Batch tracking is OK.
Event tracking is OK if consumer does not use retry queue.
is_batch_done(consumer, batch)
returns:
true - batch is done already false - batch is not done yet
set_batch_done(consumer, batch)
returns:
true - tagging successful, batch was not done yet false - batch was done already
is_batch_done(consumer, batch, event)
returns:
true - event is done false - event is not done yet
set_batch_done(consumer, batch, event)
returns:
true - tagging was successful, event was not done false - event is done already