io.confluent.kafkarest.v2.AvroKafkaConsumerState.java Source code

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Here is the source code for io.confluent.kafkarest.v2.AvroKafkaConsumerState.java

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/**
 * Copyright 2017 Confluent Inc.
 *
 * Licensed 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 io.confluent.kafkarest.v2;

import com.fasterxml.jackson.databind.JsonNode;
import io.confluent.kafkarest.ConsumerInstanceId;
import io.confluent.kafkarest.ConsumerRecordAndSize;
import io.confluent.kafkarest.KafkaRestConfig;
import io.confluent.kafkarest.converters.AvroConverter;
import io.confluent.kafkarest.entities.AvroConsumerRecord;
import kafka.serializer.Decoder;
import org.apache.kafka.clients.consumer.Consumer;
import org.apache.kafka.clients.consumer.ConsumerRecord;

import java.util.Properties;

/**
 * Avro implementation of KafkaConsumerState, which decodes into GenericRecords or primitive types.
 */
public class AvroKafkaConsumerState extends KafkaConsumerState<Object, Object, JsonNode, JsonNode> {

    // Note that this could be a static variable and shared, but that causes tests to break in
    // subtle ways because it causes state to be shared across tests, but only for the consumer.
    private Decoder<Object> decoder = null;

    public AvroKafkaConsumerState(KafkaRestConfig config, ConsumerInstanceId instanceId, Consumer consumer) {
        super(config, instanceId, consumer);
        Properties props = new Properties();
        props.setProperty("schema.registry.url", config.getString(KafkaRestConfig.SCHEMA_REGISTRY_URL_CONFIG));
    }

    @Override
    protected Decoder<Object> getKeyDecoder() {
        return decoder;
    }

    @Override
    protected Decoder<Object> getValueDecoder() {
        return decoder;
    }

    @Override
    public ConsumerRecordAndSize<JsonNode, JsonNode> createConsumerRecord(ConsumerRecord<Object, Object> record) {
        AvroConverter.JsonNodeAndSize keyNode = AvroConverter.toJson(record.key());
        AvroConverter.JsonNodeAndSize valueNode = AvroConverter.toJson(record.value());
        return new ConsumerRecordAndSize<JsonNode, JsonNode>(new AvroConsumerRecord(record.topic(), keyNode.json,
                valueNode.json, record.partition(), record.offset()), keyNode.size + valueNode.size);
    }
}