...

• Binary log format

• The network protocol and api behavior

• Any class in the public packages under clientsConfiguration, especially client configuration

  • org/apache/kafka/common/serialization

  • org/apache/kafka/common

  • org/apache/kafka/common/errors

  • org/apache/kafka/clients/producer

  • org/apache/kafka/clients/consumer (eventually, once stable)

• Monitoring

• Command line tools and arguments

• Anything else that will likely break existing users in some way when they upgrade

API Changes

Admin

public interface Admin {
    . . .
    public ListConsumerGroupsOptionsListGroupsResult listGroups();
    public ListConsumerGroupsOptionsListGroupsResult ListGroups(ListGroupsOptions options);
}

ListGroupsOptions

public class ListGroupsOptions {
    public ListGroupsOptions inStates(Set<GroupState> states);
    public ListGroupsOptions inTypes(Set<GroupType> types);
}

ListGroupsResult

public class ListGroupsResult {
    public KafkaFuture<Collection<GroupListing>> all();
    public KafkaFuture<Collection<GroupListing>> valid();
    public KafkaFuture<Collection<GroupListing>> errors();    
}

...

public class GroupListing {
    public String groupId();
    public Optional<GroupState> state();
    public Optional<GroupType> type();
}

GroupType

public enum GroupType {
    CONSUMER("consumer"),
    GENERIC("generic");
}

...

ConsumerGroupHeartbeat API

Admin API changes

• ListConsumerGroupsOptions

Compatibility, Deprecation, and Migration Plan

...