Resource Type: systemd units

[fornellas]

For good or bad... systemd is the de facto standard in Linux to manage services. Let's add support to it.

Some considerations:

• We must manage unit definitions and on changes, call systemctl daemon-reload and systemctl reload-or-restart $unit.
• We may either create a new resource type SystemdUnit or integrate with File to implement that.
• We should integrate with APTPackage, to detect changes to any package configuration files, and identify if the package contains any systemd units, and then systemctl reload-or-restart $unit on changes.

References:

• https://www.freedesktop.org/software/systemd/man/systemd.unit.html
• https://www.freedesktop.org/software/systemd/man/org.freedesktop.systemd1.html#
• https://docs.chef.io/resources/systemd_unit/
• https://github.com/chef/chef/blob/main/lib/chef/provider/systemd_unit.rb#L224
• https://docs.ansible.com/ansible/latest/collections/ansible/builtin/systemd_module.html
• https://github.com/ansible/ansible/blob/devel/lib/ansible/modules/systemd_service.py

[gfechio]

Systemd would most likely needs not only the refresh but also if you to have it enabled on boot or not, the (in)famous systemctl enable service-name. Reload should check if unit exists or not and act on it.