kafka ControlRecordType 源码

kafka ControlRecordType 代码

文件路径：/clients/src/main/java/org/apache/kafka/common/record/ControlRecordType.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.record;

import org.apache.kafka.common.InvalidRecordException;
import org.apache.kafka.common.protocol.types.Field;
import org.apache.kafka.common.protocol.types.Schema;
import org.apache.kafka.common.protocol.types.Struct;
import org.apache.kafka.common.protocol.types.Type;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.nio.ByteBuffer;

/**
 * Control records specify a schema for the record key which includes a version and type:
 *
 * Key => Version Type
 *   Version => Int16
 *   Type => Int16
 *
 * In the future, the version can be bumped to indicate a new schema, but it must be backwards compatible
 * with the current schema. In general, this means we can add new fields, but we cannot remove old ones.
 *
 * Note that control records are not considered for compaction by the log cleaner.
 *
 * The schema for the value field is left to the control record type to specify.
 */
public enum ControlRecordType {
    ABORT((short) 0),
    COMMIT((short) 1),

    // Raft quorum related control messages.
    LEADER_CHANGE((short) 2),
    SNAPSHOT_HEADER((short) 3),
    SNAPSHOT_FOOTER((short) 4),

    // UNKNOWN is used to indicate a control type which the client is not aware of and should be ignored
    UNKNOWN((short) -1);

    private static final Logger log = LoggerFactory.getLogger(ControlRecordType.class);

    static final short CURRENT_CONTROL_RECORD_KEY_VERSION = 0;
    static final int CURRENT_CONTROL_RECORD_KEY_SIZE = 4;
    private static final Schema CONTROL_RECORD_KEY_SCHEMA_VERSION_V0 = new Schema(
            new Field("version", Type.INT16),
            new Field("type", Type.INT16));

    final short type;

    ControlRecordType(short type) {
        this.type = type;
    }

    public Struct recordKey() {
        if (this == UNKNOWN)
            throw new IllegalArgumentException("Cannot serialize UNKNOWN control record type");

        Struct struct = new Struct(CONTROL_RECORD_KEY_SCHEMA_VERSION_V0);
        struct.set("version", CURRENT_CONTROL_RECORD_KEY_VERSION);
        struct.set("type", type);
        return struct;
    }

    public static short parseTypeId(ByteBuffer key) {
        if (key.remaining() < CURRENT_CONTROL_RECORD_KEY_SIZE)
            throw new InvalidRecordException("Invalid value size found for end control record key. Must have " +
                    "at least " + CURRENT_CONTROL_RECORD_KEY_SIZE + " bytes, but found only " + key.remaining());

        short version = key.getShort(0);
        if (version < 0)
            throw new InvalidRecordException("Invalid version found for control record: " + version +
                    ". May indicate data corruption");

        if (version != CURRENT_CONTROL_RECORD_KEY_VERSION)
            log.debug("Received unknown control record key version {}. Parsing as version {}", version,
                    CURRENT_CONTROL_RECORD_KEY_VERSION);
        return key.getShort(2);
    }

    public static ControlRecordType fromTypeId(short typeId) {
        switch (typeId) {
            case 0:
                return ABORT;
            case 1:
                return COMMIT;
            case 2:
                return LEADER_CHANGE;
            case 3:
                return SNAPSHOT_HEADER;
            case 4:
                return SNAPSHOT_FOOTER;

            default:
                return UNKNOWN;
        }
    }

    public static ControlRecordType parse(ByteBuffer key) {
        return fromTypeId(parseTypeId(key));
    }
}

相关信息

kafka 源码目录

相关文章

kafka AbstractLegacyRecordBatch 源码

kafka AbstractRecordBatch 源码

kafka AbstractRecords 源码

kafka BaseRecords 源码

kafka ByteBufferLogInputStream 源码

kafka CompressionRatioEstimator 源码

kafka CompressionType 源码

kafka ControlRecordUtils 源码

kafka ConvertedRecords 源码

kafka DefaultRecord 源码