[HBASE-20567] Pass both old and new descriptors to pre/post hooks of modify operations for table and namespace

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0.0-alpha-1, 2.1.0, 2.0.1
• Assignee: Apekshit Sharma
• Reporter: Apekshit Sharma
• Created: 11/May/18 03:28
• Updated: 17/May/18 12:17
• Resolved: 16/May/18 19:04

Description

In postModify* hooks like postModifyX(..., Descriptor newDesc), there's no way of getting the old descriptor which was there before modification happened.
Having both old and new descriptors will make the hooks more useful.
We felt the need when we wanted to audit certain events but there was no way of deducing them by just seeing 'after-state' of modification.

To keep the method signatures consistent, i have modified both pre and post hooks with new arguments which are well named and commented.

Issue Links

• is required by: HBASE-20594 provide utility to compare old and new descriptors
• links to: Review Board (master)