QuorumMajorityTest.java

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 * Licensed to the Apache Software Foundation (ASF) under one
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 * 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,
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 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.zookeeper.test;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertTrue;
import java.util.ArrayList;
import org.apache.zookeeper.jmx.MBeanRegistry;
import org.apache.zookeeper.server.quorum.Leader.Proposal;
import org.apache.zookeeper.server.quorum.QuorumPeer;
import org.apache.zookeeper.server.quorum.QuorumPeer.ServerState;
import org.junit.jupiter.api.Test;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class QuorumMajorityTest extends QuorumBase {

    protected static final Logger LOG = LoggerFactory.getLogger(QuorumMajorityTest.class);
    public static final long CONNECTION_TIMEOUT = ClientTest.CONNECTION_TIMEOUT;

    /***************************************************************/
    /* Test that the majority quorum verifier only counts votes from */
    /* followers in its view                                    */
    /***************************************************************/
    @Test
    public void testMajQuorums() throws Throwable {
        LOG.info("Verify QuorumPeer#electionTimeTaken jmx bean attribute");

        ArrayList<QuorumPeer> peers = getPeerList();
        for (int i = 1; i <= peers.size(); i++) {
            QuorumPeer qp = peers.get(i - 1);
            Long electionTimeTaken = -1L;
            String bean = "";
            if (qp.getPeerState() == ServerState.FOLLOWING) {
                bean = String.format("%s:name0=ReplicatedServer_id%d,name1=replica.%d,name2=Follower", MBeanRegistry.DOMAIN, i, i);
            } else if (qp.getPeerState() == ServerState.LEADING) {
                bean = String.format("%s:name0=ReplicatedServer_id%d,name1=replica.%d,name2=Leader", MBeanRegistry.DOMAIN, i, i);
            }
            electionTimeTaken = (Long) JMXEnv.ensureBeanAttribute(bean, "ElectionTimeTaken");
            assertTrue(electionTimeTaken >= 0, "Wrong electionTimeTaken value!");
        }

        //setup servers 1-5 to be followers
        setUp(false, true);

        Proposal p = new Proposal();

        p.addQuorumVerifier(s1.getQuorumVerifier());

        // 2 followers out of 5 is not a majority
        p.addAck(Long.valueOf(1));
        p.addAck(Long.valueOf(2));
        assertEquals(false, p.hasAllQuorums());

        // 6 is not in the view - its vote shouldn't count
        p.addAck(Long.valueOf(6));
        assertEquals(false, p.hasAllQuorums());

        // 3 followers out of 5 are a majority of the voting view
        p.addAck(Long.valueOf(3));
        assertEquals(true, p.hasAllQuorums());

        //setup servers 1-3 to be followers and 4 and 5 to be observers
        setUp(true, true);

        p = new Proposal();
        p.addQuorumVerifier(s1.getQuorumVerifier());

        // 1 follower out of 3 is not a majority
        p.addAck(Long.valueOf(1));
        assertEquals(false, p.hasAllQuorums());

        // 4 and 5 are observers, their vote shouldn't count
        p.addAck(Long.valueOf(4));
        p.addAck(Long.valueOf(5));
        assertEquals(false, p.hasAllQuorums());

        // 6 is not in the view - its vote shouldn't count
        p.addAck(Long.valueOf(6));
        assertEquals(false, p.hasAllQuorums());

        // 2 followers out of 3 are a majority of the voting view
        p.addAck(Long.valueOf(2));
        assertEquals(true, p.hasAllQuorums());
    }

}