[cinder-ceph-k8s] enable image volume cache

Add options in cinder-ceph to enable image volume
cache and set cache max size and max count.
Update cinder conf for cinder-volume service in
cinder-ceph-k8s.

Change-Id: I3847a0a313d1b94ea3be4ec77c3024c804289258

charms/cinder-ceph-k8s/config.yaml

@@ -250,3 +250,19 @@ options:
     type: boolean
     default: False
     description: Enable notifications to send to telemetry.
+  image-volume-cache-enabled:
+    type: boolean
+    default: False
+    description: |
+      Enable the image volume cache.
+  image-volume-cache-max-size-gb:
+    type: int
+    default: 0
+    description: |
+      Max size of the image volume cache in GB. 0 means unlimited.
+  image-volume-cache-max-count:
+    type: int
+    default: 0
+    description: |
+      Max number of entries allowed in the image volume cache. 0 means
+      unlimited.

charms/cinder-ceph-k8s/metadata.yaml

@@ -39,6 +39,9 @@ requires:
   database:
     interface: mysql_client
     limit: 1
+  identity-credentials:
+    interface: keystone-credentials
+    optional: true
 
 provides:
   ceph-access:

charms/cinder-ceph-k8s/src/templates/cinder.conf.j2

@@ -18,6 +18,13 @@ transport_url = {{ amqp.transport_url }}
 enabled_backends = {{ cinder_ceph.backend_name }}
 cluster = {{ cinder_ceph.cluster_name }}
 
+{% if identity_credentials and identity_credentials.project_id -%}
+cinder_internal_tenant_project_id = {{ identity_credentials.project_id }}
+{% endif -%}
+{% if identity_credentials and identity_credentials.username -%}
+cinder_internal_tenant_user_id = {{ identity_credentials.username }}
+{% endif -%}
+
 [database]
 {% if database.connection -%}
 connection = {{ database.connection }}
@@ -37,8 +44,12 @@ rbd_pool = {{ cinder_ceph.rbd_pool }}
 rbd_user = {{ cinder_ceph.rbd_user }}
 rbd_secret_uuid = {{ cinder_ceph.secret_uuid }}
 
-{% if cinder_ceph.backend_availability_zone %}
+{% if cinder_ceph.backend_availability_zone -%}
 backend_availability_zone = {{ cinder_ceph.backend_availability_zone }}
-{% endif %}
+{% endif -%}
+
+image_volume_cache_enabled = {{ options.image_volume_cache_enabled }}
+image_volume_cache_max_size_gb = {{ options.image_volume_cache_max_size_gb }}
+image_volume_cache_max_count = {{ options.image_volume_cache_max_count }}
 
 {% include "parts/section-oslo-messaging-rabbit" %}

tests/ceph/smoke.yaml.j2

@@ -132,6 +132,8 @@ relations:
   - rabbitmq:amqp
 - - cinder:storage-backend
   - cinder-ceph:storage-backend
+- - keystone:identity-credentials
+  - cinder-ceph:identity-credentials
 
 - - mysql:database
   - gnocchi:database