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 aodh module.

This patch also add unit tests for aodh::db class.

Change-Id: I3f9ed49b44a9a7c89be06f40a5823cc24a66066e

Author: sbadia

manifests/db.pp

@@ -43,6 +43,8 @@
   $database_max_overflow   = 20,
 ) {
 
+  include ::aodh::params
+
   $database_connection_real = pick($::aodh::database_connection, $database_connection)
   $database_idle_timeout_real = pick($::aodh::database_idle_timeout, $database_idle_timeout)
   $database_min_pool_size_real = pick($::aodh::database_min_pool_size, $database_min_pool_size)
@@ -62,7 +64,8 @@
         require 'mysql::bindings::python'
       }
       /^postgresql:\/\//: {
-        $backend_package = $::aodh::params::psycopg_package_name
+        $backend_package = false
+        require 'postgresql::lib::python'
       }
       /^sqlite:\/\//: {
         $backend_package = $::aodh::params::sqlite_package_name

spec/classes/aodh_db_spec.rb

@@ -0,0 +1,96 @@
+require 'spec_helper'
+
+describe 'aodh::db' do
+
+  shared_examples 'aodh::db' do
+
+    context 'with default parameters' do
+
+      it { is_expected.to contain_class('aodh::params') }
+      it { is_expected.to contain_aodh_config('database/connection').with_value('sqlite:////var/lib/aodh/aodh.sqlite') }
+      it { is_expected.to contain_aodh_config('database/idle_timeout').with_value('3600') }
+      it { is_expected.to contain_aodh_config('database/min_pool_size').with_value('1') }
+      it { is_expected.to contain_aodh_config('database/max_retries').with_value('10') }
+      it { is_expected.to contain_aodh_config('database/retry_interval').with_value('10') }
+
+    end
+
+    context 'with specific parameters' do
+      let :params do
+        { :database_connection     => 'mysql://aodh:aodh@localhost/aodh',
+          :database_idle_timeout   => '3601',
+          :database_min_pool_size  => '2',
+          :database_max_retries    => '11',
+          :database_retry_interval => '11',
+        }
+      end
+
+      it { is_expected.to contain_class('aodh::params') }
+      it { is_expected.to contain_aodh_config('database/connection').with_value('mysql://aodh:aodh@localhost/aodh').with_secret(true) }
+      it { is_expected.to contain_aodh_config('database/idle_timeout').with_value('3601') }
+      it { is_expected.to contain_aodh_config('database/min_pool_size').with_value('2') }
+      it { is_expected.to contain_aodh_config('database/max_retries').with_value('11') }
+      it { is_expected.to contain_aodh_config('database/retry_interval').with_value('11') }
+
+    end
+
+    context 'with postgresql backend' do
+      let :params do
+        { :database_connection     => 'postgresql://localhost:1234/aodh', }
+      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     => 'redis://aodh:aodh@localhost/aodh', }
+      end
+
+      it_raises 'a Puppet::Error', /validate_re/
+    end
+
+  end
+
+  context 'on Debian platforms' do
+    let :facts do
+      { :osfamily => 'Debian',
+        :operatingsystem => 'Debian',
+        :operatingsystemrelease => 'jessie',
+      }
+    end
+
+    it_configures 'aodh::db'
+
+    context 'with sqlite backend' do
+      let :params do
+        { :database_connection     => 'sqlite:///var/lib/aodh/aodh.sqlite', }
+      end
+
+      it 'install the proper backend package' do
+        is_expected.to contain_package('aodh-backend-package').with(
+          :ensure => 'present',
+          :name   => 'python-pysqlite2',
+          :tag    => 'openstack'
+        )
+      end
+
+    end
+  end
+
+  context 'on Redhat platforms' do
+    let :facts do
+      { :osfamily => 'RedHat',
+        :operatingsystemrelease => '7.1',
+      }
+    end
+
+    it_configures 'aodh::db'
+  end
+
+end
+