kafka SchemaSourceTask 源码

kafka SchemaSourceTask 代码

文件路径：/connect/runtime/src/main/java/org/apache/kafka/connect/tools/SchemaSourceTask.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.connect.tools;

import org.apache.kafka.connect.data.Schema;
import org.apache.kafka.connect.data.SchemaBuilder;
import org.apache.kafka.connect.data.Struct;
import org.apache.kafka.connect.errors.ConnectException;
import org.apache.kafka.connect.source.SourceRecord;
import org.apache.kafka.connect.source.SourceTask;
import org.apache.kafka.tools.ThroughputThrottler;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.Collections;
import java.util.List;
import java.util.Map;

public class SchemaSourceTask extends SourceTask {

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

    public static final String NAME_CONFIG = "name";
    public static final String ID_CONFIG = "id";
    public static final String TOPIC_CONFIG = "topic";
    public static final String NUM_MSGS_CONFIG = "num.messages";
    public static final String THROUGHPUT_CONFIG = "throughput";
    public static final String MULTIPLE_SCHEMA_CONFIG = "multiple.schema";
    public static final String PARTITION_COUNT_CONFIG = "partition.count";

    private static final String ID_FIELD = "id";
    private static final String SEQNO_FIELD = "seqno";
    private ThroughputThrottler throttler;

    private int id; // Task ID
    private String topic;
    private Map<String, Integer> partition;
    private long startingSeqno;
    private long seqno;
    private long count;
    private long maxNumMsgs;
    private boolean multipleSchema;
    private int partitionCount;

    private final static Schema VALUE_SCHEMA = SchemaBuilder.struct().version(1).name("record")
        .field("boolean", Schema.BOOLEAN_SCHEMA)
        .field("int", Schema.INT32_SCHEMA)
        .field("long", Schema.INT64_SCHEMA)
        .field("float", Schema.FLOAT32_SCHEMA)
        .field("double", Schema.FLOAT64_SCHEMA)
        .field("partitioning", Schema.INT32_SCHEMA)
        .field("id", Schema.INT32_SCHEMA)
        .field("seqno", Schema.INT64_SCHEMA)
        .build();

    private final static Schema VALUE_SCHEMA_2 = SchemaBuilder.struct().version(2).name("record")
        .field("boolean", Schema.BOOLEAN_SCHEMA)
        .field("int", Schema.INT32_SCHEMA)
        .field("long", Schema.INT64_SCHEMA)
        .field("float", Schema.FLOAT32_SCHEMA)
        .field("double", Schema.FLOAT64_SCHEMA)
        .field("partitioning", Schema.INT32_SCHEMA)
        .field("string", SchemaBuilder.string().defaultValue("abc").build())
        .field("id", Schema.INT32_SCHEMA)
        .field("seqno", Schema.INT64_SCHEMA)
        .build();

    @Override
    public String version() {
        return new SchemaSourceConnector().version();
    }

    @Override
    public void start(Map<String, String> props) {
        final long throughput;
        String name = props.get(NAME_CONFIG);
        try {
            id = Integer.parseInt(props.get(ID_CONFIG));
            topic = props.get(TOPIC_CONFIG);
            maxNumMsgs = Long.parseLong(props.get(NUM_MSGS_CONFIG));
            multipleSchema = Boolean.parseBoolean(props.get(MULTIPLE_SCHEMA_CONFIG));
            partitionCount = Integer.parseInt(props.getOrDefault(PARTITION_COUNT_CONFIG, "1"));
            throughput = Long.parseLong(props.get(THROUGHPUT_CONFIG));
        } catch (NumberFormatException e) {
            throw new ConnectException("Invalid SchemaSourceTask configuration", e);
        }

        throttler = new ThroughputThrottler(throughput, System.currentTimeMillis());
        partition = Collections.singletonMap(ID_FIELD, id);
        Map<String, Object> previousOffset = this.context.offsetStorageReader().offset(partition);
        if (previousOffset != null) {
            seqno = (Long) previousOffset.get(SEQNO_FIELD) + 1;
        } else {
            seqno = 0;
        }
        startingSeqno = seqno;
        count = 0;
        log.info("Started SchemaSourceTask {}-{} producing to topic {} resuming from seqno {}", name, id, topic, startingSeqno);
    }

    @Override
    public List<SourceRecord> poll() {
        if (count < maxNumMsgs) {
            long sendStartMs = System.currentTimeMillis();
            if (throttler.shouldThrottle(seqno - startingSeqno, sendStartMs)) {
                throttler.throttle();
            }

            Map<String, Long> ccOffset = Collections.singletonMap(SEQNO_FIELD, seqno);
            int partitionVal = (int) (seqno % partitionCount);
            final Struct data;
            final SourceRecord srcRecord;
            if (!multipleSchema || count % 2 == 0) {
                data = new Struct(VALUE_SCHEMA)
                    .put("boolean", true)
                    .put("int", 12)
                    .put("long", 12L)
                    .put("float", 12.2f)
                    .put("double", 12.2)
                    .put("partitioning", partitionVal)
                    .put("id", id)
                    .put("seqno", seqno);

                srcRecord = new SourceRecord(partition, ccOffset, topic, id, Schema.STRING_SCHEMA, "key", VALUE_SCHEMA, data);
            } else {
                data = new Struct(VALUE_SCHEMA_2)
                    .put("boolean", true)
                    .put("int", 12)
                    .put("long", 12L)
                    .put("float", 12.2f)
                    .put("double", 12.2)
                    .put("partitioning", partitionVal)
                    .put("string", "def")
                    .put("id", id)
                    .put("seqno", seqno);

                srcRecord = new SourceRecord(partition, ccOffset, topic, id, Schema.STRING_SCHEMA, "key", VALUE_SCHEMA_2, data);
            }

            System.out.println("{\"task\": " + id + ", \"seqno\": " + seqno + "}");
            seqno++;
            count++;
            return Collections.singletonList(srcRecord);
        } else {
            throttler.throttle();
            return Collections.emptyList();
        }
    }

    @Override
    public void stop() {
        throttler.wakeup();
    }
}

相关信息

kafka 源码目录

相关文章

kafka MockConnector 源码

kafka MockSinkConnector 源码

kafka MockSinkTask 源码

kafka MockSourceConnector 源码

kafka MockSourceTask 源码

kafka PredicateDoc 源码

kafka SchemaSourceConnector 源码

kafka TransformationDoc 源码

kafka VerifiableSinkConnector 源码

kafka VerifiableSinkTask 源码