Creation of nova::db::sync

In order to standardize the way dbsync are run across our modules,
we create a new class nova::db::sync.
This class will be included if sync_db is enabled.

By making this transition the nova::db::sync class
can be returned by the ENC.

A use case would be in an highly available environment, with 3 galera
nodes, include nova::api on every node with sync_db set to false
and have the ENC return nova::db::sync just for one node.

Change-Id: I795178f83fe5b997a2574fe17263643688efc48c

manifests/api.pp

@@ -346,14 +346,7 @@ class nova::api(
   # Added arg and if statement prevents this from being run
   # where db is not active i.e. the compute
   if $sync_db {
-    Package<| title == $::nova::params::api_package_name |>    ~> Exec['nova-db-sync']
+    include ::nova::db::sync
-    Package<| title == $::nova::params::common_package_name |> ~> Exec['nova-db-sync']
-
-    exec { 'nova-db-sync':
-      command     => '/usr/bin/nova-manage db sync',
-      refreshonly => true,
-      subscribe   => Exec['post-nova_config'],
-    }
   }
 
   # Remove auth configuration from api-paste.ini

manifests/db/sync.pp

@@ -0,0 +1,22 @@
+#
+# Class to execute nova dbsync
+#
+class nova::db::sync {
+
+  include ::nova::params
+
+  Package<| tag =='nova-package'  |> ~> Exec['nova-db-sync']
+  Exec['nova-db-sync'] ~> Service <| tag == 'nova-service' |>
+
+  Nova_config <||> -> Exec['nova-db-sync']
+  Nova_config <| title == 'database/connection' |> ~> Exec['nova-db-sync']
+
+  Exec<| title == 'post-nova_config' |> ~> Exec['nova-db-sync']
+
+  exec { 'nova-db-sync':
+    command     => '/usr/bin/nova-manage db sync',
+    refreshonly => true,
+    logoutput   => on_failure,
+  }
+
+}

spec/classes/nova_db_sync_spec.rb

@@ -0,0 +1,42 @@
+require 'spec_helper'
+
+describe 'nova::db::sync' do
+
+  shared_examples_for 'nova-dbsync' do
+
+    it 'runs nova-db-sync' do
+      is_expected.to contain_exec('nova-db-sync').with(
+        :command     => '/usr/bin/nova-manage db sync',
+        :refreshonly => 'true',
+        :logoutput   => 'on_failure'
+      )
+    end
+
+  end
+
+  context 'on a RedHat osfamily' do
+    let :facts do
+      {
+        :osfamily                 => 'RedHat',
+        :operatingsystemrelease   => '7.0',
+        :concat_basedir => '/var/lib/puppet/concat'
+      }
+    end
+
+    it_configures 'nova-dbsync'
+  end
+
+  context 'on a Debian osfamily' do
+    let :facts do
+      {
+        :operatingsystemrelease => '7.8',
+        :operatingsystem        => 'Debian',
+        :osfamily               => 'Debian',
+        :concat_basedir => '/var/lib/puppet/concat'
+      }
+    end
+
+    it_configures 'nova-dbsync'
+  end
+
+end