EvaluationContext.variables as AttrDict (#593)

policykit/policyengine/engine.py

@@ -11,6 +11,15 @@
 logger = logging.getLogger(__name__)
 db_logger = logging.getLogger("db")
 
+class AttrDict(dict):
+    """
+    For accessing variables using attribute-style access
+    e.g. variables.slack_channel_id
+    """
+    def __init__(self, *args, **kwargs):
+        super(AttrDict, self).__init__(*args, **kwargs)
+        self.__dict__ = self
+
 
 class EvaluationLogAdapter(logging.LoggerAdapter):
     def process(self, msg, kwargs):
@@ -50,7 +59,7 @@ def __init__(self, proposal):
             self.action = proposal.action
 
         self.policy = proposal.policy
-        self.variables = {}
+        self.variables = AttrDict()
         self.proposal = proposal
 
         # Can't use logger in filter step because proposal isn't saved yet
@@ -73,7 +82,7 @@ def __init__(self, proposal):
         self.metagov = Metagov(proposal)
 
         # Make policy variables available in the evaluation context
-        setattr(self, "variables", { v.name : v.value for v in self.policy.variables.all() or []})
+        setattr(self, "variables", AttrDict({ v.name : v.value for v in self.policy.variables.all() or []}))
 
 class PolicyEngineError(Exception):
     """Base class for exceptions raised from the policy engine"""