Adjusted format for pep8 and added tox.ini unit tests with stestr

requirements-dev.txt

@@ -2,3 +2,4 @@
 nose==1.3.7
 coverage
 flake8
+stestr>=2.2.0

src/charm.py

@@ -8,6 +8,7 @@ import logging
 from ops.charm import CharmBase
 from ops.main import main
 from ops.framework import StoredState
+from ops.model import MaintenanceStatus, ActiveStatus
 
 from charmhelpers.fetch.ubuntu import apt_install, apt_purge
 
@@ -35,7 +36,6 @@ def CinderThreeParContext(charm_config, service):
     }
 
 
-
 class CharmCinderThreeParCharm(CharmBase):
     """Charm the service."""
 
@@ -63,30 +63,39 @@ class CharmCinderThreeParCharm(CharmBase):
         return self.framework.model.get_relation(rel_name).units
 
     def _on_install(self, _):
-        self.unit.status = ops.model.MaintenanceStatus(
+        self.unit.status = MaintenanceStatus(
             "Installing packages")
         apt_install(['python3-3parclient'])
         try:
-            apt_purge(['python3-certifi', 'python3-urllib3', 'python3-requests'])
+            apt_purge(['python3-certifi',
+                       'python3-urllib3',
+                       'python3-requests'])
         except Exception as e:
-            logger.debug("Tried removing packages on install and failed with {}, ignoring".format(str(e)))
-        self.unit.status = ops.model.ActiveStatus("Unit is ready")
+            logger.debug("Tried removing packages on install and failed "
+                         "with {}, ignoring".format(str(e)))
+        self.unit.status = ActiveStatus("Unit is ready")
 
     def _on_config_changed_or_upgrade(self, event):
         svc_name = self.framework.model.app.name
         charm_config = self.framework.model.config
         r = self.framework.model.relations.get('storage-backend')[0]
         for u in self._rel_get_remote_units('storage-backend'):
-            r.data[self.unit]['backend_name'] = charm_config['volume-backend-name'] or svc_name
-            r.data[self.unit]['subordinate_configuration'] = json.dumps(CinderThreeParContext(charm_config, svc_name))
+            r.data[self.unit]['backend_name'] = \
+                charm_config['volume-backend-name'] or svc_name
+            r.data[self.unit]['subordinate_configuration'] = \
+                json.dumps(CinderThreeParContext(charm_config, svc_name))
 
     def _on_render_storage_backend(self, event):
         svc_name = self.framework.model.app.name
         charm_config = self.framework.model.config
-        data = self.framework.model.relations.get(event.relation.name)[0].data
+#        relations = self.framework.model.relations
+#        data = relations.get(event.relation.name)[0].data
         data = event.relation.data
-        data[self.unit]['backend_name'] = charm_config['volume-backend-name'] or svc_name
-        data[self.unit]['subordinate_configuration'] = json.dumps(CinderThreeParContext(charm_config, svc_name))
+        data[self.unit]['backend_name'] = \
+            charm_config['volume-backend-name'] or svc_name
+        data[self.unit]['subordinate_configuration'] = \
+            json.dumps(CinderThreeParContext(charm_config, svc_name))
+
 
 if __name__ == "__main__":
     main(CharmCinderThreeParCharm)

tests/test_charm.py

@@ -2,13 +2,12 @@
 # See LICENSE file for licensing details.
 
 import unittest
-from unittest.mock import Mock
 
-import ops.model
-import ops.testing
-from charm import CharmCinderThreeParCharm
+from ops.model import Relation
+from ops.testing import Harness
+from src.charm import CharmCinderThreeParCharm
 
-TEST_3PAR_CINDER_BACKEND = '\
+TEST_3PAR_CONFIG = '\
 {"cinder": \
 {"/etc/cinder/cinder.conf": \
 {"sections": \
@@ -21,15 +20,18 @@ TEST_3PAR_CINDER_BACKEND = '\
 ["hpe3par_api_url", "test.url"], \
 ["hpe3par_cpg", ""], \
 ["volume-backend-name", "charm-cinder-three-par"], \
-["volume_driver", "cinder.volume.drivers.hpe.hpe_3par_fc.HPE3PARFCDriver"]]}}}}'
+["volume_driver", \
+"cinder.volume.drivers.hpe.hpe_3par_fc.HPE3PARFCDriver"]]}}}}'
+
 
 class TestCharm(unittest.TestCase):
     def setUp(self):
-        self.harness = ops.testing.Harness(CharmCinderThreeParCharm)
+        self.harness = Harness(CharmCinderThreeParCharm)
         self.addCleanup(self.harness.cleanup)
         self.harness.begin()
         self.model = self.harness.model
-        self.storage_backend = self.harness.add_relation('storage-backend', 'cinder')
+        self.storage_backend = \
+            self.harness.add_relation('storage-backend', 'cinder')
         self.harness.add_relation_unit(self.storage_backend, 'cinder/0')
 
     def test_config_changed(self):
@@ -40,6 +42,7 @@ class TestCharm(unittest.TestCase):
           "hpe3par-api-url": "test.url"
         })
         rel = self.model.get_relation('storage-backend', 0)
-        self.assertIsInstance(rel, ops.model.Relation)
-        self.assertEqual(rel.data[self.model.unit], {'backend_name': 'charm-cinder-three-par', 'subordinate_configuration': TEST_3PAR_CINDER_BACKEND})
-
+        self.assertIsInstance(rel, Relation)
+        self.assertEqual(rel.data[self.model.unit],
+                         {'backend_name': 'charm-cinder-three-par',
+                          'subordinate_configuration': TEST_3PAR_CONFIG})