test: postgres storage privs

Author: soedirgo

nix/tests/sql/storage.sql

@@ -95,3 +95,21 @@ order by
 
 -- storage service migrations
 select * from storage.migrations ;
+
+-- postgres can grant storage privileges to custom roles
+create role r;
+grant r to postgres;
+
+set role r;
+select * from storage.buckets;
+
+set role postgres;
+grant usage on schema storage to r;
+grant select on storage.buckets to r;
+
+set role r;
+select * from storage.buckets;
+
+reset role;
+drop owned by r;
+drop role r;