Merge "Fix broken v4 caching due to leader-get asymmetry"

osci.yaml

@@ -22,7 +22,7 @@
       needs_charm_build: true
       charm_build_name: vault
       build_type: charmcraft
-      charmcraft_channel: 2.x/edge
+      charmcraft_channel: latest/edge
 
 - job:
     name: jammy-mysql8

src/lib/charm/vault_pki.py

@@ -598,7 +598,14 @@ class CertCache:
         """
         value = hookenv.leader_get(key)
         if value:
-            return json.loads(value)
+            if key is not None:
+                # load the value that was json serialised in _store()
+                return json.loads(value)
+            else:
+                # due to a weird asymetry been leader_set and leader_get,
+                # leader_get() already deserialises as json so if no key was
+                # specified, it's already been deserialised.
+                return value
         return ""
 
     @staticmethod

unit_tests/test_lib_charm_vault_pki.py

@@ -800,6 +800,21 @@ class TestLibCharmVaultPKI(unit_tests.test_utils.CharmTestCase):
         self.assertEqual(vault_pki.CertCache(request)._fetch("mine"),
                          'the-value')
 
+    @patch.object(vault_pki.hookenv, 'leader_get')
+    def test_certcache__fetch_none(self, mock_leader_get):
+        request = self._default_request()
+        # due to weird asymetry between leader_get and leader_set, if no
+        # attribute is passed to leader_get() then the result is the
+        # deserialised set of key, values as a dictionary.
+        leader_get = {
+            'a': 'an-a',
+            'b': 'an-b',
+        }
+
+        mock_leader_get.return_value = leader_get
+        self.assertEqual(vault_pki.CertCache(request)._fetch(None), leader_get)
+        mock_leader_get.assert_called_once_with(None)
+
     @patch.object(vault_pki.hookenv, 'leader_set')
     def test_certcache__store(self, mock_leader_set):
         request = self._default_request()