Warning about invalid .pgpass passwords

Bruce Momjian wrote:
> Tom Lane wrote:
> > Alvaro Herrera <alvherre@commandprompt.com> writes:
> > > It had to do with me having a bogus password in .pgpass (so psql was
> > > first trying empty password, then the one in .pgpass, and both failing).
> > > Pilot error.  However, I'd say that we ought to give a notice if the
> > > password in .pgpass fails.
> > 
> > Can we do something like
> > 	ERROR: password authentication failed (using password from .pgpass)
> > ie, just tack on a comment to the error message?
> 
> I looked into that but found it difficult to implement because only
> libpq knows about pgpass, while the message is printed by psql.

I just got confused for +10 minutes by an incorrect .pgpass password, so
I found new interest in improving this reported behavior.  ;-)

The attached patch reports the fact that .pgpass was used if the libpq
connection fails:

	$ psql -h localhost test
	psql: FATAL:  password authentication failed for user "postgres"
	(password retrieved from .pgpass)

I am not sure if I like the parentheses or not.  Ideally I would report
this only for password failures but that information is not passed back
from the server except as an error string.

I am thinking this could be in 9.0.

-- 
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  PG East:  http://www.enterprisedb.com/community/nav-pg-east-2010.do