Merge lp:~james-page/charm-helpers/os-application-version into lp:charm-helpers

[James Page]

Add basic helper to set OpenStack application version

Juju 2.0 supports setting of the version of the application that is
deployed; add an openstack centric helper which will set version based on:

a) The provided package, if installed - e.g. 13.1.1
b) Using os_release to determing the codename of the install e.g. newton

This is designed to be called after every hook execution, including assess
status so that if the package version changes outside of charm lifecycle
events, this is also detected and the juju application version is updated.

[Liam Young (gnuoy)]

Please consider using fetch.apt_cache it has some extra smarts. fwiw its what get_os_codename_package etc uses

review: Needs Fixing

[Liam Young (gnuoy)]

oh, doh. you are

review: Approve

=== modified file 'charmhelpers/contrib/openstack/utils.py'
--- charmhelpers/contrib/openstack/utils.py	2016-07-20 15:44:32 +0000
+++ charmhelpers/contrib/openstack/utils.py	2016-09-16 09:56:30 +0000
@@ -51,7 +51,8 @@
     relation_set,
     service_name,
     status_set,
-    hook_name
+    hook_name,
+    application_version_set,
 )
 
 from charmhelpers.contrib.storage.linux.lvm import (
@@ -1889,3 +1890,29 @@
         flags[key.strip(post_strippers)] = value.rstrip(post_strippers)
 
     return flags
+
+
+def os_application_version_set(package):
+    '''Set version of application for Juju 2.0 and later'''
+    import apt_pkg as apt
+    cache = apt_cache()
+    application_version = None
+    application_codename = os_release(package)
+
+    try:
+        pkg = cache[package]
+        if not pkg.current_ver:
+            juju_log('Package {} is not currently installed.'.format(package),
+                     DEBUG)
+        else:
+            application_version = apt.upstream_version(pkg.current_ver.ver_str)
+    except:
+        juju_log('Package {} has no installation candidate.'.format(package),
+                 DEBUG)
+
+    # NOTE(jamespage) if not able to figure out package version, fallback to
+    #                 openstack codename version detection.
+    if not application_version:
+        application_version_set(application_codename)
+    else:
+        application_version_set(application_version)

=== modified file 'tests/contrib/openstack/test_openstack_utils.py'
--- tests/contrib/openstack/test_openstack_utils.py	2016-07-12 19:54:24 +0000
+++ tests/contrib/openstack/test_openstack_utils.py	2016-09-16 09:56:30 +0000
@@ -1788,5 +1788,19 @@
         self.assertTrue(action_set.called)
         self.assertTrue(traceback.called)
 
+    @patch.object(openstack, 'os_release')
+    @patch.object(openstack, 'application_version_set')
+    def test_os_application_version_set(self,
+                                        mock_application_version_set,
+                                        mock_os_release):
+        with patch('apt_pkg.Cache') as cache:
+            cache.return_value = self._apt_cache()
+            mock_os_release.return_value = 'mitaka'
+            openstack.os_application_version_set('neutron-common')
+            mock_application_version_set.assert_called_with('7.0.1')
+            openstack.os_application_version_set('cinder-common')
+            mock_application_version_set.assert_called_with('mitaka')
+
+
 if __name__ == '__main__':
     unittest.main()