Package io.smallrye.reactive.messaging.kafka

Interface DeserializationFailureHandler<T>

Type Parameters:
T - the expected type
public interface DeserializationFailureHandler<T>
Bean invoked on Kafka deserialization to implement custom failure handling.

Implementors must use @Identifier to provide a name to the bean. This name is then referenced in the channel configuration: mp.messaging.incoming.my-channel.[key|value]-deserialization-failure-handler=name.

In case a Kafka Record's key or value cannot be deserialized, this bean can provide failure handling via Mutiny's Uni interface to retry or to provide a fallback value. null is an accepted fallback value. If this bean throws an exception, this is considered as a fatal failure and the application is reported unhealthy.

  • Field Details

    • DESERIALIZATION_FAILURE_REASON

      static final String DESERIALIZATION_FAILURE_REASON
      Header name for deserialization failure message.
      See Also:

    • DESERIALIZATION_FAILURE_CAUSE

      static final String DESERIALIZATION_FAILURE_CAUSE
      Header name for deserialization failure cause if any.
      See Also:

    • DESERIALIZATION_FAILURE_IS_KEY

      static final String DESERIALIZATION_FAILURE_IS_KEY
      Header name used when the deserialization failure happened on a key. The value is "true" in this case, absent otherwise.
      See Also:

    • DESERIALIZATION_FAILURE_TOPIC

      static final String DESERIALIZATION_FAILURE_TOPIC
      Header name for the topic of the incoming message when a deserialization failure happen.
      See Also:

    • DESERIALIZATION_FAILURE_DATA

      static final String DESERIALIZATION_FAILURE_DATA
      Header name passing the data that was not able to be deserialized.
      See Also:

    • DESERIALIZATION_FAILURE_DESERIALIZER

      static final String DESERIALIZATION_FAILURE_DESERIALIZER
      Header name passing the class name of the underlying deserializer.
      See Also:

    • TRUE_VALUE

      static final byte[] TRUE_VALUE

  • Method Details

    • handleDeserializationFailure

      default T handleDeserializationFailure(String topic, boolean isKey, String deserializer, byte[] data, Exception exception, org.apache.kafka.common.header.Headers headers)
      Handles a deserialization issue for a record's key or value.
      Parameters:
      topic - the topic
      isKey - whether the failure happened when deserializing a record's key.
      deserializer - the used deserializer
      data - the data that was not deserialized correctly
      exception - the exception
      headers - the record headers, extended with the failure reason, causes, and data. May also be null
      Returns:
      the fallback T

    • decorateDeserialization

      default T decorateDeserialization(io.smallrye.mutiny.Uni<T> deserialization, String topic, boolean isKey, String deserializer, byte[] data, org.apache.kafka.common.header.Headers headers)
      Decorate the given wrapped deserialization action to apply fault tolerance actions. The default implementation calls handleDeserializationFailure(java.lang.String, boolean, java.lang.String, byte[], java.lang.Exception, org.apache.kafka.common.header.Headers) for retro compatibility.
      Parameters:
      deserialization - the deserialization call wrapped in Uni
      topic - the topic
      isKey - whether the deserialization is for a record's key.
      deserializer - the used deserializer
      data - the data to deserialize
      headers - the record headers. May be null
      Returns:
      the recovered T

    • addFailureDetailsToHeaders

      static org.apache.kafka.common.header.Headers addFailureDetailsToHeaders(String deserializer, String topic, boolean isKey, org.apache.kafka.common.header.Headers headers, byte[] data, Throwable failure)
      Extend record headers to add deserialization failure reason to the incoming message headers
      Parameters:
      deserializer - deserializer class name
      topic - the topic
      isKey - whether the failure happened when deserializing a record's key.
      headers - the record headers
      data - the data that was not deserialized correctly
      failure - the deserilization failure
      Returns:
      headers