lots of cleanup, fixed relation handling, etc

src/layer.yaml

@@ -1,2 +1,5 @@
 includes:
   - 'layer:openstack'
+  - 'interface:cinder-backend'
+
+repo: https://github.com/mskalka/charm-cinder-purestorage

src/lib/charm/openstack/cinder_purestorage.py

@@ -1,4 +1,5 @@
 import json
+import subprocess
 
 from charmhelpers.core.hookenv import (
     config,
@@ -23,20 +24,13 @@ class PureStorageCharm(OpenStackCharm):
     packages = ['']
     release = 'queens'
 
-    def set_relation_data(self):
+    def install(self):
-        rel_id = relation_ids('storage-backend')
+        subprocess.check_call(['pip', 'install', 'purestorage', '--no-deps'])
-        if not len(rel_id):
+
-            log("No 'storage-backend' relation detected, skipping.")
+    def get_purestorage_config(self):
-        else:
-            relation_set(
-                relation_id=rel_id[0],
-                backend_name=config('volume-backend-name') or service_name(),
-                subordinate_configuration=json.dumps(
-                    PureStorageSubordinateContext()()),
-                stateless=True,
-            )
-            log('Relation data set for {}'.format(rel_id[0]))
         status_set('active', 'Unit is ready')
+        name = config('volume-backend-name') or service_name()
+        return name, PureStorageSubordinateContext()()
 
 
 class PureStorageSubordinateContext(OSContextGenerator):
@@ -61,16 +55,12 @@ class PureStorageSubordinateContext(OSContextGenerator):
             raise ProtocolNotImplimented(
                 config('protocol'), ' is not an implimented protocol  driver, '
                 'please choose between `iscsi` and `fc`.')
-
+        return {
-        for rid in relation_ids(self.interfaces[0]):
+            "cinder": {
-            log('Setting relation data for {}'.format(rid))
+                "/etc/cinder/cinder.conf": {
-            self.related = True
+                    "sections": {
-            return {
+                        service: ctxt
-                "cinder": {
-                    "/etc/cinder/cinder.conf": {
-                        "sections": {
-                            service: ctxt
-                        }
                     }
                 }
             }
+        }

src/reactive/cinder_purestorage_handlers.py

@@ -5,20 +5,22 @@ import charms.reactive as reactive
 import charm.openstack.cinder_purestorage as cinder_pure
 assert cinder_pure
 
-charm.use_defaults('charm.installed')
 
-
+@reactive.when_any('install')
-@reactive.when_any('storage-backend.joined', 'storage-backend.changed')
+def install_pure_driver():
-@reactive.when_not('storage-backend.available')
-def storage_backend():
     with charm.provide_charm_instance() as charm_class:
-        charm_class.set_relation_data()
+        charm_class.install()
-    reactive.set_state('storage-backend.available')
 
 
-@reactive.when('config.changed')
+@reactive.when('storage-backend.available')
+@reactive.when_not('cinder.configured')
+def storage_backend(principle):
+    with charm.provide_charm_instance() as charm_class:
+        name, config = charm_class.get_purestorage_config()
+        principle.configure_principal(name, config)
+    reactive.set_state('cinder.configured')
+
+
+@reactive.hook('config-changed')
 def update_config():
-    reactive.remove_state('storage-backend.available')
+    reactive.remove_state('cinder.configured')
-    with charm.provide_charm_instance() as charm_class:
-        charm_class.set_relation_data()
-    reactive.set_state('storage-backend.available')