[Pure Storage] Cinder manage quota breach deletion fix

This patch fixes an issue where when a tenant attempts to manage a volume
that exceeds their storage quota, the clenup will cause an error due
to attemptinmg to delete a non-existant volume on the backend.

Closes-Bug: #2119059
Change-Id: I57acda3d94af703b52bfc923a4928b089475b476
Signed-off-by: Simon Dodsley <simon@purestorage.com>

cinder/volume/drivers/pure.py

@@ -971,8 +971,10 @@ class PureBaseVolumeDriver(san.SanDriver):
         current_array = self._get_current_array()
         # Do a pass over remaining connections on the current array, if
         # we can try and remove any remote connections too.
-        hosts = list(current_array.get_connections(
-            volume_names=[vol_name]).items)
+        hosts = []
+        res = current_array.get_connections(volume_names=[vol_name])
+        if res.status_code == 200:
+            hosts = list(res.items)
         for host_info in range(0, len(hosts)):
             host_name = hosts[host_info].host.name
             self._disconnect_host(current_array, host_name, vol_name)
@@ -981,8 +983,6 @@ class PureBaseVolumeDriver(san.SanDriver):
         res = current_array.patch_volumes(names=[vol_name],
                                           volume=flasharray.VolumePatch(
                                               destroyed=True))
-        if self.configuration.pure_eradicate_on_delete:
-            current_array.delete_volumes(names=[vol_name])
         if res.status_code == 400:
             with excutils.save_and_reraise_exception() as ctxt:
                 if ERR_MSG_NOT_EXIST in res.errors[0].message:
@@ -990,6 +990,8 @@ class PureBaseVolumeDriver(san.SanDriver):
                     ctxt.reraise = False
                     LOG.warning("Volume deletion failed with message: %s",
                                 res.errors[0].message)
+        if self.configuration.pure_eradicate_on_delete:
+            current_array.delete_volumes(names=[vol_name])
         # Now check to see if deleting this volume left an empty volume
         # group. If so, we delete / eradicate the volume group
         if "/" in vol_name:

releasenotes/notes/pure_manage_quota_delete-dd24495e883498e7.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    Pure Storage driver `Bug #21119059 <https://bugs.launchpad.net/cinder/+bug/2119059>`_: Fixed
+    volume deletion issue when attempting to manage a new volume that exceeds the tenants
+    storage quota.