content: /*
   * 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.beam.sdk.extensions.sql.meta.provider.kafka;
  
  import java.util.List;
  import org.apache.beam.sdk.io.kafka.KafkaRecord;
  import org.apache.beam.sdk.io.kafka.TimestampPolicyFactory;
  import org.apache.beam.sdk.schemas.Schema;
  import org.apache.beam.sdk.schemas.io.payloads.PayloadSerializer;
  import org.apache.beam.sdk.transforms.MapElements;
  import org.apache.beam.sdk.transforms.PTransform;
  import org.apache.beam.sdk.values.PCollection;
  import org.apache.beam.sdk.values.Row;
  import org.apache.beam.sdk.values.TypeDescriptor;
  import org.apache.beam.vendor.guava.v32_1_2_jre.com.google.common.collect.Iterables;
  import org.apache.kafka.clients.producer.ProducerRecord;
  
  public class PayloadSerializerKafkaTable extends BeamKafkaTable {
    private final PayloadSerializer serializer;
  
    PayloadSerializerKafkaTable(
        Schema requiredSchema,
        String bootstrapServers,
        List<String> topics,
        PayloadSerializer serializer,
        TimestampPolicyFactory timestampPolicyFactory) {
      super(requiredSchema, bootstrapServers, topics, timestampPolicyFactory);
      this.serializer = serializer;
    }
  
    @Override
    protected PTransform<PCollection<KafkaRecord<byte[], byte[]>>, PCollection<Row>>
        getPTransformForInput() {
      return new PTransform<PCollection<KafkaRecord<byte[], byte[]>>, PCollection<Row>>(
          "deserialize-kafka-rows") {
        @Override
        public PCollection<Row> expand(PCollection<KafkaRecord<byte[], byte[]>> input) {
          return input
              .apply(
                  MapElements.into(TypeDescriptor.of(Row.class))
                      .via(record -> serializer.deserialize(record.getKV().getValue())))
              .setRowSchema(getSchema());
        }
      };
    }
  
    @Override
    protected PTransform<PCollection<Row>, PCollection<ProducerRecord<byte[], byte[]>>>
        getPTransformForOutput() {
      String topic = Iterables.getOnlyElement(getTopics());
      return new PTransform<PCollection<Row>, PCollection<ProducerRecord<byte[], byte[]>>>(
          "serialize-kafka-rows") {
        @Override
        public PCollection<ProducerRecord<byte[], byte[]>> expand(PCollection<Row> input) {
          return input.apply(
              MapElements.into(new TypeDescriptor<ProducerRecord<byte[], byte[]>>() {})
                  .via(row -> new ProducerRecord<>(topic, new byte[] {}, serializer.serialize(row))));
        }
      };
    }
  }
  