apt::reboot_required_notify::jessie: manage APT pinning to fetch reboot-notifier from jessie-backports, when running on Jessie.

manifests/reboot_required_notify/jessie.pp

@@ -1,5 +1,15 @@
 class apt::reboot_required_notify::jessie ($ensure = present) {
 
+  $pinning_ensure = $::operatingsystemmajrelease ? {
+    8       => present,
+    default => absent,
+  }
+  apt::preferences_snippet { 'reboot-notifier':
+    ensure   => $pinning_ensure,
+    pin      => 'release o=Debian Backports,a=jessie-backports',
+    priority => 991,
+  }
+
   # On Jessie and newer, this package installs the script that created
   # /var/run/reboot-required*.
   # This script (/usr/share/update-notifier/notify-reboot-required) is
@@ -7,7 +17,8 @@ class apt::reboot_required_notify::jessie ($ensure = present) {
   # This package also sends a daily email to the administrator when a system
   # reboot is required, e.g. due to a kernel update.
   package { 'reboot-notifier':
-    ensure => $ensure,
+    ensure  => $ensure,
+    require => Apt::Preferences_snippet['reboot-notifier'],
   }
-  
+
 }