Re: POLA violation with \c service= - Mailing list pgsql-hackers

On Wed, Dec 17, 2014 at 08:14:04AM -0500, Andrew Dunstan wrote:

>
> On 12/17/2014 04:11 AM, Heikki Linnakangas wrote:
> >On 12/17/2014 10:03 AM, Albe Laurenz wrote:
> >>David Fetter wrote:
> >>>I've noticed that psql's  \c function handles service= requests in a
> >>>way that I can only characterize as broken.
> >>>
> >>>This came up in the context of connecting to a cloud hosting service
> >>>named after warriors or a river or something, whose default hostnames
> >>>are long, confusing, and easy to typo, so I suspect that service= may
> >>>come up more often going forward than it has until now.
> >>>
> >>>For example, when I try to use
> >>>
> >>>\c "service=foo"
> >>>
> >>>It will correctly figure out which database I'm trying to connect to,
> >>>but fail to notice that it's on a different host, port, etc., and
> >>>hence fail to connect with a somewhat unhelpful error message.
> >>>
> >>>I can think of a few approaches for fixing this:
> >>>
> >>>0.  Leave it broken.
> >>>1.  Disable "service=" requests entirely in \c context, and error out
> >>>if attempted.
> >>>2.  Ensure that \c actually uses all of the available information.
> >>>
> >>>Is there another one I missed?
> >>>
> >>>If not, which of the approaches seems reasonable?
> >>
> >>#2 is the correct solution, #1 a band aid.
> >
> >It would be handy, if \c "service=foo" actually worked. We should do #3.
> >If the database name is actually a connection string, or a service
> >specification, it should not re-use the hostname and port from previous
> >connection, but use the values from the connection string or service file.
>
>
> Yeah, that's the correct solution. It should not be terribly difficult to
> create a test for a conninfo string in the dbname parameter. That's what
> libpq does after all. We certainly don't want psql to have to try to
> interpret the service file. psql just needs to let libpq do its work in this
> situation.

letting libpq handle this is the only sane plan for fixing it.  I'm
looking into that today.