[billy-olsen,r=] Use region information from nova-cloud-controller.

Use the region provided by in the cloud-compute relation in order
to determine which region this node should be hosted in. This enables
the os_region_name value to be set in appropriate services so that
compute can properly access services in the same region.

Closes-Bug: #1421105

hooks/nova_compute_context.py

@@ -248,6 +248,14 @@ class CloudComputeContext(context.OSContextGenerator):
                                               rid=rid, unit=unit)
         return volume_service
 
+    @property
+    def region(self):
+        region = None
+        for rid in relation_ids('cloud-compute'):
+            for unit in related_units(rid):
+                region = relation_get('region', rid=rid, unit=unit)
+        return region
+
     def flat_dhcp_context(self):
         ec2_host = None
         for rid in relation_ids('cloud-compute'):
@@ -400,6 +408,11 @@ class CloudComputeContext(context.OSContextGenerator):
 
         if self.restart_trigger():
             ctxt['restart_trigger'] = self.restart_trigger()
+
+        region = self.region
+        if region:
+            ctxt['region'] = region
+
         return ctxt
 
 

templates/icehouse/nova.conf

@@ -113,6 +113,9 @@ network_device_mtu = {{ network_device_mtu }}
 
 {% if volume_service -%}
 volume_api_class = nova.volume.cinder.API
+{% if region -%}
+os_region_name = {{ region }}
+{% endif -%}
 {% endif -%}
 
 {% if user_config_flags -%}

templates/juno/nova.conf

@@ -167,3 +167,6 @@ live_migration_uri = {{ live_migration_uri }}
 {% if disk_cachemodes -%}
 disk_cachemodes = {{ disk_cachemodes }}
 {% endif -%}
+
+{% include "parts/cinder" %}
+

templates/kilo/nova.conf

@@ -180,6 +180,8 @@ disk_cachemodes = {{ disk_cachemodes }}
 
 {% include "section-rabbitmq-oslo" %}
 
+{% include "parts/cinder" %}
+
 [oslo_concurrency]
 lock_path=/var/lock/nova
 

templates/parts/cinder

@@ -0,0 +1,5 @@
+{% if volume_service and volume_service == 'cinder' and region -%}
+[cinder]
+os_region_name = {{ region }}
+{% endif -%}
+