kafka MetadataRequest 源码

  • 2022-10-20
  • 浏览 (525)

kafka MetadataRequest 代码

文件路径:/clients/src/main/java/org/apache/kafka/common/requests/MetadataRequest.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.requests;

import org.apache.kafka.common.Uuid;
import org.apache.kafka.common.errors.UnsupportedVersionException;
import org.apache.kafka.common.message.MetadataRequestData;
import org.apache.kafka.common.message.MetadataRequestData.MetadataRequestTopic;
import org.apache.kafka.common.message.MetadataResponseData;
import org.apache.kafka.common.protocol.ApiKeys;
import org.apache.kafka.common.protocol.ByteBufferAccessor;
import org.apache.kafka.common.protocol.Errors;

import java.nio.ByteBuffer;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.stream.Collectors;

public class MetadataRequest extends AbstractRequest {

    public static class Builder extends AbstractRequest.Builder<MetadataRequest> {
        private static final MetadataRequestData ALL_TOPICS_REQUEST_DATA = new MetadataRequestData().
            setTopics(null).setAllowAutoTopicCreation(true);

        private final MetadataRequestData data;

        public Builder(MetadataRequestData data) {
            super(ApiKeys.METADATA);
            this.data = data;
        }

        public Builder(List<String> topics, boolean allowAutoTopicCreation, short allowedVersion) {
            this(topics, allowAutoTopicCreation, allowedVersion, allowedVersion);
        }

        public Builder(List<String> topics, boolean allowAutoTopicCreation, short minVersion, short maxVersion) {
            super(ApiKeys.METADATA, minVersion, maxVersion);
            MetadataRequestData data = new MetadataRequestData();
            if (topics == null)
                data.setTopics(null);
            else {
                topics.forEach(topic -> data.topics().add(new MetadataRequestTopic().setName(topic)));
            }

            data.setAllowAutoTopicCreation(allowAutoTopicCreation);
            this.data = data;
        }

        public Builder(List<String> topics, boolean allowAutoTopicCreation) {
            this(topics, allowAutoTopicCreation, ApiKeys.METADATA.oldestVersion(),  ApiKeys.METADATA.latestVersion());
        }

        public Builder(List<Uuid> topicIds) {
            super(ApiKeys.METADATA, ApiKeys.METADATA.oldestVersion(), ApiKeys.METADATA.latestVersion());
            MetadataRequestData data = new MetadataRequestData();
            if (topicIds == null)
                data.setTopics(null);
            else {
                topicIds.forEach(topicId -> data.topics().add(new MetadataRequestTopic().setTopicId(topicId)));
            }

            // It's impossible to create topic with topicId
            data.setAllowAutoTopicCreation(false);
            this.data = data;
        }

        public static Builder allTopics() {
            // This never causes auto-creation, but we set the boolean to true because that is the default value when
            // deserializing V2 and older. This way, the value is consistent after serialization and deserialization.
            return new Builder(ALL_TOPICS_REQUEST_DATA);
        }

        public boolean emptyTopicList() {
            return data.topics().isEmpty();
        }

        public boolean isAllTopics() {
            return data.topics() == null;
        }

        public List<String> topics() {
            return data.topics()
                .stream()
                .map(MetadataRequestTopic::name)
                .collect(Collectors.toList());
        }

        @Override
        public MetadataRequest build(short version) {
            if (version < 1)
                throw new UnsupportedVersionException("MetadataRequest versions older than 1 are not supported.");
            if (!data.allowAutoTopicCreation() && version < 4)
                throw new UnsupportedVersionException("MetadataRequest versions older than 4 don't support the " +
                        "allowAutoTopicCreation field");
            if (data.topics() != null) {
                data.topics().forEach(topic -> {
                    if (topic.name() == null && version < 12)
                        throw new UnsupportedVersionException("MetadataRequest version " + version +
                                " does not support null topic names.");
                    if (!Uuid.ZERO_UUID.equals(topic.topicId()) && version < 12)
                        throw new UnsupportedVersionException("MetadataRequest version " + version +
                            " does not support non-zero topic IDs.");
                });
            }
            return new MetadataRequest(data, version);
        }

        @Override
        public String toString() {
            return data.toString();
        }
    }

    private final MetadataRequestData data;

    public MetadataRequest(MetadataRequestData data, short version) {
        super(ApiKeys.METADATA, version);
        this.data = data;
    }

    @Override
    public MetadataRequestData data() {
        return data;
    }

    @Override
    public AbstractResponse getErrorResponse(int throttleTimeMs, Throwable e) {
        Errors error = Errors.forException(e);
        MetadataResponseData responseData = new MetadataResponseData();
        if (data.topics() != null) {
            for (MetadataRequestTopic topic : data.topics()) {
                // the response does not allow null, so convert to empty string if necessary
                String topicName = topic.name() == null ? "" : topic.name();
                responseData.topics().add(new MetadataResponseData.MetadataResponseTopic()
                    .setName(topicName)
                    .setTopicId(topic.topicId())
                    .setErrorCode(error.code())
                    .setIsInternal(false)
                    .setPartitions(Collections.emptyList()));
            }
        }

        responseData.setThrottleTimeMs(throttleTimeMs);
        return new MetadataResponse(responseData, true);
    }

    public boolean isAllTopics() {
        return (data.topics() == null) ||
            (data.topics().isEmpty() && version() == 0); // In version 0, an empty topic list indicates
                                                         // "request metadata for all topics."
    }

    public List<String> topics() {
        if (isAllTopics()) // In version 0, we return null for empty topic list
            return null;
        else
            return data.topics()
                .stream()
                .map(MetadataRequestTopic::name)
                .collect(Collectors.toList());
    }

    public List<Uuid> topicIds() {
        if (isAllTopics())
            return Collections.emptyList();
        else if (version() < 10)
            return Collections.emptyList();
        else
            return data.topics()
                    .stream()
                    .map(MetadataRequestTopic::topicId)
                    .collect(Collectors.toList());
    }

    public boolean allowAutoTopicCreation() {
        return data.allowAutoTopicCreation();
    }

    public static MetadataRequest parse(ByteBuffer buffer, short version) {
        return new MetadataRequest(new MetadataRequestData(new ByteBufferAccessor(buffer), version), version);
    }

    public static List<MetadataRequestTopic> convertToMetadataRequestTopic(final Collection<String> topics) {
        return topics.stream().map(topic -> new MetadataRequestTopic()
            .setName(topic))
            .collect(Collectors.toList());
    }

    public static List<MetadataRequestTopic> convertTopicIdsToMetadataRequestTopic(final Collection<Uuid> topicIds) {
        return topicIds.stream().map(topicId -> new MetadataRequestTopic()
                .setTopicId(topicId))
                .collect(Collectors.toList());
    }
}

相关信息

kafka 源码目录

相关文章

kafka AbstractControlRequest 源码

kafka AbstractRequest 源码

kafka AbstractRequestResponse 源码

kafka AbstractResponse 源码

kafka AddOffsetsToTxnRequest 源码

kafka AddOffsetsToTxnResponse 源码

kafka AddPartitionsToTxnRequest 源码

kafka AddPartitionsToTxnResponse 源码

kafka AllocateProducerIdsRequest 源码

kafka AllocateProducerIdsResponse 源码

0  赞