Conditionally fall back to redhat service provider

This commit partially reverts Change-Id:
  Ic06ffc377f8982337d977bebb96ef7f6196e5c22 and puts in place
  conditionals to work around an issue in Puppet 4.0 through 4.4
  installations where the systemd service provider does not function
  because of a bug managing statically enabled services[1].

  [1] https://tickets.puppetlabs.com/browse/PUP-5353

Closes-Bug: #1577827
Change-Id: If5ea135b294995634506b745f80442e34b101a59

manifests/compute/libvirt.pp

@@ -158,6 +158,8 @@ class nova::compute::libvirt (
       ensure   => running,
       enable   => true,
       name     => $::nova::params::messagebus_service_name,
+      provider => $::nova::params::special_service_provider,
+
     }
     Package['libvirt'] -> Service['messagebus'] -> Service['libvirt']
   }
@@ -199,6 +201,7 @@ class nova::compute::libvirt (
     ensure   => running,
     enable   => true,
     name     => $libvirt_service_name,
+    provider => $::nova::params::special_service_provider,
     require  => Package['libvirt'],
   }
 
@@ -207,6 +210,7 @@ class nova::compute::libvirt (
       ensure   => running,
       enable   => true,
       name     => $virtlock_service_name,
+      provider => $::nova::params::special_service_provider,
       require  => Package['libvirt']
     }
   }
@@ -216,6 +220,7 @@ class nova::compute::libvirt (
       ensure   => running,
       enable   => true,
       name     => $virtlog_service_name,
+      provider => $::nova::params::special_service_provider,
       require  => Package['libvirt']
     }
   }

manifests/params.pp

@@ -55,12 +55,19 @@ class nova::params {
         'RedHat', 'CentOS', 'Scientific', 'OracleLinux': {
           if (versioncmp($::operatingsystemmajrelease, '7') < 0) {
             $messagebus_service_name  = 'messagebus'
+            $special_service_provider = undef
           } else {
+            if (versioncmp($::puppetversion, '4.5') < 0) {
+              $special_service_provider = 'redhat'
+            } else {
+              $special_service_provider = undef
+            }
             $messagebus_service_name = 'dbus'
           }
         }
         default: {
-          # not packaged on Fedora
+          # not required on Fedora
+          $special_service_provider = undef
           $messagebus_service_name  = undef
         }
       }
@@ -108,6 +115,8 @@ class nova::params {
           $spicehtml5proxy_package_name    = 'nova-consoleproxy'
           $spicehtml5proxy_service_name    = 'nova-spicehtml5proxy'
           $vncproxy_package_name           = 'nova-consoleproxy'
+          # Use default provider on Debian
+          $special_service_provider        = undef
           $libvirt_service_name            = 'libvirtd'
           $virtlock_service_name           = undef
           $virtlog_service_name            = undef
@@ -116,6 +125,8 @@ class nova::params {
           $spicehtml5proxy_package_name    = 'nova-spiceproxy'
           $spicehtml5proxy_service_name    = 'nova-spiceproxy'
           $vncproxy_package_name           = 'nova-novncproxy'
+          # Use default provider on Debian
+          $special_service_provider        = undef
           $libvirt_service_name            = 'libvirt-bin'
           $virtlock_service_name           = 'virtlockd'
           $virtlog_service_name            = 'virtlogd'

releasenotes/notes/fallback_to_redhat_intelligently-d3a158ae263f6103.yaml

@@ -0,0 +1,3 @@
+---
+features:
+  - Fallback to deprecated "redhat" service provider in an intellegent way to get around https://tickets.puppetlabs.com/browse/PUP-5353 on Puppet versions from 4.0 through 4.4.

releasenotes/notes/stop_service_provider-557dea3058c3bcec.yaml

@@ -1,3 +0,0 @@
----
-features:
-  - Stop overriding service providers, and let Puppet finds which one is the best.