Page History

...

When the group is Stable (i.e. when there are active consumers in the group), the above command returns the associated topic partition assignment for each member of the group, and that assignment can be used to extract the corresponding committed offset(s). However, if the group state is Empty (i.e. when there are no active consumers in the group) there is no associated topic partition info in {{DescribeGroups Response}}. Therefore, DescribeGroups Response in its current protocol would not help.

...

The second suggestion has to do with how the above API is accessed and called. Currently, the way the offset information for each topic partition in a Stable group is returned is through creating a "dummy" consumer in the group and use its {{committed}} interface  interface to extract those offset information:

...

1. Changing the DescribeGroups protocol so it also returns the offset information for all topic partitions from which the group has consumed from since its creation. More detailed can be found here.
2. Exposing the added OffsetFetch behavior through a new interface in {{KafkaConsumer}}, which would still imply that the dummy consumer has to be created in the group in order to retrieve offsets.  More details can be found here.