Re: Review of pg_archivecleanup -x option patch

On 02/01/2012 07:53 AM, Alex Shulgin wrote:
> One problem I've found while trying the example workflow is this:
>
> ~/local/postgresql/HEAD$ ./bin/pg_archivecleanup -d -x .gz data/archive/ 000000010000000000000002.00000020.backup.gz
> pg_archivecleanup: invalid filename input
> Try "pg_archivecleanup --help" for more information.
>
> I think we could accept the suffixed WAL filename and strip the suffix;
> another idea is to actually detect the suffix (if any) from the last
> command line argument, thus rendering the -x option unnecessary.

Going full-on automatic with detecting the suffix seems like it might do 
the wrong thing when presented with a strange extension.  I know a lot 
of the time I use pg_archivecleanup is inside scripts that tend to get 
setup and then ignored.  If one of those has a bug, or unexpected data 
appears in the archive, I'd rather see this sort of major, obvious 
failure--not an attempt to sort things out that might make a bad decision.

The smaller step of automatically stripping the specified suffix from 
the input file name, when it matches the one we've told the program to 
expect, seems like a usability improvement unlikely to lead to bad 
things though.  I've certainly made the mistake you've shown when using 
the patched version of the program myself, just didn't think about 
catching and correcting it myself before.  We can rev this to add that 
feature and resubmit easily enough, will turn that around soon.

-- 
Greg Smith   2ndQuadrant US    greg@2ndQuadrant.com   Baltimore, MD
PostgreSQL Training, Services, and 24x7 Support www.2ndQuadrant.com