Introducing ttl to openstack-telemetry

ttl is the time_to_live value that will be configured against database. This value
indicates the expiry time for ceilometer samples

Implements: bluerprint ceilometer-db-cleanup-configuration

Change-Id: I1c207e15ec0ca23c2fbd0db10842e600e71d69df

README.md

@@ -76,6 +76,7 @@ Attributes
 * `openstack['telemetry']['service-credentials']['cafile']` - A PEM encoded Certificate Authority to use when verifying HTTPs connections (for service polling authentication)
 * `openstack['telemetry']['service-credentials']['insecure']` - Set whether to verify HTTPS connections (for service polling authentication)
 * `openstack['telemetry']['dbsync_timeout']` - Set dbsync command timeout value
+* `openstack['telemetry']['database']['time_to_live']` - Set a time_to_live parameter (ttl) for samples. Set -1 for no expiry
 
 The following attributes are defined in attributes/default.rb of the common cookbook, but are documented here due to their relevance:
 

attributes/default.rb

@@ -143,3 +143,6 @@ when 'debian'
     'package_overrides' => "-o Dpkg::Options::='--force-confold' -o Dpkg::Options::='--force-confdef'"
   }
 end
+
+# The time to live value for samples which is specified in seconds, override to -1 if no data expiry is required
+default['openstack']['telemetry']['database']['time_to_live'] = 1800

spec/common_spec.rb

@@ -175,6 +175,13 @@ describe 'openstack-telemetry::common' do
         end
       end
 
+      context 'database' do
+        it 'has time_to_live set' do
+          expect(chef_run).to render_config_file(file.name)\
+            .with_section_content('database', /^time_to_live=1800$/)
+        end
+      end
+
       context 'service_credentials attributes with default values' do
         it 'sets cafile' do
           expect(chef_run).not_to render_file(file.name).with_content(/^os_cacert = $/)

templates/default/ceilometer.conf.erb

@@ -61,6 +61,7 @@ periodic_interval = <%= node["openstack"]["telemetry"]["periodic_interval"] %>
 
 [database]
 connection=<%= @database_connection %>
+time_to_live=<%= node["openstack"]["telemetry"]["database"]["time_to_live"] %>
 
 [api]
 host = <%= @api_bind_host %>