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.kafka.streams.processor.internals;
  
  import org.apache.kafka.common.config.ConfigException;
  import org.apache.kafka.common.header.Headers;
  import org.apache.kafka.common.metrics.Sensor;
  import org.apache.kafka.common.serialization.Deserializer;
  import org.apache.kafka.streams.errors.StreamsException;
  import org.apache.kafka.streams.processor.TimestampExtractor;
  import org.apache.kafka.streams.processor.api.Record;
  import org.apache.kafka.streams.processor.internals.metrics.ProcessorNodeMetrics;
  
  import static org.apache.kafka.streams.kstream.internals.WrappingNullableUtils.prepareKeyDeserializer;
  import static org.apache.kafka.streams.kstream.internals.WrappingNullableUtils.prepareValueDeserializer;
  
  public class SourceNode<KIn, VIn> extends ProcessorNode<KIn, VIn, KIn, VIn> {
  
      private InternalProcessorContext<KIn, VIn> context;
      private Deserializer<KIn> keyDeserializer;
      private Deserializer<VIn> valDeserializer;
      private final TimestampExtractor timestampExtractor;
      private Sensor processAtSourceSensor;
  
      public SourceNode(final String name,
                        final TimestampExtractor timestampExtractor,
                        final Deserializer<KIn> keyDeserializer,
                        final Deserializer<VIn> valDeserializer) {
          super(name);
          this.timestampExtractor = timestampExtractor;
          this.keyDeserializer = keyDeserializer;
          this.valDeserializer = valDeserializer;
      }
  
      public SourceNode(final String name,
                        final Deserializer<KIn> keyDeserializer,
                        final Deserializer<VIn> valDeserializer) {
          this(name, null, keyDeserializer, valDeserializer);
      }
  
      KIn deserializeKey(final String topic, final Headers headers, final byte[] data) {
          return keyDeserializer.deserialize(topic, headers, data);
      }
  
      VIn deserializeValue(final String topic, final Headers headers, final byte[] data) {
          return valDeserializer.deserialize(topic, headers, data);
      }
  
      @Override
      public void init(final InternalProcessorContext<KIn, VIn> context) {
          // It is important to first create the sensor before calling init on the
          // parent object. Otherwise due to backwards compatibility an empty sensor
          // without parent is created with the same name.
          // Once the backwards compatibility is not needed anymore it might be possible to
          // change this.
          processAtSourceSensor = ProcessorNodeMetrics.processAtSourceSensor(
              Thread.currentThread().getName(),
              context.taskId().toString(),
              context.currentNode().name(),
              context.metrics()
          );
          super.init(context);
          this.context = context;
  
          try {
              keyDeserializer = prepareKeyDeserializer(keyDeserializer, context);
          } catch (final ConfigException | StreamsException e) {
              throw new StreamsException(String.format("Failed to initialize key serdes for source node %s", name()), e, context.taskId());
          }
  
          try {
              valDeserializer = prepareValueDeserializer(valDeserializer, context);
          } catch (final ConfigException | StreamsException e) {
              throw new StreamsException(String.format("Failed to initialize value serdes for source node %s", name()), e, context.taskId());
          }
      }
  
  
      @Override
      public void process(final Record<KIn, VIn> record) {
          context.forward(record);
          processAtSourceSensor.record(1.0d, context.currentSystemTimeMs());
      }
  
      /**
       * @return a string representation of this node, useful for debugging.
       */
      @Override
      public String toString() {
          return toString("");
      }
  
      public TimestampExtractor timestampExtractor() {
          return timestampExtractor;
      }
  }