Someone

    configfile { '/etc/nagios/':
        source => 'system/nagios/',
        owner => nagios,
        group => nagios,
        recurse => true,
        require => Package['nagios.x86_64'],
        notify => Service['nagios'],
    }

    service { nagios:
        ensure => running,
        require => Package['nagios.x86_64'],
        enable => true,
        restart => "/etc/init.d/nagios reload"
    }

#### elsewhere
define configfile($owner = root, $group = root, $mode = 644, $source,
          $backup = main, $recurse = false, $ensure = file) {
    file { $name:
        mode => $mode,
        owner => $owner,
        group => $group,
        backup => $backup,
        recurse => $recurse,
        ensure => $ensure,
        source => "puppet:///config/$source"
    }
}