In short, the problem is that older Postgres versions store passwords
hashed as md5. When you dump such a database, the dump naturally also
contains md5-hashed passwords.
Restoring from that dump used to create users and updates their passwords
with these md5 hashes.
However, Postgres v14 prefers does not like md5-hashed passwords now (by default),
which breaks connectivity. Postgres v14 prefers `scram-sha-256` for
authentication.
Our solution is to just ignore setting passwords (`ALTER ROLE ..`
statements) when restoring dumps. We don't need to set passwords as
defined in the dump anyway, because the playbook creates users
and manages their passwords by itself.
Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/1340
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.
We were running into conflicts, because having initialized
the roles (users) and databases, trying to import leads to
errors (role XXX already exists, etc.).
We were previously ignoring the Synapse database (`homeserver`)
when upgrading/importing, because that one gets created by default
whenever the container starts.
For our additional databases, it's a similar situation now.
It's not created by default as soon as Postgres starts with an empty
database, but rather we create it as part of running the playbook.
So we either need to skip those role/database creation statements
while upgrading/importing, or to avoid creating the additional database
and rely on the import for that. I've gone for the former, because
it's already similar to what we were doing and it's simpler
(it lets `setup_postgres.yml` be the same in all scenarios).
We do use some `:latest` images by default for the following services:
- matrix-dimension
- Goofys (in the matrix-synapse role)
- matrix-bridge-appservice-irc
- matrix-bridge-appservice-discord
- matrix-bridge-mautrix-facebook
- matrix-bridge-mautrix-whatsapp
It's terribly unfortunate that those software projects don't release
anything other than `:latest`, but that's how it is for now.
Updating that software requires that users manually do `docker pull`
on the server. The playbook didn't force-repull images that it already
had.
With this patch, it starts doing so. Any image tagged `:latest` will be
force re-pulled by the playbook every time it's executed.
It should be noted that even though we ask the `docker_image` module to
force-pull, it only reports "changed" when it actually pulls something
new. This is nice, because it lets people know exactly when something
gets updated, as opposed to giving the indication that it's always
updating the images (even though it isn't).
Previously, it only mentioned exposing for psql-usage purposes.
Realistically, it can be used for much more. Especially given that
psql can be easily accessed via our matrix-postgres-cli script,
without exposing the container port.
