What this PR does / why we need it:
set REST resources as singleton, reusing recources for better perf/stability
Which issue(s) this PR fixes(optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #
What this PR does / why we need it: set REST resources as singleton, reusing recources for better perf/stability Which issue(s) this PR fixes (optional, in
fixes #<issue number>(, fixes #<issue_number>, ...)format, will close the issue(s) when PR gets merged): Fixes #Special notes for your reviewer: