`matrix_container_global_registry_prefix_override` may look similar to
the old `matrix_container_global_registry_prefix` variable
(removed in d6bf789710), but it's different.
The old `matrix_container_global_registry_prefix` variable was just a hardcode of `docker.io/` and roles that
needed to refer to `docker.io/` could use it. However, this was:
- not used by all roles, because some need another registry (not `docker.io/`)
- used only by roles within the playbook (`roles/custom`), not external roles
Overriding the old `matrix_container_global_registry_prefix` variable was rather pointless,
as it didn't cover everything.
The new `matrix_container_global_registry_prefix_override` variable, on the other hand,
lets you override the registry prefix for all components, regardless of whether they
use `docker.io/` or another registry by default.
This is useful to people who have somehow mirrored all container images to their own registry,
as it provides them with a single variable they can flip to influence the whole playbook.
This:
- brings consistency - no more mixing `_name_prefix` and `_registry_prefix`
- adds extensibility - a future patch will allow reconfiguring all registry prefixes for all roles in the playbook
We still have `_docker_` vs `_container_` inconsistencies.
These may be worked on later.
- forego removing Docker images - it's not effective anyway, because it
only removes the last version.. which is a drop in the bucket, usually
- do not reload systemd - it's none of our business. `--tags=start`,
etc., handle this
- combine all uninstall tasks under a single block, which only runs if
we detect traces (a leftover systemd .service file) of the component.
If no such .service is detected, we skip them all. This may lead to
incorect cleanup in rare cases, but is good enough for the most part.
This was useful when the order of these roles in relation to Synapse
mattered (when we were injecting stuff into Synapse variables during
runtime). This is no longer the case since 0ea7cb5d18, so all of
this can be removed.
These `init.yml` (now `inject_into_nginx_proxy.yml`) tasks do not need
to `always` run. They only need to run for `setup-all` and
`setup-nginx-proxy`. Unless we're dealing with these 2 tags, we can
spare ourselves a lot of work.
This patch also moves the `when` statement from `init.yml` into
`main.yml` in an effort to further optimize things by potentially
avoiding the extra file include.
