Check for valid context in _priority_verify

stream_alert/alert_processor/outputs/pagerduty.py

@@ -347,6 +347,9 @@ def _priority_verify(self, context):
             dict: JSON object be used in the API call, containing the priority id
                   and the priority reference, empty if it fails or it does not exist
         """
+        if not context:
+            return dict()
+
         priority_name = context.get('incident_priority', False)
         if not priority_name:
             return dict()
@@ -442,9 +445,7 @@ def dispatch(self, **kwargs):
             rule_context = rule_context.get(self.__service__, {})
 
         # Use the priority provided in the context, use it or the incident will be low priority
-        incident_priority = {}
-        if rule_context:
-            incident_priority = self._priority_verify(rule_context)
+        incident_priority = self._priority_verify(rule_context)
 
         # Incident assignment goes in this order:
         #  Provided user -> provided policy -> default policy