[postgresql] using peer auth through unix socket

[zerc]

Hi, everyone!

It seems like currently this feature doesn't work or I can't understand how I can use it. Look:

• Strange call of pg.connect:

if host == 'localhost' and password == '':
    # Use ident method
    connection = pg.connect("user=%s dbname=%s" % (user, dbname))

So this string goes into the user kwarg:

def connect(
        user=None, host='localhost', unix_sock=None, port=5432, database=None,
        password=None, ssl=False, timeout=None, **kwargs):

Also according to pg8000 we need to provide a path to unix_sock instead of host:

:keyword unix_sock:
    The path to the UNIX socket to access the database through, for
    example, ``'/tmp/.s.PGSQL.5432'``.  One of either ``host`` or
    ``unix_sock`` must be provided.

And I can't find a way to do this through the agent.

So anyone knows how I can make peer connection with the agent or is it really not working now?

Thanks

[DylanFrese]

I would also like to be able to use a UNIX Socket to monitor a postgres instance, it would simplify authentication as I wouldn't have to put credentials in the DataDog configuration file (the DataDog configuration is managed by SaltStack, but the Postgres configuration is deployed from another project and differs between server environments). Ideally, postgres.yaml would be able to take a unix_sock field in place of host/port.

If nobody wants to pick this up, I'll try creating a PR in the next few days, I just imagine it'll take me longer than someone who's more familiar with the project/Python.