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 com.datastax.oss.driver.internal.core.metadata.token;
  
  import static com.datastax.oss.driver.Assertions.assertThat;
  
  import com.datastax.oss.driver.api.core.metadata.Node;
  import com.datastax.oss.driver.api.core.metadata.token.Token;
  import com.datastax.oss.driver.shaded.guava.common.collect.ImmutableList;
  import com.datastax.oss.driver.shaded.guava.common.collect.ImmutableMap;
  import java.util.List;
  import java.util.Map;
  import java.util.Set;
  import org.junit.Test;
  import org.junit.runner.RunWith;
  import org.mockito.Mock;
  import org.mockito.junit.MockitoJUnitRunner;
  
  @RunWith(MockitoJUnitRunner.class)
  public class SimpleReplicationStrategyTest {
  
    private static final Token TOKEN01 = new Murmur3Token(-9000000000000000000L);
    private static final Token TOKEN02 = new Murmur3Token(-8000000000000000000L);
    private static final Token TOKEN03 = new Murmur3Token(-7000000000000000000L);
    private static final Token TOKEN04 = new Murmur3Token(-6000000000000000000L);
    private static final Token TOKEN05 = new Murmur3Token(-5000000000000000000L);
    private static final Token TOKEN06 = new Murmur3Token(-4000000000000000000L);
    private static final Token TOKEN07 = new Murmur3Token(-3000000000000000000L);
    private static final Token TOKEN08 = new Murmur3Token(-2000000000000000000L);
    private static final Token TOKEN09 = new Murmur3Token(-1000000000000000000L);
    private static final Token TOKEN10 = new Murmur3Token(0L);
    private static final Token TOKEN11 = new Murmur3Token(1000000000000000000L);
    private static final Token TOKEN12 = new Murmur3Token(2000000000000000000L);
    private static final Token TOKEN13 = new Murmur3Token(3000000000000000000L);
    private static final Token TOKEN14 = new Murmur3Token(4000000000000000000L);
    private static final Token TOKEN15 = new Murmur3Token(5000000000000000000L);
    private static final Token TOKEN16 = new Murmur3Token(6000000000000000000L);
    private static final Token TOKEN17 = new Murmur3Token(7000000000000000000L);
    private static final Token TOKEN18 = new Murmur3Token(8000000000000000000L);
    private static final Token TOKEN19 = new Murmur3Token(9000000000000000000L);
  
    @Mock private Node node1, node2, node3, node4, node5, node6;
  
    /** 4 tokens, 2 nodes, RF = 2. */
    @Test
    public void should_compute_for_simple_layout() {
      // Given
      List<Token> ring = ImmutableList.of(TOKEN01, TOKEN06, TOKEN14, TOKEN19);
      Map<Token, Node> tokenToPrimary =
          ImmutableMap.of(TOKEN01, node1, TOKEN06, node2, TOKEN14, node1, TOKEN19, node2);
      SimpleReplicationStrategy strategy = new SimpleReplicationStrategy(new ReplicationFactor(2));
  
      // When
      Map<Token, Set<Node>> replicasByToken = strategy.computeReplicasByToken(tokenToPrimary, ring);
  
      // Then
      assertThat(replicasByToken.keySet().size()).isEqualTo(ring.size());
      // Note: this also asserts the iteration order of the sets (unlike containsEntry(token, set))
      assertThat(replicasByToken.get(TOKEN01)).containsExactly(node1, node2);
      assertThat(replicasByToken.get(TOKEN06)).containsExactly(node2, node1);
      assertThat(replicasByToken.get(TOKEN14)).isSameAs(replicasByToken.get(TOKEN01));
      assertThat(replicasByToken.get(TOKEN19)).isSameAs(replicasByToken.get(TOKEN06));
    }
  
    /** 4 tokens, 2 nodes owning 2 consecutive tokens each, RF = 2. */
    @Test
    public void should_compute_when_nodes_own_consecutive_tokens() {
      // Given
      List<Token> ring = ImmutableList.of(TOKEN01, TOKEN06, TOKEN14, TOKEN19);
      Map<Token, Node> tokenToPrimary =
          ImmutableMap.of(TOKEN01, node1, TOKEN06, node1, TOKEN14, node2, TOKEN19, node2);
      SimpleReplicationStrategy strategy = new SimpleReplicationStrategy(new ReplicationFactor(2));
  
      // When
      Map<Token, Set<Node>> replicasByToken = strategy.computeReplicasByToken(tokenToPrimary, ring);
  
      // Then
      assertThat(replicasByToken.keySet().size()).isEqualTo(ring.size());
      assertThat(replicasByToken.get(TOKEN01)).containsExactly(node1, node2);
      assertThat(replicasByToken.get(TOKEN06)).isSameAs(replicasByToken.get(TOKEN01));
      assertThat(replicasByToken.get(TOKEN14)).containsExactly(node2, node1);
      assertThat(replicasByToken.get(TOKEN19)).isSameAs(replicasByToken.get(TOKEN14));
    }
  
    /** 4 tokens, 1 node owns 3 of them, RF = 2. */
    @Test
    public void should_compute_when_ring_unbalanced() {
      // Given
      List<Token> ring = ImmutableList.of(TOKEN01, TOKEN06, TOKEN14, TOKEN19);
      Map<Token, Node> tokenToPrimary =
          ImmutableMap.of(TOKEN01, node1, TOKEN06, node1, TOKEN14, node2, TOKEN19, node1);
      SimpleReplicationStrategy strategy = new SimpleReplicationStrategy(new ReplicationFactor(2));
  
      // When
      Map<Token, Set<Node>> replicasByToken = strategy.computeReplicasByToken(tokenToPrimary, ring);
  
      // Then
      assertThat(replicasByToken.keySet().size()).isEqualTo(ring.size());
      assertThat(replicasByToken.get(TOKEN01)).containsExactly(node1, node2);
      assertThat(replicasByToken.get(TOKEN06)).containsExactly(node1, node2);
      assertThat(replicasByToken.get(TOKEN14)).containsExactly(node2, node1);
      assertThat(replicasByToken.get(TOKEN19)).containsExactly(node1, node2);
    }
  
    /** 4 tokens, 2 nodes, RF = 6 (too large, should be <= number of nodes). */
    @Test
    public void should_compute_when_replication_factor_is_larger_than_cluster_size() {
      // Given
      List<Token> ring = ImmutableList.of(TOKEN01, TOKEN06, TOKEN14, TOKEN19);
      Map<Token, Node> tokenToPrimary =
          ImmutableMap.of(TOKEN01, node1, TOKEN06, node2, TOKEN14, node1, TOKEN19, node2);
      SimpleReplicationStrategy strategy = new SimpleReplicationStrategy(new ReplicationFactor(6));
  
      // When
      Map<Token, Set<Node>> replicasByToken = strategy.computeReplicasByToken(tokenToPrimary, ring);
  
      // Then
      assertThat(replicasByToken.keySet().size()).isEqualTo(ring.size());
      assertThat(replicasByToken.get(TOKEN01)).containsExactly(node1, node2);
      assertThat(replicasByToken.get(TOKEN06)).containsExactly(node2, node1);
      assertThat(replicasByToken.get(TOKEN14)).isSameAs(replicasByToken.get(TOKEN01));
      assertThat(replicasByToken.get(TOKEN19)).isSameAs(replicasByToken.get(TOKEN06));
    }
  
    @Test
    public void should_compute_for_complex_layout() {
      // Given
      List<Token> ring =
          ImmutableList.<Token>builder()
              .add(TOKEN01)
              .add(TOKEN02)
              .add(TOKEN03)
              .add(TOKEN04)
              .add(TOKEN05)
              .add(TOKEN06)
              .add(TOKEN07)
              .add(TOKEN08)
              .add(TOKEN09)
              .add(TOKEN10)
              .add(TOKEN11)
              .add(TOKEN12)
              .add(TOKEN13)
              .add(TOKEN14)
              .add(TOKEN15)
              .add(TOKEN16)
              .add(TOKEN17)
              .add(TOKEN18)
              .build();
      Map<Token, Node> tokenToPrimary =
          ImmutableMap.<Token, Node>builder()
              .put(TOKEN01, node1)
              .put(TOKEN02, node1)
              .put(TOKEN03, node5)
              .put(TOKEN04, node3)
              .put(TOKEN05, node1)
              .put(TOKEN06, node5)
              .put(TOKEN07, node2)
              .put(TOKEN08, node6)
              .put(TOKEN09, node3)
              .put(TOKEN10, node4)
              .put(TOKEN11, node5)
              .put(TOKEN12, node4)
              .put(TOKEN13, node4)
              .put(TOKEN14, node2)
              .put(TOKEN15, node6)
              .put(TOKEN16, node3)
              .put(TOKEN17, node2)
              .put(TOKEN18, node6)
              .build();
  
      SimpleReplicationStrategy strategy = new SimpleReplicationStrategy(new ReplicationFactor(3));
  
      // When
      Map<Token, Set<Node>> replicasByToken = strategy.computeReplicasByToken(tokenToPrimary, ring);
  
      // Then
      assertThat(replicasByToken.keySet().size()).isEqualTo(ring.size());
      assertThat(replicasByToken.get(TOKEN01)).containsExactly(node1, node5, node3);
      assertThat(replicasByToken.get(TOKEN02)).isSameAs(replicasByToken.get(TOKEN01));
      assertThat(replicasByToken.get(TOKEN03)).containsExactly(node5, node3, node1);
      assertThat(replicasByToken.get(TOKEN04)).containsExactly(node3, node1, node5);
      assertThat(replicasByToken.get(TOKEN05)).containsExactly(node1, node5, node2);
      assertThat(replicasByToken.get(TOKEN06)).containsExactly(node5, node2, node6);
      assertThat(replicasByToken.get(TOKEN07)).containsExactly(node2, node6, node3);
      assertThat(replicasByToken.get(TOKEN08)).containsExactly(node6, node3, node4);
      assertThat(replicasByToken.get(TOKEN09)).containsExactly(node3, node4, node5);
      assertThat(replicasByToken.get(TOKEN10)).containsExactly(node4, node5, node2);
      assertThat(replicasByToken.get(TOKEN11)).containsExactly(node5, node4, node2);
      assertThat(replicasByToken.get(TOKEN12)).containsExactly(node4, node2, node6);
      assertThat(replicasByToken.get(TOKEN13)).isSameAs(replicasByToken.get(TOKEN12));
      assertThat(replicasByToken.get(TOKEN14)).isSameAs(replicasByToken.get(TOKEN07));
      assertThat(replicasByToken.get(TOKEN15)).containsExactly(node6, node3, node2);
      assertThat(replicasByToken.get(TOKEN16)).containsExactly(node3, node2, node6);
      assertThat(replicasByToken.get(TOKEN17)).containsExactly(node2, node6, node1);
      assertThat(replicasByToken.get(TOKEN18)).containsExactly(node6, node1, node5);
    }
  }
  