Status
Current state: Adopted
Discussion thread: here
JIRA: KAFKA-8455
Motivation
Often, when reading an input topic, the key is expected to be null, but there's actually no way to represent this fact in Consumed, leading to confusing type signatures down the topology. For example, you might use the BytesSerde, but then you have a KStream<Bytes,...>. When maintaining a large application, this becomes a hazard, since you'd need to "be really careful" not to try and dereference the key at any point, since you actually know it's always null. One might use the BytesSerde, but then you have a KStream<Bytes,...>. When maintaining a large application, this becomes a hazard, since you'd need to "be really careful" not to try and dereference the key at any point, since you actually know it's always null.
Public Interfaces
I propose to add the following new SerDe:
static public final class VoidSerde extends WrapperSerde<Void> { } public class VoidSerializer implements Serializer<Void> { } public class VoidDeserializer implements Deserializer<Void> { }
If not null parameters passed then an java.lang.IllegalArgumentException
will be thrown.
Proposed Changes
I want to add VoidSerde
to Serdes
class.
Compatibility, Deprecation, and Migration Plan
There are no compatibility issues here.
Rejected Alternatives
NullSerdes
, NothingSerdes
naming was rejected during KIP discussion.