Add configuration option to support testing on cloud-instances.

config.yaml

@@ -108,6 +108,16 @@ options:
       If True, charm will attempt to remove missing physical volumes from
       volume group, even when logical volumes are allocated on them. This
       option overrides 'remove-missing' when set.
+  ephemeral-unmount:
+    type: string
+    default:
+    description: |
+      Cloud instances provide ephermeral storage which is normally mounted
+      on /mnt.
+      .
+      Providing this option will force an unmount of the ephemeral device
+      so that it can be used as a Cinder storage device.  This is useful for
+      testing purposes (cloud deployment is not a typical use case).
   database-user:
     default: cinder
     type: string

hooks/cinder_hooks.py

@@ -26,6 +26,7 @@ from cinder_utils import (
     ceph_config_file,
     setup_ipv6,
     check_db_initialised,
+    filesystem_mounted,
 )
 
 from charmhelpers.core.hookenv import (
@@ -53,6 +54,7 @@ from charmhelpers.core.host import (
     lsb_release,
     restart_on_change,
     service_reload,
+    umount,
 )
 
 from charmhelpers.contrib.openstack.utils import (
@@ -123,6 +125,10 @@ def config_changed():
         sync_db_with_multi_ipv6_addresses(config('database'),
                                           config('database-user'))
 
+    e_mountpoint = conf['ephemeral-unmount']
+    if e_mountpoint and filesystem_mounted(e_mountpoint):
+        umount(e_mountpoint)
+
     if (service_enabled('volume') and
             conf['block-device'] not in [None, 'None', 'none']):
         block_devices = conf['block-device'].split()

hooks/cinder_utils.py

@@ -796,3 +796,7 @@ def git_post_install(projects_yaml):
     service_restart('tgtd')
 
     [service_restart(s) for s in services()]
+
+
+def filesystem_mounted(fs):
+    return subprocess.call(['grep', '-wqs', fs, '/proc/mounts']) == 0

tests/basic_deployment.py

@@ -68,7 +68,8 @@ class CinderBasicDeployment(OpenStackAmuletDeployment):
         """Configure all of the services."""
         cinder_config = {'block-device': 'vdb',
                          'glance-api-version': '2',
-                         'overwrite': 'true'}
+                         'overwrite': 'true',
+                         'ephemeral-unmount': '/mnt'}
         if self.git:
             amulet_http_proxy = os.environ.get('AMULET_HTTP_PROXY')