Allow tuning cache timeout

This allows users to tune cache timeout in Django.

Change-Id: I18cf8d80074203c044e69609dd7f713f6a2a593d

manifests/init.pp

@@ -35,6 +35,10 @@
 #   (optional) A hash of parameters to enable specific cache options.
 #   Defaults to undef
 #
+#  [*cache_timeout*]
+#   (optional) The default timeout, in seconds, to use for the cache.
+#   Defaults to undef
+#
 #  [*cache_server_url*]
 #    (optional) URL of a cache server.
 #    This allows arbitrary strings to be set as CACHE BACKEND LOCATION.
@@ -567,6 +571,7 @@ class horizon(
   $package_ensure                      = 'present',
   $cache_backend                       = 'django.core.cache.backends.locmem.LocMemCache',
   $cache_options                       = undef,
+  $cache_timeout                       = undef,
   $cache_server_url                    = undef,
   $cache_server_ip                     = undef,
   $cache_server_port                   = '11211',

releasenotes/notes/cache_timeout-40252b507b11e4e5.yaml

@@ -0,0 +1,4 @@
+---
+features:
+  - |
+    The new ``horizon::cache_timeout`` parameter has been added.

spec/classes/horizon_init_spec.rb

@@ -99,6 +99,7 @@ describe 'horizon' do
       before do
         params.merge!({
           :cache_backend                    => 'django.core.cache.backends.memcached.MemcachedCache',
+          :cache_timeout                    => 300,
           :cache_options                    => {'SOCKET_TIMEOUT' => 1,'SERVER_RETRIES' => 1,'DEAD_RETRY' => 1},
           :cache_server_ip                  => '10.0.0.1',
           :django_session_engine            => 'django.contrib.sessions.backends.cache',
@@ -166,6 +167,7 @@ describe 'horizon' do
           "            'SOCKET_TIMEOUT': 1,",
           "        'BACKEND': 'django.core.cache.backends.memcached.MemcachedCache',",
           "        'LOCATION': '10.0.0.1:11211',",
+          "        'TIMEOUT': 300,",
           'SESSION_ENGINE = "django.contrib.sessions.backends.cache"',
           'OPENSTACK_KEYSTONE_URL = "https://keystone.example.com:4682"',
           'OPENSTACK_KEYSTONE_DEFAULT_ROLE = "SwiftOperator"',

templates/local_settings.py.erb

@@ -240,6 +240,9 @@ CACHES = {
         'LOCATION': '<%= @cache_server_url %>',
         <%- end -%>
     <%- end -%>
+    <%- if @cache_timeout -%>
+        'TIMEOUT': <%= @cache_timeout %>,
+    <%- end -%>
     }
 }