kafka OffsetFetchResponse 源码

  • 2022-10-20
  • 浏览 (417)

kafka OffsetFetchResponse 代码

文件路径:/clients/src/main/java/org/apache/kafka/common/requests/OffsetFetchResponse.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 java.util.Map.Entry;
import java.util.stream.Collectors;
import org.apache.kafka.common.TopicPartition;
import org.apache.kafka.common.message.OffsetFetchResponseData;
import org.apache.kafka.common.message.OffsetFetchResponseData.OffsetFetchResponseGroup;
import org.apache.kafka.common.message.OffsetFetchResponseData.OffsetFetchResponsePartition;
import org.apache.kafka.common.message.OffsetFetchResponseData.OffsetFetchResponsePartitions;
import org.apache.kafka.common.message.OffsetFetchResponseData.OffsetFetchResponseTopic;
import org.apache.kafka.common.message.OffsetFetchResponseData.OffsetFetchResponseTopics;
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.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.Optional;

import static org.apache.kafka.common.record.RecordBatch.NO_PARTITION_LEADER_EPOCH;

/**
 * Possible error codes:
 *
 * - Partition errors:
 *   - {@link Errors#UNKNOWN_TOPIC_OR_PARTITION}
 *   - {@link Errors#TOPIC_AUTHORIZATION_FAILED}
 *   - {@link Errors#UNSTABLE_OFFSET_COMMIT}
 *
 * - Group or coordinator errors:
 *   - {@link Errors#COORDINATOR_LOAD_IN_PROGRESS}
 *   - {@link Errors#COORDINATOR_NOT_AVAILABLE}
 *   - {@link Errors#NOT_COORDINATOR}
 *   - {@link Errors#GROUP_AUTHORIZATION_FAILED}
 */
public class OffsetFetchResponse extends AbstractResponse {
    public static final long INVALID_OFFSET = -1L;
    public static final String NO_METADATA = "";
    public static final PartitionData UNKNOWN_PARTITION = new PartitionData(INVALID_OFFSET,
                                                                            Optional.empty(),
                                                                            NO_METADATA,
                                                                            Errors.UNKNOWN_TOPIC_OR_PARTITION);
    public static final PartitionData UNAUTHORIZED_PARTITION = new PartitionData(INVALID_OFFSET,
                                                                                 Optional.empty(),
                                                                                 NO_METADATA,
                                                                                 Errors.TOPIC_AUTHORIZATION_FAILED);
    private static final List<Errors> PARTITION_ERRORS = Arrays.asList(
        Errors.UNKNOWN_TOPIC_OR_PARTITION, Errors.TOPIC_AUTHORIZATION_FAILED);

    private final OffsetFetchResponseData data;
    private final Errors error;
    private final Map<String, Errors> groupLevelErrors = new HashMap<>();

    public static final class PartitionData {
        public final long offset;
        public final String metadata;
        public final Errors error;
        public final Optional<Integer> leaderEpoch;

        public PartitionData(long offset,
                             Optional<Integer> leaderEpoch,
                             String metadata,
                             Errors error) {
            this.offset = offset;
            this.leaderEpoch = leaderEpoch;
            this.metadata = metadata;
            this.error = error;
        }

        public boolean hasError() {
            return this.error != Errors.NONE;
        }

        @Override
        public boolean equals(Object other) {
            if (!(other instanceof PartitionData))
                return false;
            PartitionData otherPartition = (PartitionData) other;
            return Objects.equals(this.offset, otherPartition.offset)
                   && Objects.equals(this.leaderEpoch, otherPartition.leaderEpoch)
                   && Objects.equals(this.metadata, otherPartition.metadata)
                   && Objects.equals(this.error, otherPartition.error);
        }

        @Override
        public String toString() {
            return "PartitionData("
                       + "offset=" + offset
                       + ", leaderEpoch=" + leaderEpoch.orElse(NO_PARTITION_LEADER_EPOCH)
                       + ", metadata=" + metadata
                       + ", error='" + error.toString()
                       + ")";
        }

        @Override
        public int hashCode() {
            return Objects.hash(offset, leaderEpoch, metadata, error);
        }
    }

    public OffsetFetchResponse(OffsetFetchResponseData data) {
        super(ApiKeys.OFFSET_FETCH);
        this.data = data;
        this.error = null;
    }

    /**
     * Constructor without throttle time.
     * @param error Potential coordinator or group level error code (for api version 2 and later)
     * @param responseData Fetched offset information grouped by topic-partition
     */
    public OffsetFetchResponse(Errors error, Map<TopicPartition, PartitionData> responseData) {
        this(DEFAULT_THROTTLE_TIME, error, responseData);
    }

    /**
     * Constructor with throttle time for version 0 to 7
     * @param throttleTimeMs The time in milliseconds that this response was throttled
     * @param error Potential coordinator or group level error code (for api version 2 and later)
     * @param responseData Fetched offset information grouped by topic-partition
     */
    public OffsetFetchResponse(int throttleTimeMs, Errors error, Map<TopicPartition, PartitionData> responseData) {
        super(ApiKeys.OFFSET_FETCH);
        Map<String, OffsetFetchResponseTopic> offsetFetchResponseTopicMap = new HashMap<>();
        for (Map.Entry<TopicPartition, PartitionData> entry : responseData.entrySet()) {
            String topicName = entry.getKey().topic();
            OffsetFetchResponseTopic topic = offsetFetchResponseTopicMap.getOrDefault(
                topicName, new OffsetFetchResponseTopic().setName(topicName));
            PartitionData partitionData = entry.getValue();
            topic.partitions().add(new OffsetFetchResponsePartition()
                                       .setPartitionIndex(entry.getKey().partition())
                                       .setErrorCode(partitionData.error.code())
                                       .setCommittedOffset(partitionData.offset)
                                       .setCommittedLeaderEpoch(
                                           partitionData.leaderEpoch.orElse(NO_PARTITION_LEADER_EPOCH))
                                       .setMetadata(partitionData.metadata)
            );
            offsetFetchResponseTopicMap.put(topicName, topic);
        }

        this.data = new OffsetFetchResponseData()
            .setTopics(new ArrayList<>(offsetFetchResponseTopicMap.values()))
            .setErrorCode(error.code())
            .setThrottleTimeMs(throttleTimeMs);
        this.error = error;
    }

    /**
     * Constructor with throttle time for version 8 and above.
     * @param throttleTimeMs The time in milliseconds that this response was throttled
     * @param errors Potential coordinator or group level error code
     * @param responseData Fetched offset information grouped by topic-partition and by group
     */
    public OffsetFetchResponse(int throttleTimeMs,
                               Map<String, Errors> errors,
                               Map<String, Map<TopicPartition, PartitionData>> responseData) {
        super(ApiKeys.OFFSET_FETCH);
        List<OffsetFetchResponseGroup> groupList = new ArrayList<>();
        for (Entry<String, Map<TopicPartition, PartitionData>> entry : responseData.entrySet()) {
            String groupName = entry.getKey();
            Map<TopicPartition, PartitionData> partitionDataMap = entry.getValue();
            Map<String, OffsetFetchResponseTopics> offsetFetchResponseTopicsMap = new HashMap<>();
            for (Entry<TopicPartition, PartitionData> partitionEntry : partitionDataMap.entrySet()) {
                String topicName = partitionEntry.getKey().topic();
                OffsetFetchResponseTopics topic =
                    offsetFetchResponseTopicsMap.getOrDefault(topicName,
                        new OffsetFetchResponseTopics().setName(topicName));
                PartitionData partitionData = partitionEntry.getValue();
                topic.partitions().add(new OffsetFetchResponsePartitions()
                    .setPartitionIndex(partitionEntry.getKey().partition())
                    .setErrorCode(partitionData.error.code())
                    .setCommittedOffset(partitionData.offset)
                    .setCommittedLeaderEpoch(
                        partitionData.leaderEpoch.orElse(NO_PARTITION_LEADER_EPOCH))
                    .setMetadata(partitionData.metadata));
                offsetFetchResponseTopicsMap.put(topicName, topic);
            }
            groupList.add(new OffsetFetchResponseGroup()
                .setGroupId(groupName)
                .setTopics(new ArrayList<>(offsetFetchResponseTopicsMap.values()))
                .setErrorCode(errors.get(groupName).code()));
            groupLevelErrors.put(groupName, errors.get(groupName));
        }
        this.data = new OffsetFetchResponseData()
            .setGroups(groupList)
            .setThrottleTimeMs(throttleTimeMs);
        this.error = null;
    }

    public OffsetFetchResponse(OffsetFetchResponseData data, short version) {
        super(ApiKeys.OFFSET_FETCH);
        this.data = data;
        // for version 2 and later use the top-level error code (in ERROR_CODE_KEY_NAME) from the response.
        // for older versions there is no top-level error in the response and all errors are partition errors,
        // so if there is a group or coordinator error at the partition level use that as the top-level error.
        // this way clients can depend on the top-level error regardless of the offset fetch version.
        // we return the error differently starting with version 8, so we will only populate the
        // error field if we are between version 2 and 7. if we are in version 8 or greater, then
        // we will populate the map of group id to error codes.
        if (version < 8) {
            this.error = version >= 2 ? Errors.forCode(data.errorCode()) : topLevelError(data);
        } else {
            for (OffsetFetchResponseGroup group : data.groups()) {
                this.groupLevelErrors.put(group.groupId(), Errors.forCode(group.errorCode()));
            }
            this.error = null;
        }
    }

    private static Errors topLevelError(OffsetFetchResponseData data) {
        for (OffsetFetchResponseTopic topic : data.topics()) {
            for (OffsetFetchResponsePartition partition : topic.partitions()) {
                Errors partitionError = Errors.forCode(partition.errorCode());
                if (partitionError != Errors.NONE && !PARTITION_ERRORS.contains(partitionError)) {
                    return partitionError;
                }
            }
        }
        return Errors.NONE;
    }

    @Override
    public int throttleTimeMs() {
        return data.throttleTimeMs();
    }

    @Override
    public void maybeSetThrottleTimeMs(int throttleTimeMs) {
        data.setThrottleTimeMs(throttleTimeMs);
    }

    public boolean hasError() {
        return error != Errors.NONE;
    }

    public boolean groupHasError(String groupId) {
        Errors error = groupLevelErrors.get(groupId);
        if (error == null) {
            return this.error != null && this.error != Errors.NONE;
        }
        return error != Errors.NONE;
    }

    public Errors error() {
        return error;
    }

    public Errors groupLevelError(String groupId) {
        if (error != null) {
            return error;
        }
        return groupLevelErrors.get(groupId);
    }

    @Override
    public Map<Errors, Integer> errorCounts() {
        Map<Errors, Integer> counts = new HashMap<>();
        if (!groupLevelErrors.isEmpty()) {
            // built response with v8 or above
            for (Map.Entry<String, Errors> entry : groupLevelErrors.entrySet()) {
                updateErrorCounts(counts, entry.getValue());
            }
            for (OffsetFetchResponseGroup group : data.groups()) {
                group.topics().forEach(topic ->
                    topic.partitions().forEach(partition ->
                        updateErrorCounts(counts, Errors.forCode(partition.errorCode()))));
            }
        } else {
            // built response with v0-v7
            updateErrorCounts(counts, error);
            data.topics().forEach(topic ->
                topic.partitions().forEach(partition ->
                    updateErrorCounts(counts, Errors.forCode(partition.errorCode()))));
        }
        return counts;
    }

    // package-private for testing purposes
    Map<TopicPartition, PartitionData> responseDataV0ToV7() {
        Map<TopicPartition, PartitionData> responseData = new HashMap<>();
        for (OffsetFetchResponseTopic topic : data.topics()) {
            for (OffsetFetchResponsePartition partition : topic.partitions()) {
                responseData.put(new TopicPartition(topic.name(), partition.partitionIndex()),
                                 new PartitionData(partition.committedOffset(),
                                                   RequestUtils.getLeaderEpoch(partition.committedLeaderEpoch()),
                                                   partition.metadata(),
                                                   Errors.forCode(partition.errorCode()))
                );
            }
        }
        return responseData;
    }

    private Map<TopicPartition, PartitionData> buildResponseData(String groupId) {
        Map<TopicPartition, PartitionData> responseData = new HashMap<>();
        OffsetFetchResponseGroup group = data
            .groups()
            .stream()
            .filter(g -> g.groupId().equals(groupId))
            .collect(Collectors.toList())
            .get(0);
        for (OffsetFetchResponseTopics topic : group.topics()) {
            for (OffsetFetchResponsePartitions partition : topic.partitions()) {
                responseData.put(new TopicPartition(topic.name(), partition.partitionIndex()),
                    new PartitionData(partition.committedOffset(),
                        RequestUtils.getLeaderEpoch(partition.committedLeaderEpoch()),
                        partition.metadata(),
                        Errors.forCode(partition.errorCode()))
                );
            }
        }
        return responseData;
    }

    public Map<TopicPartition, PartitionData> partitionDataMap(String groupId) {
        if (groupLevelErrors.isEmpty()) {
            return responseDataV0ToV7();
        }
        return buildResponseData(groupId);
    }

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

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

    @Override
    public boolean shouldClientThrottle(short version) {
        return version >= 4;
    }
}

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