com.uber.stream.kafka.mirrormaker.common.utils.HelixUtils.java Source code

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/*
 * Copyright (C) 2015-2019 Uber Technologies, Inc. (streaming-data@uber.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.uber.stream.kafka.mirrormaker.common.utils;

import com.google.common.collect.ImmutableList;
import com.uber.stream.kafka.mirrormaker.common.Constants;
import com.uber.stream.kafka.mirrormaker.common.core.InstanceTopicPartitionHolder;
import com.uber.stream.kafka.mirrormaker.common.core.KafkaBrokerTopicObserver;
import com.uber.stream.kafka.mirrormaker.common.core.OnlineOfflineStateModel;
import com.uber.stream.kafka.mirrormaker.common.core.TopicPartition;
import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.PriorityQueue;
import java.util.Set;
import org.apache.commons.lang.StringUtils;
import org.apache.helix.HelixAdmin;
import org.apache.helix.HelixDataAccessor;
import org.apache.helix.HelixManager;
import org.apache.helix.PropertyKey;
import org.apache.helix.PropertyPathConfig;
import org.apache.helix.PropertyType;
import org.apache.helix.ZNRecord;
import org.apache.helix.manager.zk.ZkBaseDataAccessor;
import org.apache.helix.model.IdealState;
import org.apache.helix.model.InstanceConfig;
import org.apache.helix.model.builder.CustomModeISBuilder;
import org.apache.helix.store.zk.ZkHelixPropertyStore;

public class HelixUtils {

    private static final String BLACKLIST_TAG = "blacklisted";

    public static String getAbsoluteZkPathForHelix(String zkBaseUrl) {
        zkBaseUrl = StringUtils.chomp(zkBaseUrl, "/");
        return zkBaseUrl;
    }

    public static ZkHelixPropertyStore<ZNRecord> getZkPropertyStore(HelixManager helixManager, String clusterName) {
        ZkBaseDataAccessor<ZNRecord> baseAccessor = (ZkBaseDataAccessor<ZNRecord>) helixManager
                .getHelixDataAccessor().getBaseDataAccessor();
        String propertyStorePath = PropertyPathConfig.getPath(PropertyType.PROPERTYSTORE, clusterName);

        ZkHelixPropertyStore<ZNRecord> propertyStore = new ZkHelixPropertyStore<ZNRecord>(baseAccessor,
                propertyStorePath, Arrays.asList(propertyStorePath));

        return propertyStore;
    }

    public static Map<String, String> getInstanceToHostnameMap(HelixManager helixManager) {
        List<String> instances = liveInstances(helixManager);
        HashMap<String, String> retVal = new HashMap<>(instances.size());
        for (String instance : instances) {
            InstanceConfig config = helixManager.getConfigAccessor()
                    .getInstanceConfig(helixManager.getClusterName(), instance);
            if (config != null) {
                retVal.put(instance, config.getHostName());
            }
        }
        return retVal;
    }

    public static List<String> liveInstances(HelixManager helixManager) {
        HelixDataAccessor helixDataAccessor = helixManager.getHelixDataAccessor();
        PropertyKey liveInstancesKey = helixDataAccessor.keyBuilder().liveInstances();
        return ImmutableList.copyOf(helixDataAccessor.getChildNames(liveInstancesKey));
    }

    public static List<String> blacklistedInstances(HelixManager helixManager) {
        return helixManager.getClusterManagmentTool().getInstancesInClusterWithTag(helixManager.getClusterName(),
                BLACKLIST_TAG);
    }

    private static String getSrcFromRoute(String route) {
        return route.substring(1, route.indexOf("@", 1));
    }

    private static String getPipelineFromRoute(String route) {
        return route.substring(0, route.lastIndexOf("@"));
    }

    public static Map<String, Set<TopicPartition>> getInstanceToTopicPartitionsMap(HelixManager helixManager) {
        return getInstanceToTopicPartitionsMap(helixManager, null);
    }

    /**
     * From IdealStates.
     *
     * @return InstanceToNumTopicPartitionMap
     */
    public static Map<String, Set<TopicPartition>> getInstanceToTopicPartitionsMap(HelixManager helixManager,
            Map<String, KafkaBrokerTopicObserver> clusterToObserverMap) {
        Map<String, Set<TopicPartition>> instanceToNumTopicPartitionMap = new HashMap<>();
        HelixAdmin helixAdmin = helixManager.getClusterManagmentTool();
        String helixClusterName = helixManager.getClusterName();
        for (String topic : helixAdmin.getResourcesInCluster(helixClusterName)) {
            IdealState is = helixAdmin.getResourceIdealState(helixClusterName, topic);
            for (String partition : is.getPartitionSet()) {
                TopicPartition tpi;
                if (partition.startsWith("@")) {
                    // topic
                    if (clusterToObserverMap != null) {
                        // TODO: topic not existed
                        try {
                            int trueNumPartition = clusterToObserverMap.get(getSrcFromRoute(partition))
                                    .getTopicPartitionWithRefresh(topic).getPartition();
                            tpi = new TopicPartition(topic, trueNumPartition, partition);
                        } catch (Exception e) {
                            tpi = new TopicPartition(topic, -1, partition);
                        }
                    } else {
                        tpi = new TopicPartition(topic, -1, partition);
                    }
                } else {
                    // route
                    tpi = new TopicPartition(topic, Integer.parseInt(partition));
                }
                for (String instance : is.getInstanceSet(partition)) {
                    instanceToNumTopicPartitionMap.putIfAbsent(instance, new HashSet<>());
                    instanceToNumTopicPartitionMap.get(instance).add(tpi);
                }
            }
        }
        return instanceToNumTopicPartitionMap;
    }

    public static IdealState buildCustomIdealStateFor(String topicName, int numTopicPartitions,
            PriorityQueue<InstanceTopicPartitionHolder> instanceToNumServingTopicPartitionMap) {

        final CustomModeISBuilder customModeIdealStateBuilder = new CustomModeISBuilder(topicName);

        customModeIdealStateBuilder.setStateModel(OnlineOfflineStateModel.name).setNumPartitions(numTopicPartitions)
                .setNumReplica(1).setMaxPartitionsPerNode(numTopicPartitions);

        for (int i = 0; i < numTopicPartitions; ++i) {
            synchronized (instanceToNumServingTopicPartitionMap) {
                InstanceTopicPartitionHolder liveInstance = instanceToNumServingTopicPartitionMap.poll();
                customModeIdealStateBuilder.assignInstanceAndState(Integer.toString(i),
                        liveInstance.getInstanceName(), "ONLINE");
                liveInstance.addTopicPartition(new TopicPartition(topicName, i));
                instanceToNumServingTopicPartitionMap.add(liveInstance);
            }
        }
        return customModeIdealStateBuilder.build();
    }

    public static Map<String, IdealState> getIdealStatesFromAssignment(
            Set<InstanceTopicPartitionHolder> newAssignment, Set<TopicPartition> blacklistedTopicPartitions) {
        Map<String, CustomModeISBuilder> idealStatesBuilderMap = new HashMap<>();
        for (InstanceTopicPartitionHolder instance : newAssignment) {
            for (TopicPartition tpi : instance.getServingTopicPartitionSet()) {
                String topicName = tpi.getTopic();
                String partition = Integer.toString(tpi.getPartition());
                if (!idealStatesBuilderMap.containsKey(topicName)) {
                    final CustomModeISBuilder customModeIdealStateBuilder = new CustomModeISBuilder(topicName);
                    customModeIdealStateBuilder.setStateModel(OnlineOfflineStateModel.name).setNumReplica(1);

                    idealStatesBuilderMap.put(topicName, customModeIdealStateBuilder);
                }
                String state = Constants.HELIX_ONLINE_STATE;
                if (blacklistedTopicPartitions.contains(tpi)) {
                    state = Constants.HELIX_OFFLINE_STATE;
                }
                idealStatesBuilderMap.get(topicName).assignInstanceAndState(partition, instance.getInstanceName(),
                        state);
            }
        }
        Map<String, IdealState> idealStatesMap = new HashMap<>();
        for (String topic : idealStatesBuilderMap.keySet()) {
            IdealState idealState = idealStatesBuilderMap.get(topic).build();
            idealState.setMaxPartitionsPerInstance(idealState.getPartitionSet().size());
            idealState.setNumPartitions(idealState.getPartitionSet().size());
            idealStatesMap.put(topic, idealState);
        }
        return idealStatesMap;
    }

    public static Set<TopicPartition> getUnassignedPartitions(HelixManager helixManager) {
        Set<TopicPartition> unassignedPartitions = new HashSet<TopicPartition>();
        HelixAdmin helixAdmin = helixManager.getClusterManagmentTool();
        String helixClusterName = helixManager.getClusterName();
        for (String topic : helixAdmin.getResourcesInCluster(helixClusterName)) {
            IdealState is = helixAdmin.getResourceIdealState(helixClusterName, topic);
            int numPartitions = is.getNumPartitions();
            for (int partition = 0; partition < numPartitions; ++partition) {
                if (is.getInstanceSet(Integer.toString(partition)).isEmpty()) {
                    TopicPartition tpi = new TopicPartition(topic, partition);
                    unassignedPartitions.add(tpi);
                }
            }
        }
        return unassignedPartitions;
    }

}