pt-show-grants doesn't sort column-level privileges

[Peter Dolberg]

complete command run: ./pt-show-grants h=127.0.0.2,u=root --only myuser
pt-show-grants version: 2.2.16
MySQL version of server : MySQL 5.6.17, MySQL 5.6.19a, AWS Aurora 5.6.10a

Summary:
The pt-show-grants tool is supposed to canonicalize grants. Unfortunately, it doesn't do that for GRANT entries containing column-level privileges.

I ran the output of pt-show-grants against two databases, one MySQL 5.6.19 and the other AWS Aurora 5.6.10a. The output was only different in the way that the columns in column-level privileges were ordered. In each case, it was clear that the columns weren't sorted.

Root cause and fix:

After looking at pt-show-grants source code, I see that columns in column-level privileges are left in the order that SHOW GRANTS returns them.

To fix this issue, we can sort the column-level privileges. I added the code below in the split_grants function at the end of the if block that tests for column-level privileges.

      # sort columns in column-level permissions
      @grants = map {
        $_ =~ s/(INSERT|SELECT|UPDATE)\s\((.+?)\)/"$1 (" . join(', ',sort(split(', ',$2))) . ')'/me;
        $_;
      } @grants;

I've attached a patch with this code in it.

[Frank Cizmich (frank-cizmich)]

Fixed as suggested.
Modified test suite to accommodate for change.

[Shahriyar Rzayev (rzayev-sehriyar)]

Percona now uses JIRA for bug reports so this bug report is migrated to: https://jira.percona.com/browse/PT-697