[GitHub] [hbase] sandeepvinayak commented on a change in pull request #837: HBASE-23309: Adding the flexibility to ChainWalEntryFilter to filter the whole entry if all cells get filtered

[GitBox <gi...@apache.org>]

sandeepvinayak commented on a change in pull request #837: HBASE-23309: Adding the flexibility to ChainWalEntryFilter to filter the whole entry if all cells get filtered
URL: https://github.com/apache/hbase/pull/837#discussion_r347715850
 
 

 ##########
 File path: hbase-server/src/main/java/org/apache/hadoop/hbase/replication/ChainWALEntryFilter.java
 ##########
 @@ -68,13 +82,17 @@ public void initCellFilters() {
 
   @Override
   public Entry filter(Entry entry) {
+
     for (WALEntryFilter filter : filters) {
       if (entry == null) {
         return null;
       }
       entry = filter.filter(entry);
     }
     filterCells(entry);
+    if (shouldFilterEmptyEntry() && entry != null && entry.getEdit().isEmpty()) {
 
 Review comment:
   @apurtell This is the flexility we want to provide to customer replication endpoint so that they every custom replication endpoint doesn't need to re-implement everything what `ChainWALEntryFilter` already does. 
   
   Here is the scenario we want to cover, let's take an example:
   ```java
   CustomWALFilter implements WALEntryFilter, WALCellFilter {
       @override 
        public void filter(Entry) {
       }
       @override 
       public void filterCell(Entry, Cell){
       }
   }
   ```
   Custom Replication endpoint set the filters by:
   ```java
   ChainWALEntryFilter(filters); \\ new CustomWALFilter() is part of filters
   ```
   if `filter` in the above `CustomWALFilter` returns Entry but filterCell filters all the cells, the `ChainWALEntryFilter` will not return null in current implementation. Since most of the `CustomWALFilter` uses `ChainWALEntryFilter`, isn't it better to provide this flexibility in ChainWALFilter itself? Sure, it's possible to all this logic in CustomWALFilter, but shouldn't we provide re-usability through ChainWALFilter and provides a flexibility through a config? Let me know your thoughts. 

----------------------------------------------------------------
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:
users@infra.apache.org


With regards,
Apache Git Services