[zed] Ensure get_requests_for_local_unit doesn't fail on incomplete relation

This is a rebuild/make sync for charms to pickup the fix in charmhelpers to fix
any inadvertant accesses of ['ca'] in the relation data before it is available
from vault in the certificates relation.  Fix in charmhelpers is in [1].

[1] https://github.com/juju/charm-helpers/pull/826
Closes-Bug: #2028683

Change-Id: I1ef803d54c7f00e3293891fd3f0b9348c9246ba1

charmhelpers/contrib/openstack/cert_utils.py

@@ -414,18 +414,27 @@ def get_requests_for_local_unit(relation_name=None):
         is_legacy_request = set(sent).intersection(legacy_keys)
         for unit in related_units(rid):
             data = relation_get(rid=rid, unit=unit)
-            if data.get(raw_certs_key):
-                bundles.append({
-                    'ca': data['ca'],
-                    'chain': data.get('chain'),
-                    'certs': json.loads(data[raw_certs_key])})
-            elif is_legacy_request:
-                bundles.append({
-                    'ca': data['ca'],
-                    'chain': data.get('chain'),
-                    'certs': {sent['common_name']:
-                              {'cert': data.get(local_name + '.server.cert'),
-                               'key': data.get(local_name + '.server.key')}}})
+            # Note: Bug#2028683 - data may not be available if the certificates
+            # relation hasn't been populated by the providing charm. If no 'ca'
+            # in the data then don't attempt the bundle at all.
+            if data.get('ca'):
+                if data.get(raw_certs_key):
+                    bundles.append({
+                        'ca': data['ca'],
+                        'chain': data.get('chain'),
+                        'certs': json.loads(data[raw_certs_key])
+                    })
+                elif is_legacy_request:
+                    bundles.append({
+                        'ca': data['ca'],
+                        'chain': data.get('chain'),
+                        'certs': {
+                            sent['common_name']: {
+                                'cert': data.get(local_name + '.server.cert'),
+                                'key': data.get(local_name + '.server.key')
+                            }
+                        }
+                    })
 
     return bundles
 

tox.ini

@@ -65,6 +65,7 @@ deps = -r{toxinidir}/requirements.txt
 [testenv:pep8]
 basepython = python3
 deps = flake8==3.9.2
+       PyYAML==6.0.1
        git+https://github.com/juju/charm-tools.git
 commands = flake8 {posargs} hooks unit_tests tests actions lib files
            charm-proof