kafka Cluster 源码

  • 2022-10-20
  • 浏览 (549)

kafka Cluster 代码

文件路径:/clients/src/main/java/org/apache/kafka/common/Cluster.java

/*
 * 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.kafka.common;

import java.net.InetSocketAddress;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.Optional;
import java.util.Set;

/**
 * An immutable representation of a subset of the nodes, topics, and partitions in the Kafka cluster.
 */
public final class Cluster {

    private final boolean isBootstrapConfigured;
    private final List<Node> nodes;
    private final Set<String> unauthorizedTopics;
    private final Set<String> invalidTopics;
    private final Set<String> internalTopics;
    private final Node controller;
    private final Map<TopicPartition, PartitionInfo> partitionsByTopicPartition;
    private final Map<String, List<PartitionInfo>> partitionsByTopic;
    private final Map<String, List<PartitionInfo>> availablePartitionsByTopic;
    private final Map<Integer, List<PartitionInfo>> partitionsByNode;
    private final Map<Integer, Node> nodesById;
    private final ClusterResource clusterResource;
    private final Map<String, Uuid> topicIds;
    private final Map<Uuid, String> topicNames;

    /**
     * Create a new cluster with the given id, nodes and partitions
     * @param nodes The nodes in the cluster
     * @param partitions Information about a subset of the topic-partitions this cluster hosts
     */
    public Cluster(String clusterId,
                   Collection<Node> nodes,
                   Collection<PartitionInfo> partitions,
                   Set<String> unauthorizedTopics,
                   Set<String> internalTopics) {
        this(clusterId, false, nodes, partitions, unauthorizedTopics, Collections.emptySet(), internalTopics, null, Collections.emptyMap());
    }

    /**
     * Create a new cluster with the given id, nodes and partitions
     * @param nodes The nodes in the cluster
     * @param partitions Information about a subset of the topic-partitions this cluster hosts
     */
    public Cluster(String clusterId,
                   Collection<Node> nodes,
                   Collection<PartitionInfo> partitions,
                   Set<String> unauthorizedTopics,
                   Set<String> internalTopics,
                   Node controller) {
        this(clusterId, false, nodes, partitions, unauthorizedTopics, Collections.emptySet(), internalTopics, controller, Collections.emptyMap());
    }

    /**
     * Create a new cluster with the given id, nodes and partitions
     * @param nodes The nodes in the cluster
     * @param partitions Information about a subset of the topic-partitions this cluster hosts
     */
    public Cluster(String clusterId,
                   Collection<Node> nodes,
                   Collection<PartitionInfo> partitions,
                   Set<String> unauthorizedTopics,
                   Set<String> invalidTopics,
                   Set<String> internalTopics,
                   Node controller) {
        this(clusterId, false, nodes, partitions, unauthorizedTopics, invalidTopics, internalTopics, controller, Collections.emptyMap());
    }

    /**
     * Create a new cluster with the given id, nodes, partitions and topicIds
     * @param nodes The nodes in the cluster
     * @param partitions Information about a subset of the topic-partitions this cluster hosts
     */
    public Cluster(String clusterId,
                   Collection<Node> nodes,
                   Collection<PartitionInfo> partitions,
                   Set<String> unauthorizedTopics,
                   Set<String> invalidTopics,
                   Set<String> internalTopics,
                   Node controller,
                   Map<String, Uuid> topicIds) {
        this(clusterId, false, nodes, partitions, unauthorizedTopics, invalidTopics, internalTopics, controller, topicIds);
    }

    private Cluster(String clusterId,
                    boolean isBootstrapConfigured,
                    Collection<Node> nodes,
                    Collection<PartitionInfo> partitions,
                    Set<String> unauthorizedTopics,
                    Set<String> invalidTopics,
                    Set<String> internalTopics,
                    Node controller,
                    Map<String, Uuid> topicIds) {
        this.isBootstrapConfigured = isBootstrapConfigured;
        this.clusterResource = new ClusterResource(clusterId);
        // make a randomized, unmodifiable copy of the nodes
        List<Node> copy = new ArrayList<>(nodes);
        Collections.shuffle(copy);
        this.nodes = Collections.unmodifiableList(copy);

        // Index the nodes for quick lookup
        Map<Integer, Node> tmpNodesById = new HashMap<>();
        Map<Integer, List<PartitionInfo>> tmpPartitionsByNode = new HashMap<>(nodes.size());
        for (Node node : nodes) {
            tmpNodesById.put(node.id(), node);
            // Populate the map here to make it easy to add the partitions per node efficiently when iterating over
            // the partitions
            tmpPartitionsByNode.put(node.id(), new ArrayList<>());
        }
        this.nodesById = Collections.unmodifiableMap(tmpNodesById);

        // index the partition infos by topic, topic+partition, and node
        // note that this code is performance sensitive if there are a large number of partitions so we are careful
        // to avoid unnecessary work
        Map<TopicPartition, PartitionInfo> tmpPartitionsByTopicPartition = new HashMap<>(partitions.size());
        Map<String, List<PartitionInfo>> tmpPartitionsByTopic = new HashMap<>();
        for (PartitionInfo p : partitions) {
            tmpPartitionsByTopicPartition.put(new TopicPartition(p.topic(), p.partition()), p);
            tmpPartitionsByTopic.computeIfAbsent(p.topic(), topic -> new ArrayList<>()).add(p);

            // The leader may not be known
            if (p.leader() == null || p.leader().isEmpty())
                continue;

            // If it is known, its node information should be available
            List<PartitionInfo> partitionsForNode = Objects.requireNonNull(tmpPartitionsByNode.get(p.leader().id()));
            partitionsForNode.add(p);
        }

        // Update the values of `tmpPartitionsByNode` to contain unmodifiable lists
        for (Map.Entry<Integer, List<PartitionInfo>> entry : tmpPartitionsByNode.entrySet()) {
            tmpPartitionsByNode.put(entry.getKey(), Collections.unmodifiableList(entry.getValue()));
        }

        // Populate `tmpAvailablePartitionsByTopic` and update the values of `tmpPartitionsByTopic` to contain
        // unmodifiable lists
        Map<String, List<PartitionInfo>> tmpAvailablePartitionsByTopic = new HashMap<>(tmpPartitionsByTopic.size());
        for (Map.Entry<String, List<PartitionInfo>> entry : tmpPartitionsByTopic.entrySet()) {
            String topic = entry.getKey();
            List<PartitionInfo> partitionsForTopic = Collections.unmodifiableList(entry.getValue());
            tmpPartitionsByTopic.put(topic, partitionsForTopic);
            // Optimise for the common case where all partitions are available
            boolean foundUnavailablePartition = partitionsForTopic.stream().anyMatch(p -> p.leader() == null);
            List<PartitionInfo> availablePartitionsForTopic;
            if (foundUnavailablePartition) {
                availablePartitionsForTopic = new ArrayList<>(partitionsForTopic.size());
                for (PartitionInfo p : partitionsForTopic) {
                    if (p.leader() != null)
                        availablePartitionsForTopic.add(p);
                }
                availablePartitionsForTopic = Collections.unmodifiableList(availablePartitionsForTopic);
            } else {
                availablePartitionsForTopic = partitionsForTopic;
            }
            tmpAvailablePartitionsByTopic.put(topic, availablePartitionsForTopic);
        }

        this.partitionsByTopicPartition = Collections.unmodifiableMap(tmpPartitionsByTopicPartition);
        this.partitionsByTopic = Collections.unmodifiableMap(tmpPartitionsByTopic);
        this.availablePartitionsByTopic = Collections.unmodifiableMap(tmpAvailablePartitionsByTopic);
        this.partitionsByNode = Collections.unmodifiableMap(tmpPartitionsByNode);
        this.topicIds = Collections.unmodifiableMap(topicIds);
        Map<Uuid, String> tmpTopicNames = new HashMap<>();
        topicIds.forEach((key, value) -> tmpTopicNames.put(value, key));
        this.topicNames = Collections.unmodifiableMap(tmpTopicNames);

        this.unauthorizedTopics = Collections.unmodifiableSet(unauthorizedTopics);
        this.invalidTopics = Collections.unmodifiableSet(invalidTopics);
        this.internalTopics = Collections.unmodifiableSet(internalTopics);
        this.controller = controller;
    }

    /**
     * Create an empty cluster instance with no nodes and no topic-partitions.
     */
    public static Cluster empty() {
        return new Cluster(null, new ArrayList<>(0), new ArrayList<>(0), Collections.emptySet(),
            Collections.emptySet(), null);
    }

    /**
     * Create a "bootstrap" cluster using the given list of host/ports
     * @param addresses The addresses
     * @return A cluster for these hosts/ports
     */
    public static Cluster bootstrap(List<InetSocketAddress> addresses) {
        List<Node> nodes = new ArrayList<>();
        int nodeId = -1;
        for (InetSocketAddress address : addresses)
            nodes.add(new Node(nodeId--, address.getHostString(), address.getPort()));
        return new Cluster(null, true, nodes, new ArrayList<>(0),
            Collections.emptySet(), Collections.emptySet(), Collections.emptySet(), null, Collections.emptyMap());
    }

    /**
     * Return a copy of this cluster combined with `partitions`.
     */
    public Cluster withPartitions(Map<TopicPartition, PartitionInfo> partitions) {
        Map<TopicPartition, PartitionInfo> combinedPartitions = new HashMap<>(this.partitionsByTopicPartition);
        combinedPartitions.putAll(partitions);
        return new Cluster(clusterResource.clusterId(), this.nodes, combinedPartitions.values(),
                new HashSet<>(this.unauthorizedTopics), new HashSet<>(this.invalidTopics),
                new HashSet<>(this.internalTopics), this.controller);
    }

    /**
     * @return The known set of nodes
     */
    public List<Node> nodes() {
        return this.nodes;
    }

    /**
     * Get the node by the node id (or null if the node is not online or does not exist)
     * @param id The id of the node
     * @return The node, or null if the node is not online or does not exist
     */
    public Node nodeById(int id) {
        return this.nodesById.get(id);
    }

    /**
     * Get the node by node id if the replica for the given partition is online
     * @param partition
     * @param id
     * @return the node
     */
    public Optional<Node> nodeIfOnline(TopicPartition partition, int id) {
        Node node = nodeById(id);
        PartitionInfo partitionInfo = partition(partition);
        if (node != null && partitionInfo != null && !Arrays.asList(partitionInfo.offlineReplicas()).contains(node)) {
            return Optional.of(node);
        } else {
            return Optional.empty();
        }
    }

    /**
     * Get the current leader for the given topic-partition
     * @param topicPartition The topic and partition we want to know the leader for
     * @return The node that is the leader for this topic-partition, or null if there is currently no leader
     */
    public Node leaderFor(TopicPartition topicPartition) {
        PartitionInfo info = partitionsByTopicPartition.get(topicPartition);
        if (info == null)
            return null;
        else
            return info.leader();
    }

    /**
     * Get the metadata for the specified partition
     * @param topicPartition The topic and partition to fetch info for
     * @return The metadata about the given topic and partition, or null if none is found
     */
    public PartitionInfo partition(TopicPartition topicPartition) {
        return partitionsByTopicPartition.get(topicPartition);
    }

    /**
     * Get the list of partitions for this topic
     * @param topic The topic name
     * @return A list of partitions
     */
    public List<PartitionInfo> partitionsForTopic(String topic) {
        return partitionsByTopic.getOrDefault(topic, Collections.emptyList());
    }

    /**
     * Get the number of partitions for the given topic.
     * @param topic The topic to get the number of partitions for
     * @return The number of partitions or null if there is no corresponding metadata
     */
    public Integer partitionCountForTopic(String topic) {
        List<PartitionInfo> partitions = this.partitionsByTopic.get(topic);
        return partitions == null ? null : partitions.size();
    }

    /**
     * Get the list of available partitions for this topic
     * @param topic The topic name
     * @return A list of partitions
     */
    public List<PartitionInfo> availablePartitionsForTopic(String topic) {
        return availablePartitionsByTopic.getOrDefault(topic, Collections.emptyList());
    }

    /**
     * Get the list of partitions whose leader is this node
     * @param nodeId The node id
     * @return A list of partitions
     */
    public List<PartitionInfo> partitionsForNode(int nodeId) {
        return partitionsByNode.getOrDefault(nodeId, Collections.emptyList());
    }

    /**
     * Get all topics.
     * @return a set of all topics
     */
    public Set<String> topics() {
        return partitionsByTopic.keySet();
    }

    public Set<String> unauthorizedTopics() {
        return unauthorizedTopics;
    }

    public Set<String> invalidTopics() {
        return invalidTopics;
    }

    public Set<String> internalTopics() {
        return internalTopics;
    }

    public boolean isBootstrapConfigured() {
        return isBootstrapConfigured;
    }

    public ClusterResource clusterResource() {
        return clusterResource;
    }

    public Node controller() {
        return controller;
    }

    public Collection<Uuid> topicIds() {
        return topicIds.values();
    }

    public Uuid topicId(String topic) {
        return topicIds.getOrDefault(topic, Uuid.ZERO_UUID);
    }

    public String topicName(Uuid topicId) {
        return topicNames.get(topicId);
    }

    @Override
    public String toString() {
        return "Cluster(id = " + clusterResource.clusterId() + ", nodes = " + this.nodes +
            ", partitions = " + this.partitionsByTopicPartition.values() + ", controller = " + controller + ")";
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        Cluster cluster = (Cluster) o;
        return isBootstrapConfigured == cluster.isBootstrapConfigured &&
                Objects.equals(nodes, cluster.nodes) &&
                Objects.equals(unauthorizedTopics, cluster.unauthorizedTopics) &&
                Objects.equals(invalidTopics, cluster.invalidTopics) &&
                Objects.equals(internalTopics, cluster.internalTopics) &&
                Objects.equals(controller, cluster.controller) &&
                Objects.equals(partitionsByTopicPartition, cluster.partitionsByTopicPartition) &&
                Objects.equals(clusterResource, cluster.clusterResource);
    }

    @Override
    public int hashCode() {
        return Objects.hash(isBootstrapConfigured, nodes, unauthorizedTopics, invalidTopics, internalTopics, controller,
                partitionsByTopicPartition, clusterResource);
    }
}

相关信息

kafka 源码目录

相关文章

kafka ClusterResource 源码

kafka ClusterResourceListener 源码

kafka Configurable 源码

kafka ConsumerGroupState 源码

kafka ElectionType 源码

kafka Endpoint 源码

kafka InvalidRecordException 源码

kafka IsolationLevel 源码

kafka KafkaException 源码

kafka KafkaFuture 源码

0  赞