Kafka Connect SMT ApplyWithSchema requires struct error

问题

I have deployed a sample from confluent https://github.com/confluentinc/kafka-connect-insert-uuid for adding simple UUID field but I am getting an error that it requires struct. I am applying this within Debezium MySQLConnector

  Only Struct objects supported for [adding UUID to record], found: 
  java.lang.String\n\tat org.apache.kafka.connect.transforms.util.Requirements.requireStruct(Requirements.java:52)

What is a minimalist applyWithSchema method that just returns the record as is? I am trying to debug and need a HelloWorld SMT without any errors that have to apply methods including applyWithSchema

I think this is probably most simple for the application but need for applyWithSchema

Override
public R apply(R record) {
    
    return record.newRecord(
            record.topic(), record.kafkaPartition(),
            record.keySchema(), record.key(),
            record.valueSchema(), record.value(),
            record.timestamp()
    );
}

Override
public R applyWithSchema(R record) {
    // what is minimal transform here??
}

I just need these functions to run without error now, as I am making a change to record.headers().add() only.

Here is the applyWithSchema method that gives the error:

private R applyWithSchema(R record) {
    // FAILS HERE!
    final Struct value = requireStruct(operatingValue(record), PURPOSE);

    Schema updatedSchema = schemaUpdateCache.get(value.schema());
    if(updatedSchema == null) {
        updatedSchema = makeUpdatedSchema(value.schema()); 

        final Struct updatedValue = new Struct(updatedSchema);

        for (Field field : value.schema().fields()) {
         // updatedValue.put(field.name(), value.get(field));
        }

        //updatedValue.put(fieldName, getRandomUuid());

        return newRecord(record, updatedSchema, updatedValue);
    }

来源：https://stackoverflow.com/questions/63311462/kafka-connect-smt-applywithschema-requires-struct-error