If we load it at runtime, during matrix-synapse role execution,
it's good enough for matrix-synapse and all roles after that,
but.. it breaks when someone uses `--tags=setup-nginx-proxy` alone.
The downside of including this vars file like this in `setup.yml`
is that the variables contained in it cannot be overriden by the user
(in their inventory's `vars.yml`).
... but it's not like overriding these variables was possible anyway
when including them at runtime.
Some people run Coturn or Jitsi, etc., by themselves and disable it
in the playbook.
Because the playbook is trying to be nice and clean up after itself,
it was deleting these Docker images.
However, people wish to pull and use them separately and would rather
they don't get deleted.
We could make this configurable for the sake of this special case, but
it's simpler to just avoid deleting these images.
It's not like this "cleaning things up" thing works anyway.
As time goes on, the playbook gets updated with newer image tags
and we leave so many images behind. If one doesn't run
`docker system prune -a` manually once in a while, they'd get swamped
with images anyway. Whether we leave a few images behind due to the lack
of this cleanup now is pretty much irrelevant.
We log everything in systemd/journald for every service already,
so there's no need for double-logging, bridges rotating log files
manually and other such nonsense.
In short, this makes Synapse a 2nd class citizen,
preparing for a future where it's just one-of-many homeserver software
options.
We also no longer have a default Postgres superuser password,
which improves security.
The changelog explains more as to why this was done
and how to proceed from here.
I had intentionally held it back in 39ea3496a4
until:
- it received more testing (there were a few bugs during the
migration, but now it seems OK)
- this migration guide was written