: What I'd like to do is send a notification to another system when a document : have been deleted from the index. : : I first thought of doing it from the processDelete method of an : UpdateRequestProcessor, but because of the possibility of a rollback, it is : not a good idea.
why not? ... you can batch up the list of documents in your processDelete method, blank it out in your processRollback method, and send it to the other system in your processCommit method. Alternately, I suppose in your UpdateProccessor.processCommit method you could get the IndexReader and then loop over every doc and check it with IndexReader.isDeleted() (that might be simpler, but i suspect it would be less efficient ... not sure) -Hoss
