Support pylibmc and memcache cache backend

Install relevant package for pylibmc and
memcache backend.

Depends-on: I4e965b6f5449a7104677f93b00af77ae21cba94b

Change-Id: I2e6a705971761754c59b4069b5dfdfd1dfd7f00f

manifests/cache.pp

@@ -129,6 +129,8 @@ define oslo::cache(
   $memcache_pool_connection_get_timeout = $::os_service_default,
 ){
 
+  include ::oslo::params
+
   if !is_service_default($backend_argument) {
     $backend_argument_orig = join(any2array($backend_argument), ',')
   } else {
@@ -147,6 +149,20 @@ define oslo::cache(
     $proxies_orig = $proxies
   }
 
+  if ($backend =~ /pylibmc/ ) {
+    ensure_packages('python-pylibmc', {
+      ensure => present,
+      name   => $::oslo::params::pylibmc_package_name,
+      tag    => 'openstack',
+    })
+  } elsif ($backend =~ /\.memcache/ ) {
+    ensure_packages('python-memcache', {
+      ensure => present,
+      name   => $::oslo::params::python_memcache_package_name,
+      tag    => ['openstack', 'keystone-package'],
+    })
+  }
+
   $cache_options = {
     'cache/config_prefix'                        => { value => $config_prefix },
     'cache/expiration_time'                      => { value => $expiration_time },

manifests/params.pp

@@ -4,14 +4,18 @@ class oslo::params {
 
   case $::osfamily {
     'RedHat': {
-      $sqlite_package_name  = undef
-      $pymysql_package_name = undef
-      $pymongo_package_name = 'python-pymongo'
+      $sqlite_package_name          = undef
+      $pymysql_package_name         = undef
+      $pymongo_package_name         = 'python-pymongo'
+      $pylibmc_package_name         = 'python-pylibmc'
+      $python_memcache_package_name = 'python-memcached'
     }
     'Debian': {
-      $sqlite_package_name  = 'python-pysqlite2'
-      $pymysql_package_name = 'python-pymysql'
-      $pymongo_package_name = 'python-pymongo'
+      $sqlite_package_name          = 'python-pysqlite2'
+      $pymysql_package_name         = 'python-pymysql'
+      $pymongo_package_name         = 'python-pymongo'
+      $pylibmc_package_name         = 'python-pylibmc'
+      $python_memcache_package_name = 'python-memcache'
     }
     default: {
       fail("Unsupported osfamily: ${::osfamily} operatingsystem")

spec/defines/oslo_cache_spec.rb

@@ -60,6 +60,40 @@ describe 'oslo::cache' do
       end
     end
 
+    context 'with pylibmc backend' do
+      let :params do
+        {
+          :backend => 'dogpile.cache.pylibmc',
+        }
+      end
+
+      it 'configures cache backend' do
+        is_expected.to contain_keystone_config('cache/backend').with_value('dogpile.cache.pylibmc')
+        is_expected.to contain_package('python-pylibmc').with(
+          :ensure => 'present',
+          :name   => platform_params[:pylibmc_package_name],
+          :tag    => 'openstack',
+        )
+      end
+    end
+
+    context 'with memcache backend' do
+      let :params do
+        {
+          :backend => 'dogpile.cache.memcache',
+        }
+      end
+
+      it 'configures cache backend' do
+        is_expected.to contain_keystone_config('cache/backend').with_value('dogpile.cache.memcache')
+        is_expected.to contain_package('python-memcache').with(
+          :ensure => 'present',
+          :name   => platform_params[:python_memcache_package_name],
+          :tag    => ['openstack', 'keystone-package'],
+        )
+      end
+    end
+
     context 'with string in list parameters' do
       let :params do
         {
@@ -84,6 +118,19 @@ describe 'oslo::cache' do
       let (:facts) do
         facts.merge!(OSDefaults.get_facts())
       end
+      let(:platform_params) do
+        platform_params = { :pylibmc_package_name => 'python-pylibmc' }
+
+        case facts[:osfamily]
+        when 'Debian'
+          platform_params[:python_memcache_package_name] = 'python-memcache'
+        when 'RedHat'
+          platform_params[:python_memcache_package_name] = 'python-memcached'
+        end
+
+        platform_params
+      end
+
       it_behaves_like 'oslo-cache'
     end
   end