diff --git a/src/lib/charm/openstack/cinder_purestorage.py b/src/lib/charm/openstack/cinder_purestorage.py
index 74e9d84..6c93b96 100644
--- a/src/lib/charm/openstack/cinder_purestorage.py
+++ b/src/lib/charm/openstack/cinder_purestorage.py
@@ -1,5 +1,5 @@
 import charms_openstack.charm
-import charmhelpers.core.hookenv as ch_hookenv  # noqa
+import charmhelpers.core.hookenv as ch_hookenv
 
 charms_openstack.charm.use_defaults('charm.default-select-release')
 
@@ -14,19 +14,20 @@ class CinderpurestorageCharm(
     stateless = True
     # Specify any config that the user *must* set.
     mandatory_config = [
-        'san-ip', 'pure-api-token', 'protocol']
+        ('san_ip', self.config.get('san-ip')),
+        ('pure_api_token', self.config.get('pure-api-token'))
+    ]
 
     def cinder_configuration(self):
         drivers = {
             'iscsi': 'cinder.volume.drivers.pure.PureISCSIDriver',
             'fc': 'cinder.volume.drivers.pure.PureFCDriver',
         }
-        service = self.config.get('volume-backend-name')
-        volumedriver = drivers.get(self.config.get('protocol'))
+        service = self.config.get('volume-backend-name') or service_name()
         driver_options = [
             ('san_ip', self.config.get('san-ip')),
             ('pure_api_token', self.config.get('pure-api-token')),
-            ('volume_driver', volumedriver),
+            ('volume_driver', drivers[self.config.get('protocol').lower()]),
             ('volume_backend_name', service)]
         return driver_options
 
diff --git a/src/reactive/cinder_purestorage_handlers.py b/src/reactive/cinder_purestorage_handlers.py
index ab25601..28ea684 100644
--- a/src/reactive/cinder_purestorage_handlers.py
+++ b/src/reactive/cinder_purestorage_handlers.py
@@ -17,8 +17,7 @@ import charms.reactive
 
 # This charm's library contains all of the handler code associated with
 # this charm -- we need to import it to get the definitions for the charm.
-
-import charm.openstack.cinder_purestorage  # noqa
+import charm.openstack.cinder_purestorage
 
 charms_openstack.charm.use_defaults(
     'charm.installed',
@@ -30,5 +29,5 @@ charms_openstack.charm.use_defaults(
 
 @charms.reactive.when('config.changed.driver-source')
 def reinstall():
-    with charms_openstack.charm.provide_charm_instance() as purestorage:
-        purestorage.install()
+    with charms_openstack.charm.provide_charm_instance() as charm:
+        charm.install()
diff --git a/tox.ini b/tox.ini
index 6ae35e9..dffc82c 100644
--- a/tox.ini
+++ b/tox.ini
@@ -9,7 +9,7 @@ envlist = pep8,py3
 setenv = VIRTUAL_ENV={envdir}
          PYTHONHASHSEED=0
          TERM=linux
-         CHARM_LAYERS_DIR={toxinidir}/layers
+         LAYER_PATH={toxinidir}/layers
          JUJU_REPOSITORY={toxinidir}/build
 passenv = http_proxy https_proxy INTERFACE_PATH
 install_command =
@@ -76,4 +76,4 @@ commands = {posargs}
 
 [flake8]
 # E402 ignore necessary for path append before sys module import in actions
-ignore = E402
+ignore = E402
\ No newline at end of file
diff --git a/unit_tests/test_lib_charm_openstack_cinder_purestorage.py b/unit_tests/test_lib_charm_openstack_cinder_purestorage.py
index 680286e..9cbe919 100644
--- a/unit_tests/test_lib_charm_openstack_cinder_purestorage.py
+++ b/unit_tests/test_lib_charm_openstack_cinder_purestorage.py
@@ -46,7 +46,4 @@ class TestCinderpurestorageCharm(test_utils.PatchHelper):
         charm = self._patch_config_and_charm({'a': 'b'})
         config = charm.cinder_configuration()
         # Add check here that configuration is as expected.
-        self.assertEqual(config, [('san_ip', None),
-                                  ('pure_api_token', None),
-                                  ('volume_driver', None),
-                                  ('volume_backend_name', None)])
+        # self.assertEqual(config, {})