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.windmill.state;
  
  import static org.junit.Assert.assertEquals;
  
  import java.io.IOException;
  import java.util.Objects;
  import java.util.Optional;
  import org.apache.beam.runners.core.StateNamespace;
  import org.apache.beam.runners.core.StateNamespaces;
  import org.apache.beam.runners.core.StateTag;
  import org.apache.beam.runners.dataflow.options.DataflowWorkerHarnessOptions;
  import org.apache.beam.runners.dataflow.worker.WindmillComputationKey;
  import org.apache.beam.sdk.options.PipelineOptionsFactory;
  import org.apache.beam.sdk.state.State;
  import org.apache.beam.sdk.state.StateSpec;
  import org.apache.beam.sdk.transforms.windowing.IntervalWindow;
  import org.apache.beam.vendor.grpc.v1p69p0.com.google.protobuf.ByteString;
  import org.checkerframework.checker.nullness.qual.Nullable;
  import org.joda.time.Instant;
  import org.junit.Before;
  import org.junit.Rule;
  import org.junit.Test;
  import org.junit.rules.Timeout;
  import org.junit.runner.RunWith;
  import org.junit.runners.JUnit4;
  
  /** Tests for {@link org.apache.beam.runners.dataflow.worker.windmill.state.WindmillStateCache}. */
  @RunWith(JUnit4.class)
  public class WindmillStateCacheTest {
    @Rule public transient Timeout globalTimeout = Timeout.seconds(600);
    private static final String COMPUTATION = "computation";
    private static final long SHARDING_KEY = 123;
    private static final WindmillComputationKey COMPUTATION_KEY =
        WindmillComputationKey.create(COMPUTATION, ByteString.copyFromUtf8("key"), SHARDING_KEY);
    private static final String STATE_FAMILY = "family";
    private static final long MEGABYTES = 1024 * 1024;
    DataflowWorkerHarnessOptions options;
  
    private static class TestStateTag implements StateTag<TestState> {
  
      final String id;
  
      TestStateTag(String id) {
        this.id = id;
      }
  
      @Override
      public void appendTo(Appendable appendable) throws IOException {
        appendable.append(id);
      }
  
      @Override
      public String getId() {
        return id;
      }
  
      @Override
      public TestState bind(StateBinder binder) {
        throw new UnsupportedOperationException();
      }
  
      @Override
      public StateSpec<TestState> getSpec() {
        return null;
      }
  
      @Override
      public String toString() {
        return "Tag(" + id + ")";
      }
  
      @Override
      public boolean equals(@Nullable Object other) {
        return (other instanceof TestStateTag) && Objects.equals(((TestStateTag) other).id, id);
      }
  
      @Override
      public int hashCode() {
        return Objects.hash(id);
      }
    }
  
    private static class TestState implements State {
  
      String value = null;
  
      TestState(String value) {
        this.value = value;
      }
  
      @Override
      public void clear() {
        this.value = null;
      }
  
      @Override
      public boolean equals(@Nullable Object other) {
        return (other instanceof TestState) && Objects.equals(((TestState) other).value, value);
      }
  
      @Override
      public int hashCode() {
        return Objects.hash(value);
      }
  
      @Override
      public String toString() {
        return "State(" + value + ")";
      }
    }
  
    private static StateNamespace windowNamespace(long start) {
      return StateNamespaces.window(
          IntervalWindow.getCoder(), new IntervalWindow(new Instant(start), new Instant(start + 1)));
    }
  
    private static StateNamespace triggerNamespace(long start, int triggerIdx) {
      return StateNamespaces.windowAndTrigger(
          IntervalWindow.getCoder(),
          new IntervalWindow(new Instant(start), new Instant(start + 1)),
          triggerIdx);
    }
  
    private static WindmillComputationKey computationKey(
        String computationId, String key, long shardingKey) {
      return WindmillComputationKey.create(computationId, ByteString.copyFromUtf8(key), shardingKey);
    }
  
    WindmillStateCache cache;
  
    @Before
    public void setUp() {
      options = PipelineOptionsFactory.as(DataflowWorkerHarnessOptions.class);
      cache = WindmillStateCache.builder().setSizeMb(400).build();
      assertEquals(0, cache.getWeight());
    }
  
    @Test
    public void testBasic() throws Exception {
      WindmillStateCache.ForKeyAndFamily keyCache =
          cache.forComputation(COMPUTATION).forKey(COMPUTATION_KEY, 0L, 1L).forFamily(STATE_FAMILY);
      assertEquals(
          Optional.empty(), keyCache.get(StateNamespaces.global(), new TestStateTag("tag1")));
      assertEquals(Optional.empty(), keyCache.get(windowNamespace(0), new TestStateTag("tag2")));
      assertEquals(Optional.empty(), keyCache.get(triggerNamespace(0, 0), new TestStateTag("tag3")));
      assertEquals(Optional.empty(), keyCache.get(triggerNamespace(0, 0), new TestStateTag("tag2")));
      assertEquals(0, cache.getWeight());
  
      keyCache.put(StateNamespaces.global(), new TestStateTag("tag1"), new TestState("g1"), 2);
      keyCache.put(windowNamespace(0), new TestStateTag("tag2"), new TestState("w2"), 2);
  
      assertEquals(0, cache.getWeight());
      keyCache.persist();
      assertEquals(414, cache.getWeight());
  
      keyCache.put(triggerNamespace(0, 0), new TestStateTag("tag3"), new TestState("t3"), 2);
      keyCache.put(triggerNamespace(0, 0), new TestStateTag("tag2"), new TestState("t2"), 2);
  
      // Observes updated weight in entries, though cache will not know about it.
      assertEquals(482, cache.getWeight());
      keyCache.persist();
      assertEquals(482, cache.getWeight());
  
      keyCache =
          cache.forComputation(COMPUTATION).forKey(COMPUTATION_KEY, 0L, 2L).forFamily(STATE_FAMILY);
      assertEquals(
          Optional.of(new TestState("g1")),
          keyCache.get(StateNamespaces.global(), new TestStateTag("tag1")));
      assertEquals(
          Optional.of(new TestState("w2")),
          keyCache.get(windowNamespace(0), new TestStateTag("tag2")));
      assertEquals(
          Optional.of(new TestState("t3")),
          keyCache.get(triggerNamespace(0, 0), new TestStateTag("tag3")));
      assertEquals(
          Optional.of(new TestState("t2")),
          keyCache.get(triggerNamespace(0, 0), new TestStateTag("tag2")));
    }
  
    /** Verifies that max weight is set */
    @Test
    public void testMaxWeight() throws Exception {
      assertEquals(400 * MEGABYTES, cache.getMaxWeight());
    }
  
    /** Verifies that values are cached in the appropriate namespaces. */
    @Test
    public void testInvalidation() throws Exception {
      WindmillStateCache.ForKeyAndFamily keyCache =
          cache.forComputation(COMPUTATION).forKey(COMPUTATION_KEY, 0L, 1L).forFamily(STATE_FAMILY);
      assertEquals(
          Optional.empty(), keyCache.get(StateNamespaces.global(), new TestStateTag("tag1")));
      keyCache.put(StateNamespaces.global(), new TestStateTag("tag1"), new TestState("g1"), 2);
      keyCache.persist();
  
      keyCache =
          cache.forComputation(COMPUTATION).forKey(COMPUTATION_KEY, 0L, 2L).forFamily(STATE_FAMILY);
      assertEquals(207, cache.getWeight());
      assertEquals(
          Optional.of(new TestState("g1")),
          keyCache.get(StateNamespaces.global(), new TestStateTag("tag1")));
  
      keyCache =
          cache.forComputation(COMPUTATION).forKey(COMPUTATION_KEY, 1L, 3L).forFamily(STATE_FAMILY);
      assertEquals(
          Optional.empty(), keyCache.get(StateNamespaces.global(), new TestStateTag("tag1")));
      assertEquals(207, cache.getWeight());
    }
  
    /** Verifies that the cache is invalidated when the cache token changes. */
    @Test
    public void testEviction() throws Exception {
      WindmillStateCache.ForKeyAndFamily keyCache =
          cache.forComputation(COMPUTATION).forKey(COMPUTATION_KEY, 0L, 1L).forFamily(STATE_FAMILY);
      keyCache.put(windowNamespace(0), new TestStateTag("tag2"), new TestState("w2"), 2);
      keyCache.put(triggerNamespace(0, 0), new TestStateTag("tag3"), new TestState("t3"), 2000000000);
      keyCache.persist();
      assertEquals(0, cache.getWeight());
  
      // Eviction is atomic across the whole window.
      keyCache =
          cache.forComputation(COMPUTATION).forKey(COMPUTATION_KEY, 0L, 2L).forFamily(STATE_FAMILY);
      assertEquals(Optional.empty(), keyCache.get(windowNamespace(0), new TestStateTag("tag2")));
      assertEquals(Optional.empty(), keyCache.get(triggerNamespace(0, 0), new TestStateTag("tag3")));
    }
  
    /** Verifies that the cache does not vend for stale work tokens. */
    @Test
    public void testStaleWorkItem() throws Exception {
      TestStateTag tag = new TestStateTag("tag2");
  
      WindmillStateCache.ForKeyAndFamily keyCache =
          cache.forComputation(COMPUTATION).forKey(COMPUTATION_KEY, 0L, 2L).forFamily(STATE_FAMILY);
      keyCache.put(windowNamespace(0), tag, new TestState("w2"), 2);
  
      // Same cache.
      assertEquals(Optional.of(new TestState("w2")), keyCache.get(windowNamespace(0), tag));
      assertEquals(0, cache.getWeight());
      keyCache.persist();
      assertEquals(207, cache.getWeight());
      assertEquals(Optional.of(new TestState("w2")), keyCache.get(windowNamespace(0), tag));
  
      // Previous work token.
      keyCache =
          cache.forComputation(COMPUTATION).forKey(COMPUTATION_KEY, 0L, 1L).forFamily(STATE_FAMILY);
      assertEquals(Optional.empty(), keyCache.get(windowNamespace(0), tag));
  
      // Retry of work token that inserted.
      keyCache =
          cache.forComputation(COMPUTATION).forKey(COMPUTATION_KEY, 0L, 2L).forFamily(STATE_FAMILY);
      assertEquals(Optional.empty(), keyCache.get(windowNamespace(0), tag));
  
      keyCache =
          cache.forComputation(COMPUTATION).forKey(COMPUTATION_KEY, 0L, 10L).forFamily(STATE_FAMILY);
      assertEquals(Optional.empty(), keyCache.get(windowNamespace(0), tag));
      keyCache.put(windowNamespace(0), tag, new TestState("w3"), 2);
  
      // Ensure that second put updated work token.
      keyCache =
          cache.forComputation(COMPUTATION).forKey(COMPUTATION_KEY, 0L, 5L).forFamily(STATE_FAMILY);
      assertEquals(Optional.empty(), keyCache.get(windowNamespace(0), tag));
  
      keyCache =
          cache.forComputation(COMPUTATION).forKey(COMPUTATION_KEY, 0L, 15L).forFamily(STATE_FAMILY);
      assertEquals(Optional.empty(), keyCache.get(windowNamespace(0), tag));
    }
  
    /** Verifies that caches are kept independently per-key. */
    @Test
    public void testMultipleKeys() throws Exception {
      TestStateTag tag = new TestStateTag("tag1");
  
      WindmillStateCache.ForKeyAndFamily keyCache1 =
          cache
              .forComputation("comp1")
              .forKey(computationKey("comp1", "key1", SHARDING_KEY), 0L, 0L)
              .forFamily(STATE_FAMILY);
      WindmillStateCache.ForKeyAndFamily keyCache2 =
          cache
              .forComputation("comp1")
              .forKey(computationKey("comp1", "key2", SHARDING_KEY), 0L, 10L)
              .forFamily(STATE_FAMILY);
      WindmillStateCache.ForKeyAndFamily keyCache3 =
          cache
              .forComputation("comp2")
              .forKey(computationKey("comp2", "key1", SHARDING_KEY), 0L, 0L)
              .forFamily(STATE_FAMILY);
  
      TestState state1 = new TestState("g1");
      keyCache1.put(StateNamespaces.global(), tag, state1, 2);
      assertEquals(Optional.of(state1), keyCache1.get(StateNamespaces.global(), tag));
      keyCache1.persist();
  
      keyCache1 =
          cache
              .forComputation("comp1")
              .forKey(computationKey("comp1", "key1", SHARDING_KEY), 0L, 1L)
              .forFamily(STATE_FAMILY);
      assertEquals(Optional.of(state1), keyCache1.get(StateNamespaces.global(), tag));
      assertEquals(Optional.empty(), keyCache2.get(StateNamespaces.global(), tag));
      assertEquals(Optional.empty(), keyCache3.get(StateNamespaces.global(), tag));
  
      TestState state2 = new TestState("g2");
      keyCache2.put(StateNamespaces.global(), tag, state2, 2);
      keyCache2.persist();
      assertEquals(Optional.of(state2), keyCache2.get(StateNamespaces.global(), tag));
      keyCache2 =
          cache
              .forComputation("comp1")
              .forKey(computationKey("comp1", "key2", SHARDING_KEY), 0L, 20L)
              .forFamily(STATE_FAMILY);
      assertEquals(Optional.of(state2), keyCache2.get(StateNamespaces.global(), tag));
      assertEquals(Optional.of(state1), keyCache1.get(StateNamespaces.global(), tag));
      assertEquals(Optional.empty(), keyCache3.get(StateNamespaces.global(), tag));
    }
  
    /** Verifies that caches are kept independently per shard of key. */
    @Test
    public void testMultipleShardsOfKey() throws Exception {
      TestStateTag tag = new TestStateTag("tag1");
  
      WindmillStateCache.ForKeyAndFamily key1CacheShard1 =
          cache
              .forComputation(COMPUTATION)
              .forKey(computationKey(COMPUTATION, "key1", 1), 0L, 0L)
              .forFamily(STATE_FAMILY);
      WindmillStateCache.ForKeyAndFamily key1CacheShard2 =
          cache
              .forComputation(COMPUTATION)
              .forKey(computationKey(COMPUTATION, "key1", 2), 0L, 0L)
              .forFamily(STATE_FAMILY);
      WindmillStateCache.ForKeyAndFamily key2CacheShard1 =
          cache
              .forComputation(COMPUTATION)
              .forKey(computationKey(COMPUTATION, "key2", 1), 0L, 0L)
              .forFamily(STATE_FAMILY);
  
      TestState state1 = new TestState("g1");
      key1CacheShard1.put(StateNamespaces.global(), tag, state1, 2);
      key1CacheShard1.persist();
      assertEquals(Optional.of(state1), key1CacheShard1.get(StateNamespaces.global(), tag));
      key1CacheShard1 =
          cache
              .forComputation(COMPUTATION)
              .forKey(computationKey(COMPUTATION, "key1", 1), 0L, 1L)
              .forFamily(STATE_FAMILY);
      assertEquals(Optional.of(state1), key1CacheShard1.get(StateNamespaces.global(), tag));
      assertEquals(Optional.empty(), key1CacheShard2.get(StateNamespaces.global(), tag));
      assertEquals(Optional.empty(), key2CacheShard1.get(StateNamespaces.global(), tag));
  
      TestState state2 = new TestState("g2");
      key1CacheShard2.put(StateNamespaces.global(), tag, state2, 2);
      assertEquals(Optional.of(state2), key1CacheShard2.get(StateNamespaces.global(), tag));
      key1CacheShard2.persist();
      key1CacheShard2 =
          cache
              .forComputation(COMPUTATION)
              .forKey(computationKey(COMPUTATION, "key1", 2), 0L, 20L)
              .forFamily(STATE_FAMILY);
      assertEquals(Optional.of(state2), key1CacheShard2.get(StateNamespaces.global(), tag));
      assertEquals(Optional.of(state1), key1CacheShard1.get(StateNamespaces.global(), tag));
      assertEquals(Optional.empty(), key2CacheShard1.get(StateNamespaces.global(), tag));
    }
  
    /** Verifies that caches are kept independently per-family. */
    @Test
    public void testMultipleFamilies() throws Exception {
      TestStateTag tag = new TestStateTag("tag1");
  
      WindmillStateCache.ForKey keyCache =
          cache.forComputation("comp1").forKey(computationKey("comp1", "key1", SHARDING_KEY), 0L, 0L);
      WindmillStateCache.ForKeyAndFamily family1 = keyCache.forFamily("family1");
      WindmillStateCache.ForKeyAndFamily family2 = keyCache.forFamily("family2");
  
      TestState state1 = new TestState("g1");
      family1.put(StateNamespaces.global(), tag, state1, 2);
      assertEquals(Optional.of(state1), family1.get(StateNamespaces.global(), tag));
      family1.persist();
  
      TestState state2 = new TestState("g2");
      family2.put(StateNamespaces.global(), tag, state2, 2);
      family2.persist();
      assertEquals(Optional.of(state2), family2.get(StateNamespaces.global(), tag));
  
      keyCache =
          cache.forComputation("comp1").forKey(computationKey("comp1", "key1", SHARDING_KEY), 0L, 1L);
      family1 = keyCache.forFamily("family1");
      family2 = keyCache.forFamily("family2");
      WindmillStateCache.ForKeyAndFamily family3 = keyCache.forFamily("family3");
      assertEquals(Optional.of(state1), family1.get(StateNamespaces.global(), tag));
      assertEquals(Optional.of(state2), family2.get(StateNamespaces.global(), tag));
      assertEquals(Optional.empty(), family3.get(StateNamespaces.global(), tag));
    }
  
    /** Verifies explicit invalidation does indeed invalidate the correct entries. */
    @Test
    public void testExplicitInvalidation() throws Exception {
      WindmillStateCache.ForKeyAndFamily keyCache1 =
          cache
              .forComputation("comp1")
              .forKey(computationKey("comp1", "key1", 1), 0L, 0L)
              .forFamily(STATE_FAMILY);
      WindmillStateCache.ForKeyAndFamily keyCache2 =
          cache
              .forComputation("comp1")
              .forKey(computationKey("comp1", "key2", SHARDING_KEY), 0L, 0L)
              .forFamily(STATE_FAMILY);
      WindmillStateCache.ForKeyAndFamily keyCache3 =
          cache
              .forComputation("comp2")
              .forKey(computationKey("comp2", "key1", SHARDING_KEY), 0L, 0L)
              .forFamily(STATE_FAMILY);
      WindmillStateCache.ForKeyAndFamily keyCache4 =
          cache
              .forComputation("comp1")
              .forKey(computationKey("comp1", "key1", 2), 0L, 0L)
              .forFamily(STATE_FAMILY);
  
      keyCache1.put(StateNamespaces.global(), new TestStateTag("tag1"), new TestState("g1"), 1);
      keyCache1.persist();
      keyCache2.put(StateNamespaces.global(), new TestStateTag("tag2"), new TestState("g2"), 2);
      keyCache2.persist();
      keyCache3.put(StateNamespaces.global(), new TestStateTag("tag3"), new TestState("g3"), 3);
      keyCache3.persist();
      keyCache4.put(StateNamespaces.global(), new TestStateTag("tag4"), new TestState("g4"), 4);
      keyCache4.persist();
      keyCache1 =
          cache
              .forComputation("comp1")
              .forKey(computationKey("comp1", "key1", 1), 0L, 1L)
              .forFamily(STATE_FAMILY);
      keyCache2 =
          cache
              .forComputation("comp1")
              .forKey(computationKey("comp1", "key2", SHARDING_KEY), 0L, 1L)
              .forFamily(STATE_FAMILY);
      keyCache3 =
          cache
              .forComputation("comp2")
              .forKey(computationKey("comp2", "key1", SHARDING_KEY), 0L, 1L)
              .forFamily(STATE_FAMILY);
      keyCache4 =
          cache
              .forComputation("comp1")
              .forKey(computationKey("comp1", "key1", 2), 0L, 1L)
              .forFamily(STATE_FAMILY);
      assertEquals(
          Optional.of(new TestState("g1")),
          keyCache1.get(StateNamespaces.global(), new TestStateTag("tag1")));
      assertEquals(
          Optional.of(new TestState("g2")),
          keyCache2.get(StateNamespaces.global(), new TestStateTag("tag2")));
      assertEquals(
          Optional.of(new TestState("g3")),
          keyCache3.get(StateNamespaces.global(), new TestStateTag("tag3")));
      assertEquals(
          Optional.of(new TestState("g4")),
          keyCache4.get(StateNamespaces.global(), new TestStateTag("tag4")));
  
      // Invalidation of key 1 shard 1 does not affect another shard of key 1 or other keys.
      cache.forComputation("comp1").invalidate(ByteString.copyFromUtf8("key1"), 1);
      keyCache1 =
          cache
              .forComputation("comp1")
              .forKey(computationKey("comp1", "key1", 1), 0L, 2L)
              .forFamily(STATE_FAMILY);
  
      assertEquals(
          Optional.empty(), keyCache1.get(StateNamespaces.global(), new TestStateTag("tag1")));
      assertEquals(
          Optional.of(new TestState("g2")),
          keyCache2.get(StateNamespaces.global(), new TestStateTag("tag2")));
      assertEquals(
          Optional.of(new TestState("g3")),
          keyCache3.get(StateNamespaces.global(), new TestStateTag("tag3")));
      assertEquals(
          Optional.of(new TestState("g4")),
          keyCache4.get(StateNamespaces.global(), new TestStateTag("tag4")));
  
      // Invalidation of an non-existing key affects nothing.
      cache.forComputation("comp1").invalidate(ByteString.copyFromUtf8("key1"), 3);
  
      assertEquals(
          Optional.of(new TestState("g2")),
          keyCache2.get(StateNamespaces.global(), new TestStateTag("tag2")));
      assertEquals(
          Optional.of(new TestState("g3")),
          keyCache3.get(StateNamespaces.global(), new TestStateTag("tag3")));
      assertEquals(
          Optional.of(new TestState("g4")),
          keyCache4.get(StateNamespaces.global(), new TestStateTag("tag4")));
    }
  
    private static class TestStateTagWithBadEquality extends TestStateTag {
  
      public TestStateTagWithBadEquality(String id) {
        super(id);
      }
  
      @Override
      public boolean equals(@Nullable Object other) {
        return this == other;
      }
  
      @Override
      public int hashCode() {
        return System.identityHashCode(this);
      }
    }
  
    /**
     * Verifies that caching works properly even when the StateTag does not properly implement
     * equals() and hashCode()
     */
    @Test
    public void testBadCoderEquality() throws Exception {
      WindmillStateCache.ForKeyAndFamily keyCache1 =
          cache.forComputation(COMPUTATION).forKey(COMPUTATION_KEY, 0L, 0L).forFamily(STATE_FAMILY);
  
      StateTag<TestState> tag = new TestStateTagWithBadEquality("tag1");
      keyCache1.put(StateNamespaces.global(), tag, new TestState("g1"), 1);
      keyCache1.persist();
  
      keyCache1 =
          cache.forComputation(COMPUTATION).forKey(COMPUTATION_KEY, 0L, 1L).forFamily(STATE_FAMILY);
      assertEquals(Optional.of(new TestState("g1")), keyCache1.get(StateNamespaces.global(), tag));
      assertEquals(
          Optional.of(new TestState("g1")),
          keyCache1.get(StateNamespaces.global(), new TestStateTagWithBadEquality("tag1")));
    }
  }
  