The postgresql module has a postStart section that waits for a database
to accept connections before continuing. However, this assumes various
properties about the database - specifically the database user
and (implicitly) the database name. This means that for old
installations, this command fails because there is no 'postgres' user,
and the service never starts.
While 7deff39 does create the 'postgres' user, a better solution is to
use `pg_isready`, who's sole purpose is to check if the database is
accepting connections. This has no dependency on users, so should be
more robust.
Old PostgreSQL installations were created using the 'root' database
user. In this case, we need to create a new 'postgres' account, as we
now assume that this is the superuser account.
Unfortunately, these machines will be left with a 'root' user as
well (which will have ownership of some databases). While PostgreSQL
does let you rename superuser accounts, you can only do that when you
are connected as a *different* database user. Thus we'd have to create a
special superuser account to do the renaming. As we default to using
ident authentication, we would have to create a system level user to do
this. This all feels rather complex, so I'm currently opting to keep the
'root' user on these old machines.
This allows to define systemd.path(5) units, for example like this:
{
systemd = let
description = "Set Key Permissions for xyz.key";
in {
paths.set-key-perms = {
inherit description;
before = [ "network.target" ];
wantedBy = [ "multi-user.target" ];
pathConfig.PathChanged = "/run/keys/xyz.key";
};
services.set-key-perms = {
inherit description;
serviceConfig.Type = "oneshot";
script = "chown myspecialkeyuser /run/keys/xyz.key";
};
};
}
The example here is actually useful in order to set permissions for the
NixOps keys target to ensure those permisisons aren't reset whenever the
key file is reuploaded.
Signed-off-by: aszlig <aszlig@redmoonstudios.org>
as per postgresql manual, interactions with psql should be carried
out with the postgresql system user and postgresql db user by default.
ensure it happens in postStart.
This reverts commit f7d5e83abb. It
breaks the Firefox and Xfce tests:
in job ‘tests.firefox.x86_64-linux’:
cannot coerce a boolean to a string
in job ‘tests.xfce.x86_64-linux’:
infinite recursion encountered
