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.bifromq.basekv.raft.functest;
  
  import static org.apache.bifromq.basekv.raft.functest.RaftNodeGroup.DefaultRaftConfig;
  import static org.awaitility.Awaitility.await;
  import static org.testng.Assert.assertNotEquals;
  import static org.testng.Assert.assertTrue;
  
  import org.apache.bifromq.basekv.raft.RaftConfig;
  import org.apache.bifromq.basekv.raft.functest.template.RaftGroupTestTemplate;
  import com.google.protobuf.ByteString;
  import java.util.HashMap;
  import java.util.Map;
  import java.util.concurrent.TimeUnit;
  import lombok.extern.slf4j.Slf4j;
  import org.testng.annotations.Test;
  
  @Slf4j
  public class RaftConfigMigrationTest extends RaftGroupTestTemplate {
      @Test(groups = "integration")
      public void testLeaderElectionWithPreVoteMigration() {
          RaftConfig raftConfigWithPreVote = DefaultRaftConfig.toBuilder().preVote(true).build();
          RaftConfig raftConfigWithoutPreVote = DefaultRaftConfig.toBuilder().preVote(false).build();
          Map<String, RaftConfig> raftConfigs = new HashMap<String, RaftConfig>() {{
              put("V1", raftConfigWithPreVote);
              put("V2", raftConfigWithPreVote);
              put("V3", raftConfigWithoutPreVote);
          }};
          RaftNodeGroup group = new RaftNodeGroup(clusterConfig(), raftConfigs);
          // enough ticks for leader election
          group.run(10, TimeUnit.MILLISECONDS);
          await().until(() -> group.currentLeader().isPresent());
          String leader = group.currentLeader().get();
          assertTrue(group.awaitIndexCommitted(leader, 1));
          log.info("Leader {} elected", leader);
  
          String blockedFollower = group.currentFollowers().get(0);
          log.info("Follower {} isolating", blockedFollower);
          group.isolate(blockedFollower);
          group.propose(leader, ByteString.copyFromUtf8("appCommand1"));
          group.propose(leader, ByteString.copyFromUtf8("appCommand2"));
          assertTrue(group.awaitIndexCommitted(leader, 3));
          assertTrue(group.awaitIndexCommitted(group.currentFollowers().get(1), 3));
  
          // isolate leader, V3 and another follower will campaign, but V3 will not elected since that it has less logs
          group.recoverNetwork();
          log.info("Unblock {} and isolating Leader {}", blockedFollower, leader);
          group.isolate(leader);
          await().until(() -> group.currentLeader().isPresent() && !leader.equals(group.currentLeader().get()));
          String newLeader = group.currentLeader().get();
          log.info("New leader {} elected", newLeader);
          assertNotEquals(newLeader, leader);
          assertNotEquals(newLeader, blockedFollower);
      }
  }
  