Re: [PATCH] COPY .. COMPRESSED

On Tue, Jan 15, 2013 at 03:37:07PM -0500, Christopher Browne wrote:
> On Tue, Jan 15, 2013 at 2:53 PM, Stephen Frost <sfrost@snowman.net> wrote:
> > The popen patch doesn't support the '|compression-binary' option through
> > the FE protocol.  Even if it did, it would only be available for
> > superusers as we can't allow regular users to run arbitrary commands on
> > the server-side.
> 
> That points towards a fix that involves having a set of non-arbitrary commands
> that we allow plain users to use.
> 
> Hmm.  There's an interesting thought...
> 
> How about having a "pg_filters" table in pg_catalog which allows capturing
> labels and names of known-to-be-safe binary filters:
> 
> insert into pg_filters (label, location)
> values
> ('zcat', '/usr/bin/zcat'),
> ('bzip2', '/usr/bin/bzip2'),
> ('bunzip2', '/usr/bin/bunzip2');
> 
> And then having some capability to grant permissions to roles to use
> these filters.
> 
> That's not a "version 1" capability...  Suppose we have, in 9.3, that there are
> direct references to "|/usr/bin/zcat" (and such), and then hope, in
> 9.4, to tease
> this out to be a non-superuser-capable facility via the above pg_filters?
> 
> These filters should be useful for FDWs as well as for COPY.

Well, COPY is super-user only, so it seems only useful for FDW, no?  We
already have lots of user-configuration FDW commands, so I can see
adding this one too.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
 + It's impossible for everything to be true. +