Merge "Fix volume caching in PowerFlex driver"

cinder/tests/unit/volume/drivers/dell_emc/powerflex/__init__.py

@@ -69,12 +69,14 @@ class TestPowerFlexDriver(test.TestCase):
         Invalid='1',
         BadStatus='2',
         ValidVariant='3',
+        BadStatusWithDetails='4',
     ))
     __RESPONSE_MODE_NAMES = {
         '0': 'Valid',
         '1': 'Invalid',
         '2': 'BadStatus',
         '3': 'ValidVariant',
+        '4': 'BadStatusWithDetails',
     }
 
     BAD_STATUS_RESPONSE = mocks.MockHTTPSResponse(
@@ -175,6 +177,7 @@ class TestPowerFlexDriver(test.TestCase):
         RESPONSE_MODE.Valid: Respond with valid data
         RESPONSE_MODE.Invalid: Respond with invalid data
         RESPONSE_MODE.BadStatus: Response with not-OK status code.
+        RESPONSE_MODE.BadStatusWithDetails: as BadStatus but with "details".
         """
         self.__https_response_mode = mode
 

cinder/tests/unit/volume/drivers/dell_emc/powerflex/test_create_snapshot.py

@@ -24,6 +24,7 @@ from cinder.tests.unit import fake_snapshot
 from cinder.tests.unit import fake_volume
 from cinder.tests.unit.volume.drivers.dell_emc import powerflex
 from cinder.tests.unit.volume.drivers.dell_emc.powerflex import mocks
+from cinder.volume.drivers.dell_emc.powerflex import rest_client
 from cinder.volume.drivers.dell_emc.powerflex import utils as flex_utils
 
 
@@ -84,6 +85,20 @@ class TestCreateSnapShot(powerflex.TestPowerFlexDriver):
                 'instances/System/action/snapshotVolumes':
                     self.BAD_STATUS_RESPONSE,
             },
+            self.RESPONSE_MODE.BadStatusWithDetails: {
+                'instances/System/action/snapshotVolumes':
+                    mocks.MockHTTPSResponse(
+                        {
+                            'errorCode': 0,
+                            'message': 'Error with details',
+                            'details': [
+                                {
+                                    'rc': rest_client.TOO_MANY_SNAPS_ERROR,
+                                },
+                            ],
+                        }, 500
+                    ),
+            },
             self.RESPONSE_MODE.Invalid: {
                 'types/Volume/instances/getByName::' +
                 self.volume_name_2x_enc: None,
@@ -116,3 +131,12 @@ class TestCreateSnapShot(powerflex.TestPowerFlexDriver):
     def test_create_snapshot(self):
         self.set_https_response_mode(self.RESPONSE_MODE.Valid)
         self.driver.create_snapshot(self.snapshot)
+
+    def test_create_snapshot_limit_reached(self):
+        self.set_https_response_mode(
+            self.RESPONSE_MODE.BadStatusWithDetails)
+        self.assertRaises(
+            exception.SnapshotLimitReached,
+            self.driver.create_snapshot,
+            self.snapshot
+        )

cinder/volume/drivers/dell_emc/powerflex/rest_client.py

@@ -35,8 +35,11 @@ VOLUME_MIGRATION_IN_PROGRESS_ERROR = 717
 VOLUME_MIGRATION_ALREADY_ON_DESTINATION_POOL_ERROR = 718
 VOLUME_NOT_FOUND_ERROR = 79
 OLD_VOLUME_NOT_FOUND_ERROR = 78
+TOO_MANY_SNAPS_ERROR = 182
 ILLEGAL_SYNTAX = 0
 
+MAX_SNAPS_IN_VTREE = 126
+
 
 class RestClient(object):
     def __init__(self, configuration, is_primary=True):
@@ -214,6 +217,11 @@ class RestClient(object):
                    {"vol_name": volume_provider_id,
                     "response": response["message"]})
             LOG.error(msg)
+            # check if the volume reached snapshot limit
+            if ("details" in response and
+                    response["details"][0]["rc"] == TOO_MANY_SNAPS_ERROR):
+                raise exception.SnapshotLimitReached(
+                    set_limit=MAX_SNAPS_IN_VTREE)
             raise exception.VolumeBackendAPIException(data=msg)
         return response["volumeIdList"][0]
 

releasenotes/notes/fix-powerflex-volume-cache-da3fa1769ef78ae8.yaml

@@ -0,0 +1,10 @@
+---
+fixes:
+  - |
+    PowerFlex driver `bug #1942095
+    <https://bugs.launchpad.net/cinder/+bug/1942095>`_: Fixed Cinder
+    volume caching mechanism for the driver. Now the driver
+    correctly raises ``exception.SnapshotLimitReached`` when maximum
+    snapshots are created for a given volume and a volume cache is
+    invalidated to allow a new row of fast volume clones.
+