com.linkedin.pinot.tools.PinotZKChanger.java Source code

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Here is the source code for com.linkedin.pinot.tools.PinotZKChanger.java

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/**
 * Copyright (C) 2014-2016 LinkedIn Corp. (pinot-core@linkedin.com)
 *
 * Licensed 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.linkedin.pinot.tools;

import java.io.StringWriter;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.TreeMap;
import org.apache.commons.math.stat.descriptive.DescriptiveStatistics;
import org.apache.helix.HelixManager;
import org.apache.helix.HelixManagerFactory;
import org.apache.helix.InstanceType;
import org.apache.helix.PropertyPathConfig;
import org.apache.helix.PropertyType;
import org.apache.helix.ZNRecord;
import org.apache.helix.manager.zk.ZKHelixAdmin;
import org.apache.helix.manager.zk.ZNRecordSerializer;
import org.apache.helix.model.ExternalView;
import org.apache.helix.model.IdealState;
import org.apache.helix.store.zk.ZkHelixPropertyStore;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.fasterxml.jackson.databind.ObjectMapper;

/**
 * This class provides utilities that change zookeeper state in a cluster
 */
public class PinotZKChanger {
    private static final Logger LOGGER = LoggerFactory.getLogger(PinotZKChanger.class);

    protected ZKHelixAdmin helixAdmin;
    protected HelixManager helixManager;
    protected String clusterName;
    protected ZkHelixPropertyStore<ZNRecord> propertyStore;
    protected ObjectMapper objectMapper;

    public PinotZKChanger(String zkAddress, String clusterName) {
        this.clusterName = clusterName;
        helixAdmin = new ZKHelixAdmin(zkAddress);
        helixManager = HelixManagerFactory.getZKHelixManager(clusterName, "PinotNumReplicaChanger",
                InstanceType.ADMINISTRATOR, zkAddress);
        try {
            helixManager.connect();
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
        ZNRecordSerializer serializer = new ZNRecordSerializer();
        String path = PropertyPathConfig.getPath(PropertyType.PROPERTYSTORE, clusterName);
        propertyStore = new ZkHelixPropertyStore<>(zkAddress, serializer, path);
        objectMapper = new ObjectMapper();
    }

    public ZKHelixAdmin getHelixAdmin() {
        return helixAdmin;
    }

    /**
     * return true if IdealState = ExternalView
     * @return
     */
    public int isStable(String tableName) {
        IdealState idealState = helixAdmin.getResourceIdealState(clusterName, tableName);
        ExternalView externalView = helixAdmin.getResourceExternalView(clusterName, tableName);
        Map<String, Map<String, String>> mapFieldsIS = idealState.getRecord().getMapFields();
        Map<String, Map<String, String>> mapFieldsEV = externalView.getRecord().getMapFields();
        int numDiff = 0;
        for (String segment : mapFieldsIS.keySet()) {
            Map<String, String> mapIS = mapFieldsIS.get(segment);
            Map<String, String> mapEV = mapFieldsEV.get(segment);

            for (String server : mapIS.keySet()) {
                String state = mapIS.get(server);
                if (mapEV == null || mapEV.get(server) == null || !mapEV.get(server).equals(state)) {
                    LOGGER.info("Mismatch: segment" + segment + " server:" + server + " state:" + state);
                    numDiff = numDiff + 1;
                }
            }
        }
        return numDiff;
    }

    /**
     * Wait till state has stabilized {@link #isStable(String)}
     * @param resourceName
     * @throws InterruptedException
     */
    public void waitForStable(String resourceName) throws InterruptedException {
        int diff;
        Thread.sleep(3000);
        do {
            diff = isStable(resourceName);
            if (diff == 0) {
                break;
            } else {
                LOGGER.info("Waiting for externalView to match idealstate for table:" + resourceName
                        + " Num segments difference:" + diff);
                Thread.sleep(30000);
            }
        } while (diff > 0);
    }

    protected void printSegmentAssignment(Map<String, Map<String, String>> mapping) throws Exception {
        StringWriter sw = new StringWriter();
        objectMapper.writerWithDefaultPrettyPrinter().writeValue(sw, mapping);
        LOGGER.info(sw.toString());
        Map<String, List<String>> serverToSegmentMapping = new TreeMap<>();
        for (String segment : mapping.keySet()) {
            Map<String, String> serverToStateMap = mapping.get(segment);
            for (String server : serverToStateMap.keySet()) {
                if (!serverToSegmentMapping.containsKey(server)) {
                    serverToSegmentMapping.put(server, new ArrayList<String>());
                }
                serverToSegmentMapping.get(server).add(segment);
            }
        }
        DescriptiveStatistics stats = new DescriptiveStatistics();
        for (String server : serverToSegmentMapping.keySet()) {
            List<String> list = serverToSegmentMapping.get(server);
            LOGGER.info("server " + server + " has " + list.size() + " segments");
            stats.addValue(list.size());
        }
        LOGGER.info("Segment Distrbution stat");
        LOGGER.info(stats.toString());
    }

    public HelixManager getHelixManager() {
        return helixManager;
    }
}