Factory class for Flink's KeyedSerializationSchema. It is extracted for purpose when for creation
of KafkaSerializationSchema are needed additional avro related information. SerializationSchema will take
KafkaSerializationSchema with key extracted in the step before serialization
Factory class for Flink's KeyedSerializationSchema. It is extracted for purpose when for creation of KafkaSerializationSchema are needed additional avro related information. SerializationSchema will take KafkaSerializationSchema with key extracted in the step before serialization