diff --git a/spec/classes/aodh_api_spec.rb b/spec/classes/aodh_api_spec.rb
index dd320b4d..3567e000 100644
--- a/spec/classes/aodh_api_spec.rb
+++ b/spec/classes/aodh_api_spec.rb
@@ -119,89 +119,44 @@ describe 'aodh::api' do
 
       it_raises 'a Puppet::Error', /Invalid service_name/
     end
-  end
 
-  context 'on Debian platforms' do
-    let :facts do
-      @default_facts.merge({
-        :osfamily               => 'Debian',
-        :operatingsystem        => 'Debian',
-        :operatingsystemrelease => '8.0',
-        :concat_basedir         => '/var/lib/puppet/concat',
-        :fqdn                   => 'some.host.tld',
-        :processorcount         => 2,
-      })
-    end
-
-    let :platform_params do
-      { :api_package_name => 'aodh-api',
-        :api_service_name => 'aodh-api' }
-    end
-
-    it_configures 'aodh-api'
-  end
-
-  context 'on RedHat platforms' do
-    let :facts do
-      @default_facts.merge({
-        :osfamily               => 'RedHat',
-        :operatingsystem        => 'RedHat',
-        :operatingsystemrelease => '7.1',
-        :fqdn                   => 'some.host.tld',
-        :concat_basedir         => '/var/lib/puppet/concat',
-        :processorcount         => 2,
-      })
-    end
-
-    let :platform_params do
-      { :api_package_name => 'openstack-aodh-api',
-        :api_service_name => 'openstack-aodh-api' }
-    end
-
-    it_configures 'aodh-api'
-  end
-
-  describe 'with custom auth_uri' do
-    let :facts do
-      @default_facts.merge({ :osfamily => 'RedHat' })
-    end
-    before do
-      params.merge!({
-        :keystone_auth_uri => 'https://foo.bar:1234/',
-      })
-    end
-    it 'should configure custom auth_uri correctly' do
-      is_expected.to contain_aodh_config('keystone_authtoken/auth_uri').with_value( 'https://foo.bar:1234/' )
+    context "with custom keystone identity_uri and auth_uri" do
+      before do
+        params.merge!({
+          :keystone_identity_uri => 'https://foo.bar:35357/',
+          :keystone_auth_uri => 'https://foo.bar:5000/v2.0/',
+        })
+      end
+      it 'configures identity_uri and auth_uri but deprecates old auth settings' do
+        is_expected.to contain_aodh_config('keystone_authtoken/identity_uri').with_value("https://foo.bar:35357/");
+        is_expected.to contain_aodh_config('keystone_authtoken/auth_uri').with_value("https://foo.bar:5000/v2.0/");
+      end
     end
   end
 
-  describe "with custom keystone identity_uri" do
-    let :facts do
-      @default_facts.merge({ :osfamily => 'RedHat' })
-    end
-    before do
-      params.merge!({
-        :keystone_identity_uri => 'https://foo.bar:1234/',
-      })
-    end
-    it 'configures identity_uri' do
-      is_expected.to contain_aodh_config('keystone_authtoken/identity_uri').with_value("https://foo.bar:1234/");
-    end
-  end
+  on_supported_os({
+    :supported_os   => OSDefaults.get_supported_os
+  }).each do |os,facts|
+    context "on #{os}" do
+      let (:facts) do
+        facts.merge!(OSDefaults.get_facts({
+          :fqdn           => 'some.host.tld',
+          :processorcount => 2,
+          :concat_basedir => '/var/lib/puppet/concat'
+        }))
+      end
 
-  describe "with custom keystone identity_uri and auth_uri" do
-    let :facts do
-      @default_facts.merge({ :osfamily => 'RedHat' })
-    end
-    before do
-      params.merge!({
-        :keystone_identity_uri => 'https://foo.bar:35357/',
-        :keystone_auth_uri => 'https://foo.bar:5000/v2.0/',
-      })
-    end
-    it 'configures identity_uri and auth_uri but deprecates old auth settings' do
-      is_expected.to contain_aodh_config('keystone_authtoken/identity_uri').with_value("https://foo.bar:35357/");
-      is_expected.to contain_aodh_config('keystone_authtoken/auth_uri').with_value("https://foo.bar:5000/v2.0/");
+      let(:platform_params) do
+        case facts[:osfamily]
+        when 'Debian'
+          { :api_package_name => 'aodh-api',
+            :api_service_name => 'aodh-api' }
+        when 'RedHat'
+          { :api_package_name => 'openstack-aodh-api',
+            :api_service_name => 'openstack-aodh-api' }
+        end
+      end
+      it_configures 'aodh-api'
     end
   end
 
diff --git a/spec/classes/aodh_auth_spec.rb b/spec/classes/aodh_auth_spec.rb
index 9813451c..2ff64a7c 100644
--- a/spec/classes/aodh_auth_spec.rb
+++ b/spec/classes/aodh_auth_spec.rb
@@ -36,20 +36,16 @@ describe 'aodh::auth' do
 
   end
 
-  context 'on Debian platforms' do
-    let :facts do
-      { :osfamily => 'Debian' }
+  on_supported_os({
+    :supported_os   => OSDefaults.get_supported_os
+  }).each do |os,facts|
+    context "on #{os}" do
+      let (:facts) do
+        facts.merge!(OSDefaults.get_facts())
+      end
+
+      it_configures 'aodh-auth'
     end
-
-    it_configures 'aodh-auth'
-  end
-
-  context 'on RedHat platforms' do
-    let :facts do
-      { :osfamily => 'RedHat' }
-    end
-
-    it_configures 'aodh-auth'
   end
 
 end
diff --git a/spec/classes/aodh_client_spec.rb b/spec/classes/aodh_client_spec.rb
index 8c43670f..748699d7 100644
--- a/spec/classes/aodh_client_spec.rb
+++ b/spec/classes/aodh_client_spec.rb
@@ -15,19 +15,16 @@ describe 'aodh::client' do
     end
   end
 
-  context 'on Debian platforms' do
-    let :facts do
-      { :osfamily => 'Debian' }
-    end
+  on_supported_os({
+    :supported_os   => OSDefaults.get_supported_os
+  }).each do |os,facts|
+    context "on #{os}" do
+      let (:facts) do
+        facts.merge!(OSDefaults.get_facts())
+      end
 
-    it_configures 'aodh client'
+      it_configures 'aodh client'
+    end
   end
 
-  context 'on RedHat platforms' do
-    let :facts do
-      { :osfamily => 'RedHat' }
-    end
-
-    it_configures 'aodh client'
-  end
 end
diff --git a/spec/classes/aodh_db_postgresql_spec.rb b/spec/classes/aodh_db_postgresql_spec.rb
index 437fdfc1..4f868625 100644
--- a/spec/classes/aodh_db_postgresql_spec.rb
+++ b/spec/classes/aodh_db_postgresql_spec.rb
@@ -10,15 +10,7 @@ describe 'aodh::db::postgresql' do
     'include postgresql::server'
   end
 
-  context 'on a RedHat osfamily' do
-    let :facts do
-      {
-        :osfamily                 => 'RedHat',
-        :operatingsystemrelease   => '7.0',
-        :concat_basedir => '/var/lib/puppet/concat'
-      }
-    end
-
+  shared_examples 'aodh::db::postgresql' do
     context 'with only required parameters' do
       let :params do
         req_params
@@ -32,27 +24,19 @@ describe 'aodh::db::postgresql' do
 
   end
 
-  context 'on a Debian osfamily' do
-    let :facts do
-      {
-        :operatingsystemrelease => '7.8',
-        :operatingsystem        => 'Debian',
-        :osfamily               => 'Debian',
-        :concat_basedir => '/var/lib/puppet/concat'
-      }
-    end
-
-    context 'with only required parameters' do
-      let :params do
-        req_params
+  on_supported_os({
+    :supported_os   => OSDefaults.get_supported_os
+  }).each do |os,facts|
+    context "on #{os}" do
+      let (:facts) do
+        facts.merge!(OSDefaults.get_facts({
+          :concat_basedir => '/var/lib/puppet/concat'
+        }))
       end
 
-      it { is_expected.to contain_postgresql__server__db('aodh').with(
-        :user     => 'aodh',
-        :password => 'md534e5dd092d680f3d8c11c62951fb5c19'
-      )}
+      it_configures 'aodh::db::postgresql'
     end
-
   end
 
+
 end
diff --git a/spec/classes/aodh_db_spec.rb b/spec/classes/aodh_db_spec.rb
index 07c906de..e78caa3c 100644
--- a/spec/classes/aodh_db_spec.rb
+++ b/spec/classes/aodh_db_spec.rb
@@ -87,16 +87,7 @@ describe 'aodh::db' do
     end
   end
 
-  context 'on Debian platforms' do
-    let :facts do
-      { :osfamily => 'Debian',
-        :operatingsystem => 'Debian',
-        :operatingsystemrelease => 'jessie',
-      }
-    end
-
-    it_configures 'aodh::db'
-
+  shared_examples_for 'aodh::db on Debian' do
     context 'with sqlite backend' do
       let :params do
         { :database_connection     => 'sqlite:///var/lib/aodh/aodh.sqlite', }
@@ -109,7 +100,6 @@ describe 'aodh::db' do
           :tag    => 'openstack'
         )
       end
-
     end
 
     context 'using pymysql driver' do
@@ -127,15 +117,7 @@ describe 'aodh::db' do
     end
   end
 
-  context 'on Redhat platforms' do
-    let :facts do
-      { :osfamily => 'RedHat',
-        :operatingsystemrelease => '7.1',
-      }
-    end
-
-    it_configures 'aodh::db'
-
+  shared_examples_for 'aodh::db on RedHat' do
     context 'using pymysql driver' do
       let :params do
         { :database_connection     => 'mysql+pymysql://aodh:aodh@localhost/aodh', }
@@ -144,5 +126,23 @@ describe 'aodh::db' do
       it { is_expected.not_to contain_package('aodh-backend-package') }
     end
   end
+
+  on_supported_os({
+    :supported_os   => OSDefaults.get_supported_os
+  }).each do |os,facts|
+    context "on #{os}" do
+      let (:facts) do
+        facts.merge!(OSDefaults.get_facts())
+      end
+
+      case facts[:osfamily]
+      when 'Debian'
+        it_configures 'aodh::db on Debian'
+      when 'RedHat'
+        it_configures 'aodh::db on RedHat'
+      end
+      it_configures 'aodh::db'
+    end
+  end
 end
 
diff --git a/spec/classes/aodh_evaluator_spec.rb b/spec/classes/aodh_evaluator_spec.rb
index 07450b76..471db05d 100644
--- a/spec/classes/aodh_evaluator_spec.rb
+++ b/spec/classes/aodh_evaluator_spec.rb
@@ -85,29 +85,31 @@ describe 'aodh::evaluator' do
     end
   end
 
-  context 'on Debian platforms' do
-    let :facts do
-      @default_facts.merge({ :osfamily => 'Debian' })
-    end
+  on_supported_os({
+    :supported_os   => OSDefaults.get_supported_os
+  }).each do |os,facts|
+    context "on #{os}" do
+      let (:facts) do
+        facts.merge!(OSDefaults.get_facts({
+          :fqdn           => 'some.host.tld',
+          :processorcount => 2,
+          :concat_basedir => '/var/lib/puppet/concat'
+        }))
+      end
 
-    let :platform_params do
-      { :evaluator_package_name => 'aodh-evaluator',
-        :evaluator_service_name => 'aodh-evaluator' }
+      let(:platform_params) do
+        case facts[:osfamily]
+        when 'Debian'
+          { :evaluator_package_name => 'aodh-evaluator',
+            :evaluator_service_name => 'aodh-evaluator' }
+        when 'RedHat'
+          { :evaluator_package_name => 'openstack-aodh-evaluator',
+            :evaluator_service_name => 'openstack-aodh-evaluator' }
+        end
+      end
+      it_configures 'aodh-evaluator'
     end
-
-    it_configures 'aodh-evaluator'
   end
 
-  context 'on RedHat platforms' do
-    let :facts do
-      @default_facts.merge({ :osfamily => 'RedHat' })
-    end
 
-    let :platform_params do
-      { :evaluator_package_name => 'openstack-aodh-evaluator',
-        :evaluator_service_name => 'openstack-aodh-evaluator' }
-    end
-
-    it_configures 'aodh-evaluator'
-  end
 end
diff --git a/spec/classes/aodh_init_spec.rb b/spec/classes/aodh_init_spec.rb
index 4ca9f3da..e0bbbbc8 100644
--- a/spec/classes/aodh_init_spec.rb
+++ b/spec/classes/aodh_init_spec.rb
@@ -212,31 +212,25 @@ describe 'aodh' do
     end
   end
 
-  context 'on Debian platforms' do
-    let :facts do
-      @default_facts.merge({
-        :osfamily => 'Debian',
-        :operatingsystem => 'Debian',
-      })
-    end
+  on_supported_os({
+    :supported_os   => OSDefaults.get_supported_os
+  }).each do |os,facts|
+    context "on #{os}" do
+      let (:facts) do
+        facts.merge!(OSDefaults.get_facts())
+      end
 
-    let :platform_params do
-      { :aodh_common_package => 'aodh-common' }
+      let(:platform_params) do
+        case facts[:osfamily]
+        when 'Debian'
+          { :aodh_common_package => 'aodh-common' }
+        when 'RedHat'
+          { :aodh_common_package => 'openstack-aodh-common' }
+        end
+      end
+      it_behaves_like 'aodh'
     end
-
-    it_behaves_like 'aodh'
   end
 
-  context 'on RedHat platforms' do
-    let :facts do
-      @default_facts.merge({ :osfamily => 'RedHat' })
-    end
-
-    let :platform_params do
-      { :aodh_common_package => 'openstack-aodh-common' }
-    end
-
-    it_behaves_like 'aodh'
-  end
 
 end
diff --git a/spec/classes/aodh_listener_spec.rb b/spec/classes/aodh_listener_spec.rb
index 32f1076e..f54d1e43 100644
--- a/spec/classes/aodh_listener_spec.rb
+++ b/spec/classes/aodh_listener_spec.rb
@@ -71,29 +71,27 @@ describe 'aodh::listener' do
     end
   end
 
-  context 'on Debian platforms' do
-    let :facts do
-      @default_facts.merge({ :osfamily => 'Debian' })
-    end
+  on_supported_os({
+    :supported_os   => OSDefaults.get_supported_os
+  }).each do |os,facts|
+    context "on #{os}" do
+      let (:facts) do
+        facts.merge!(OSDefaults.get_facts())
+      end
 
-    let :platform_params do
-      { :listener_package_name => 'aodh-listener',
-        :listener_service_name => 'aodh-listener' }
+      let(:platform_params) do
+        case facts[:osfamily]
+        when 'Debian'
+          { :listener_package_name => 'aodh-listener',
+            :listener_service_name => 'aodh-listener' }
+        when 'RedHat'
+          { :listener_package_name => 'openstack-aodh-listener',
+            :listener_service_name => 'openstack-aodh-listener' }
+        end
+      end
+      it_configures 'aodh-listener'
     end
-
-    it_configures 'aodh-listener'
   end
 
-  context 'on RedHat platforms' do
-    let :facts do
-      @default_facts.merge({ :osfamily => 'RedHat' })
-    end
 
-    let :platform_params do
-      { :listener_package_name => 'openstack-aodh-listener',
-        :listener_service_name => 'openstack-aodh-listener' }
-    end
-
-    it_configures 'aodh-listener'
-  end
 end
diff --git a/spec/classes/aodh_logging_spec.rb b/spec/classes/aodh_logging_spec.rb
index 4cb4f1a1..1281e20d 100644
--- a/spec/classes/aodh_logging_spec.rb
+++ b/spec/classes/aodh_logging_spec.rb
@@ -125,20 +125,16 @@ describe 'aodh::logging' do
       }
   end
 
-  context 'on Debian platforms' do
-    let :facts do
-      @default_facts.merge({ :osfamily => 'Debian' })
+  on_supported_os({
+    :supported_os   => OSDefaults.get_supported_os
+  }).each do |os,facts|
+    context "on #{os}" do
+      let (:facts) do
+        facts.merge!(OSDefaults.get_facts())
+      end
+
+      it_configures 'aodh-logging'
     end
-
-    it_configures 'aodh-logging'
-  end
-
-  context 'on RedHat platforms' do
-    let :facts do
-      @default_facts.merge({ :osfamily => 'RedHat' })
-    end
-
-    it_configures 'aodh-logging'
   end
 
 end
diff --git a/spec/classes/aodh_notifier_spec.rb b/spec/classes/aodh_notifier_spec.rb
index 6c786c2a..3bb88074 100644
--- a/spec/classes/aodh_notifier_spec.rb
+++ b/spec/classes/aodh_notifier_spec.rb
@@ -71,29 +71,26 @@ describe 'aodh::notifier' do
     end
   end
 
-  context 'on Debian platforms' do
-    let :facts do
-      @default_facts.merge({ :osfamily => 'Debian' })
-    end
+  on_supported_os({
+    :supported_os   => OSDefaults.get_supported_os
+  }).each do |os,facts|
+    context "on #{os}" do
+      let (:facts) do
+        facts.merge!(OSDefaults.get_facts())
+      end
 
-    let :platform_params do
-      { :notifier_package_name => 'aodh-notifier',
-        :notifier_service_name => 'aodh-notifier' }
+      let(:platform_params) do
+        case facts[:osfamily]
+        when 'Debian'
+          { :notifier_package_name => 'aodh-notifier',
+            :notifier_service_name => 'aodh-notifier' }
+        when 'RedHat'
+          { :notifier_package_name => 'openstack-aodh-notifier',
+            :notifier_service_name => 'openstack-aodh-notifier' }
+        end
+      end
+      it_configures 'aodh-notifier'
     end
-
-    it_configures 'aodh-notifier'
   end
 
-  context 'on RedHat platforms' do
-    let :facts do
-      @default_facts.merge({ :osfamily => 'RedHat' })
-    end
-
-    let :platform_params do
-      { :notifier_package_name => 'openstack-aodh-notifier',
-        :notifier_service_name => 'openstack-aodh-notifier' }
-    end
-
-    it_configures 'aodh-notifier'
-  end
 end
diff --git a/spec/classes/aodh_policy_spec.rb b/spec/classes/aodh_policy_spec.rb
index 9bce550a..6a45d2b3 100644
--- a/spec/classes/aodh_policy_spec.rb
+++ b/spec/classes/aodh_policy_spec.rb
@@ -23,19 +23,16 @@ describe 'aodh::policy' do
     end
   end
 
-  context 'on Debian platforms' do
-    let :facts do
-      { :osfamily => 'Debian' }
-    end
+  on_supported_os({
+    :supported_os   => OSDefaults.get_supported_os
+  }).each do |os,facts|
+    context "on #{os}" do
+      let (:facts) do
+        facts.merge!(OSDefaults.get_facts())
+      end
 
-    it_configures 'aodh policies'
+      it_configures 'aodh policies'
+    end
   end
 
-  context 'on RedHat platforms' do
-    let :facts do
-      { :osfamily => 'RedHat' }
-    end
-
-    it_configures 'aodh policies'
-  end
 end
diff --git a/spec/classes/aodh_wsgi_apache_spec.rb b/spec/classes/aodh_wsgi_apache_spec.rb
index 2cd2b44d..f6cfb6c6 100644
--- a/spec/classes/aodh_wsgi_apache_spec.rb
+++ b/spec/classes/aodh_wsgi_apache_spec.rb
@@ -2,14 +2,6 @@ require 'spec_helper'
 
 describe 'aodh::wsgi::apache' do
 
-  let :global_facts do
-    {
-      :processorcount => 42,
-      :concat_basedir => '/var/lib/puppet/concat',
-      :fqdn           => 'some.host.tld'
-    }
-  end
-
   shared_examples_for 'apache serving aodh with mod_wsgi' do
     it { is_expected.to contain_service('httpd').with_name(platform_parameters[:httpd_service_name]) }
     it { is_expected.to contain_class('aodh::params') }
@@ -81,44 +73,39 @@ describe 'aodh::wsgi::apache' do
     end
   end
 
-  context 'on RedHat platforms' do
-    let :facts do
-      global_facts.merge({
-        :osfamily               => 'RedHat',
-        :operatingsystemrelease => '7.0'
-      })
-    end
+  on_supported_os({
+    :supported_os   => OSDefaults.get_supported_os
+  }).each do |os,facts|
+    context "on #{os}" do
+      let (:facts) do
+        facts.merge!(OSDefaults.get_facts({
+          :processorcount => 42,
+          :concat_basedir => '/var/lib/puppet/concat',
+          :fqdn           => 'some.host.tld'
+        }))
+      end
 
-    let :platform_parameters do
-      {
-        :httpd_service_name => 'httpd',
-        :httpd_ports_file   => '/etc/httpd/conf/ports.conf',
-        :wsgi_script_path   => '/var/www/cgi-bin/aodh',
-        :wsgi_script_source => '/usr/lib/python2.7/site-packages/aodh/api/app.wsgi'
-      }
-    end
+      let(:platform_parameters) do
+        case facts[:osfamily]
+        when 'Debian'
+          {
+            :httpd_service_name => 'apache2',
+            :httpd_ports_file   => '/etc/apache2/ports.conf',
+            :wsgi_script_path   => '/usr/lib/cgi-bin/aodh',
+            :wsgi_script_source => '/usr/share/aodh-common/app.wsgi'
+          }
+        when 'RedHat'
+          {
+            :httpd_service_name => 'httpd',
+            :httpd_ports_file   => '/etc/httpd/conf/ports.conf',
+            :wsgi_script_path   => '/var/www/cgi-bin/aodh',
+            :wsgi_script_source => '/usr/lib/python2.7/site-packages/aodh/api/app.wsgi'
+          }
 
-    it_configures 'apache serving aodh with mod_wsgi'
+        end
+      end
+      it_configures 'apache serving aodh with mod_wsgi'
+    end
   end
 
-  context 'on Debian platforms' do
-    let :facts do
-      global_facts.merge({
-        :osfamily               => 'Debian',
-        :operatingsystem        => 'Debian',
-        :operatingsystemrelease => '7.0'
-      })
-    end
-
-    let :platform_parameters do
-      {
-        :httpd_service_name => 'apache2',
-        :httpd_ports_file   => '/etc/apache2/ports.conf',
-        :wsgi_script_path   => '/usr/lib/cgi-bin/aodh',
-        :wsgi_script_source => '/usr/share/aodh-common/app.wsgi'
-      }
-    end
-
-    it_configures 'apache serving aodh with mod_wsgi'
-  end
 end