apurtell commented on a change in pull request #390: HBASE-22623 - Add RegionObserver coprocessor hook for preWALAppend URL: https://github.com/apache/hbase/pull/390#discussion_r312194374
########## File path: hbase-server/src/main/java/org/apache/hadoop/hbase/coprocessor/RegionObserver.java ########## @@ -1104,4 +1104,16 @@ default DeleteTracker postInstantiateDeleteTracker( throws IOException { return delTracker; } + + /** + * Called just before the WAL Entry is appended to the WAL. Implementing this hook allows + * coprocessors to add extended attributes to the WALKey that then get persisted to the + * WAL, and are available to replication endpoints to use in processing WAL Entries. + * @param ctx the environment provided by the region server + * @param key the WALKey associated with a particular append to a WAL + */ + default void preWALAppend(ObserverContext<RegionCoprocessorEnvironment> ctx, WALKey key, Review comment: I also agree the "policy", such as it is, is contradictory and confusing. We need to attack the bigger picture on dev@ in a discussion about the future of coprocessors and our tolerance (or not) to the requests of the Phoenix project. The opinions are not monolithic. There are some supporters, there are some hostile positions, both are valid in my view, we need to sort out the disagreement. This issue isn't the right scope for that. The contradictory positions are evident in the tug and pull of the suggestions to the contributor. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services