[]>>) null));
      }
  
      @ParameterizedTest
      @EnumSource(EmitStrategy.StrategyType.class)
      public void shouldNotEnableCachingWithEmitFinal(final EmitStrategy.StrategyType inputType) {
          setup(inputType);
          if (!emitFinal)
              return;
  
          stream.aggregate(
                  MockInitializer.STRING_INIT,
                  MockAggregator.TOSTRING_ADDER,
                  sessionMerger,
                  Materialized.<String, String, SessionStore<Bytes, byte[]>>as("aggregated").withValueSerde(Serdes.String()));
  
          try (final TopologyTestDriver driver = new TopologyTestDriver(builder.build(), props)) {
              final SessionStore<String, String> store = driver.getSessionStore("aggregated");
              final WrappedStateStore changeLogging = (WrappedStateStore) ((WrappedStateStore) store).wrapped();
              assertThat(store, instanceOf(MeteredSessionStore.class));
              assertThat(changeLogging, instanceOf(ChangeLoggingSessionBytesStore.class));
              assertThat(changeLogging.wrapped(), instanceOf(RocksDBTimeOrderedSessionStore.class));
          }
      }
  
      private void processData(final TopologyTestDriver driver) {
          final TestInputTopic<String, String> inputTopic =
                  driver.createInputTopic(TOPIC, new StringSerializer(), new StringSerializer());
          inputTopic.pipeInput("1", "1", 10);
          inputTopic.pipeInput("1", "2", 15);
          inputTopic.pipeInput("1", "3", 600);
          inputTopic.pipeInput("2", "1", 600);
          inputTopic.pipeInput("2", "2", 599);
      }
  }
  