Use helper in hooks as well

hooks/hooks.py

@@ -29,7 +29,8 @@ from charmhelpers.core.hookenv import (
 from charmhelpers.core.host import (
     service_restart,
     umount,
-    mkdir
+    mkdir,
+    cmp_pkgrevno
 )
 from charmhelpers.fetch import (
     apt_install,
@@ -50,7 +51,7 @@ hooks = Hooks()
 
 def install_upstart_scripts():
     # Only install upstart configurations for older versions
-    if ceph.get_ceph_version() < "0.55.1":
+    if cmp_pkgrevno('ceph', "0.55.1") < 0:
         for x in glob.glob('files/upstart/*.conf'):
             shutil.copy(x, '/etc/init/')
 
@@ -71,7 +72,7 @@ def emit_cephconf():
         'auth_supported': config('auth-supported'),
         'mon_hosts': ' '.join(get_mon_hosts()),
         'fsid': config('fsid'),
-        'version': ceph.get_ceph_version(),
+        'old_auth': cmp_pkgrevno('ceph', "0.51") < 0,
         'osd_journal_size': config('osd-journal-size'),
         'use_syslog': str(config('use-syslog')).lower()
     }

templates/ceph.conf

@@ -1,5 +1,5 @@
 [global]
-{% if version < "0.51" %}
+{% if old_auth %}
  auth supported = {{ auth_supported }}
 {% else %}
  auth cluster required = {{ auth_supported }}