We don't really need to fail in such a spectactular way,
but it's probably good to do. It will only happen for people
who are defining their own user/group id, which is rare.
It seems like a good idea to tell them that this doesn't work
as they expect anymore and to ask them to remove these variables,
which otherwise give them a fake sense of hope.
Related to #486 (Github Pull Request).
If one runs the playbook with `--tags=setup-all`, it would have been
fine.
But running with a specific tag (e.g. `--tags=setup-riot-web`) would
have made that initialization be skipped, and the `matrix-riot-web` role
would fail, due to missing variables.
With most people on Synapse v0.99+ and Synapse v1.0 now available,
we should no longer try to be backward compatible with Synapse 0.34,
because this just complicates the instructions for no good reason.
In most cases, there's not really a need to touch the system
firewall, as Docker manages iptables by itself
(see https://docs.docker.com/network/iptables/).
All ports exposed by Docker containers are automatically whitelisted
in iptables and wired to the correct container.
This made installing firewalld and whitelisting ports pointless,
as far as this playbook's services are concerned.
People that wish to install firewalld (for other reasons), can do so
manually from now on.
This is inspired by and fixes#97 (Github Issue).
Fixes#129 (Github Issue).
Unfortunately, we rely on `service_facts`, which is only available
in Ansible >= 2.5.
There's little reason to stick to an old version such as Ansible 2.4:
- some time has passed since we've raised version requirements - it's
time to move into the future (a little bit)
- we've recently (in 82b4640072) improved the way one can run
Ansible in a Docker container
From now on, Ansible >= 2.5 is required.
People who wish to rely on SRV records can prevent
the `/.well-known/matrix/server` file from being generated
(and thus, served.. which causes trouble).
This is a known/intentional regression since f92c4d5a27.
The new stance on this is that most people would not have
dnspython, but may have the `dig` tool. There's no good
reason for not increasing our chances of success by trying both
methods (Ansible dig lookup and using the `dig` CLI tool).
Fixes#85 (Github issue).
