[niedbalski,r=billy-olsen] Add api_workers option to allow the number of

workers available to be configured.

Closes-Bug: 1473222

ceilometer_contexts.py

@@ -78,6 +78,7 @@ class CeilometerContext(OSContextGenerator):
         from ceilometer_utils import get_shared_secret
 
         ctxt = {
+            'api_workers': config('api-workers'),
             'port': CEILOMETER_PORT,
             'metering_secret': get_shared_secret()
         }

config.yaml

@@ -146,3 +146,8 @@ options:
     description: |
       Default multicast port number that will be used to communicate between
       HA Cluster nodes.
+  api-workers:
+    type: int
+    default: 1
+    description: | 
+      Number of workers for Ceilometer API server. (>= Kilo).

templates/kilo/ceilometer.conf

@@ -0,0 +1,43 @@
+# kilo
+###############################################################################
+# [ WARNING ]
+# ceilometer configuration file maintained by Juju
+# local changes may be overwritten.
+###############################################################################
+[DEFAULT]
+debug = {{ debug }}
+verbose = {{ verbose }}
+use_syslog = {{ use_syslog }}
+api_workers = {{ api_workers }}
+
+{% include "parts/rabbitmq" -%}
+
+[api]
+port = {{ port }}
+
+[service_credentials]
+os_auth_url = {{ service_protocol }}://{{ service_host }}:{{ service_port }}/v2.0
+os_tenant_name = {{ admin_tenant_name }}
+os_username = {{ admin_user }}
+os_password = {{ admin_password }}
+
+[database]
+{% if db_replset: -%}
+connection = mongodb://{{ db_mongo_servers }}/{{ db_name }}?readPreference=primaryPreferred&replicaSet={{ db_replset }}
+mongodb_replica_set = {{ db_replset }}
+{% else -%}
+connection = mongodb://{{ db_host }}:{{ db_port }}/{{ db_name }}
+{% endif %}
+
+[publisher_rpc]
+metering_secret = {{ metering_secret }}
+
+[keystone_authtoken]
+auth_uri = {{ service_protocol }}://{{ service_host }}:{{ service_port }}/
+auth_host = {{ auth_host }}
+auth_port = {{ auth_port }}
+auth_protocol = {{ auth_protocol }}
+admin_tenant_name = {{ admin_tenant_name }}
+admin_user = {{ admin_user }}
+admin_password = {{ admin_password }}
+signing_dir = {{ signing_dir }}

unit_tests/test_ceilometer_contexts.py

@@ -111,8 +111,11 @@ class CeilometerContextsTest(CharmTestCase):
     @patch.object(utils, 'get_shared_secret')
     def test_ceilometer_context(self, secret):
         secret.return_value = 'mysecret'
-        self.assertEquals(contexts.CeilometerContext()(),
-                          {'port': 8777, 'metering_secret': 'mysecret'})
+        self.assertEquals(contexts.CeilometerContext()(), {
+            'port': 8777,
+            'metering_secret': 'mysecret',
+            'api_workers': 1,
+        })
 
     def test_ceilometer_service_context(self):
         self.relation_ids.return_value = ['ceilometer-service:0']