db: Use postgresql lib class for psycopg package

This patch introduce the same design than mysql for postgresql
by requiring dedicated lib::python class instead of declaring
a new resource package within murano module.

Change-Id: I827c58174f235c7e3fafd9701a5b2fad261f2c4f

manifests/db.pp

@@ -62,7 +62,7 @@ class murano::db (
       require mysql::bindings::python
     }
     /^postgresql:\/\//: {
-      $backend_package = $::murano::params::psycopg_package_name
+      $backend_package = false
       require postgresql::lib::python
     }
     default: {

manifests/params.pp

@@ -14,7 +14,6 @@ class murano::params {
       $engine_package_name       = 'openstack-murano-engine'
       $pythonclient_package_name = 'openstack-python-muranoclient'
       $dashboard_package_name    = 'openstack-murano-dashboard'
-      $psycopg_package_name      = 'python-psycopg2'
       # service names
       $api_service_name          = 'murano-api'
       $engine_service_name       = 'murano-engine'
@@ -28,7 +27,6 @@ class murano::params {
       $engine_package_name       = 'murano-engine'
       $pythonclient_package_name = 'python-muranoclient'
       $dashboard_package_name    = 'python-murano-dashboard'
-      $psycopg_package_name      = 'python-psycopg2'
       # service names
       $api_service_name          = 'murano-api'
       $engine_service_name       = 'murano-engine'

spec/classes/murano_db_spec.rb

@@ -34,6 +34,17 @@ describe 'murano::db' do
       it { is_expected.to contain_murano_config('database/max_overflow').with_value('21') }
     end
 
+    context 'with postgresql backend' do
+      let :params do
+        { :database_connection     => 'postgresql://murano:murano@localhost/murano', }
+      end
+
+      it 'install the proper backend package' do
+        is_expected.to contain_package('python-psycopg2').with(:ensure => 'present')
+      end
+
+    end
+
     context 'with incorrect database_connection string' do
       let :params do
         { :database_connection     => 'sqlite://murano:murano@localhost/murano', }
@@ -45,7 +56,10 @@ describe 'murano::db' do
 
   context 'on Debian platforms' do
     let :facts do
-      { :osfamily => 'Debian' }
+      { :osfamily => 'Debian',
+        :operatingsystem => 'Debian',
+        :operatingsystemrelease => 'jessie',
+      }
     end
 
     it_configures 'murano::db'
@@ -53,10 +67,12 @@ describe 'murano::db' do
 
   context 'on Redhat platforms' do
     let :facts do
-      { :osfamily => 'RedHat' }
+      { :osfamily => 'RedHat',
+        :operatingsystemrelease => '7.1',
+      }
     end
 
     it_configures 'murano::db'
   end
 
-end
+end