Prometheus daemon is not restarting when command-line arguments are changed

[sharadgaur]

Adding or removing any command-line argument to Prometheus class does not trigger daemon restart.

class { 'prometheus':
    configname               => 'prometheus.yml',
    localstorage             => $storage_path,
    manage_user              => false,
    manage_group             => false,
    external_url             => "https://prometheus.test.fake.dns.org",
...
  }

In this case, external_url is a command-line argument to Prometheus

[alexjfisher]

I think this is only an issue with systemd.

puppet-prometheus/manifests/config.pp

Lines 160 to 162 in 0c5e1a1

	File {
	notify => Class['prometheus::run_service'],
	}

should be defaulting the notify parameter of all file resources in config.pp
The idea is that some file resources can then notify prometheus::service_reload instead.

Using resource defaults like this is not recommended. 'Area of effect' can be confusing and cause unintentional results. See https://puppet.com/docs/puppet/5.5/lang_defaults.html#behavior

As for systemd...

puppet-prometheus/manifests/config.pp

Line 163 in 0c5e1a1

$systemd_notify = [Exec['prometheus-systemd-reload'], Class['prometheus::run_service']]

hasn't done anything for about 2 years. The variable is not used and the Exec referenced doesn't exist either.

[sharadgaur]

Should I remove the

File { 
   notify => Class['prometheus::run_service'], 
 } 

from config.pp and make systemd config to use $systemd_notify variable? I really don't want to use Exec.
If you don't mind we can get rid of $system_notify