Fix notify filter when data item is None

When data[k] is None during match check, we are getting annoying
TypeError exceptions like: "TypeError: expected string or buffer".
This patch adds a check that data[k] is something the regex can do
matching.

Change-Id: I75c8f602a59a90aeb5a6973f2e9e25708194ad78

oslo_messaging/notify/filter.py

@@ -15,6 +15,8 @@
 
 import re
 
+import six
+
 
 class NotificationFilter(object):
 
@@ -31,7 +33,7 @@ class NotificationFilter(object):
     filter_rule =  NotificationFilter(
          publisher_id='^compute.*',
          context={'tenant_id': '^5f643cfc-664b-4c69-8000-ce2ed7b08216$',
-                  'roles='private'},
+                  'roles': 'private'},
          event_type='^compute\.instance\..*',
          metadata={'timestamp': 'Aug'},
          payload={'state': '^active$')
@@ -58,15 +60,27 @@ class NotificationFilter(object):
         return dict((k, re.compile(regex_list[k])) for k in regex_list)
 
     @staticmethod
-    def _check_for_mismatch(data, regex):
-        if isinstance(regex, dict):
-            for k in regex:
-                if (k not in data or not regex[k].match(data[k])):
+    def _check_for_single_mismatch(data, regex):
+        if regex is None:
+            return False
+        if not isinstance(data, six.string_types):
             return True
-        elif regex is not None and not regex.match(data):
+        if not regex.match(data):
             return True
         return False
 
+    @classmethod
+    def _check_for_mismatch(cls, data, regex):
+        if isinstance(regex, dict):
+            for k in regex:
+                if k not in data:
+                    return True
+                if cls._check_for_single_mismatch(data[k], regex[k]):
+                    return True
+            return False
+        else:
+            return cls._check_for_single_mismatch(data, regex)
+
     def match(self, context, publisher_id, event_type, metadata, payload):
         if (self._check_for_mismatch(publisher_id, self._regex_publisher_id) or
                 self._check_for_mismatch(event_type, self._regex_event_type) or

oslo_messaging/tests/notify/test_dispatcher.py

@@ -163,6 +163,13 @@ class TestDispatcherFilter(test_utils.BaseTestCase):
               event_type='instance.create.start',
               context={},
               match=False)),
+        # this is only for simulation
+        ('event_type_not_string',
+         dict(filter_rule=dict(event_type='^instance\.delete'),
+              publisher_id='compute01.manager',
+              event_type=['instance.swim', 'instance.fly'],
+              context={},
+              match=False)),
         ('context_match',
          dict(filter_rule=dict(context={'user': '^adm'}),
               publisher_id='compute01.manager',
@@ -206,6 +213,12 @@ class TestDispatcherFilter(test_utils.BaseTestCase):
               event_type='instance.create.start',
               context={},
               match=False)),
+        ('payload_value_none',
+         dict(filter_rule=dict(payload={'virtual_size': '2048'}),
+              publisher_id='compute01.manager',
+              event_type='instance.create.start',
+              context={},
+              match=False)),
         ('mix_match',
          dict(filter_rule=dict(event_type='^instance\.create',
                                publisher_id='^compute',
@@ -214,7 +227,6 @@ class TestDispatcherFilter(test_utils.BaseTestCase):
               event_type='instance.create.start',
               context={'user': 'admin'},
               match=True)),
-
     ]
 
     def test_filters(self):
@@ -224,7 +236,7 @@ class TestDispatcherFilter(test_utils.BaseTestCase):
 
         dispatcher = notify_dispatcher.NotificationDispatcher(
             [endpoint], serializer=None)
-        message = {'payload': {'state': 'active'},
+        message = {'payload': {'state': 'active', 'virtual_size': None},
                    'priority': 'info',
                    'publisher_id': self.publisher_id,
                    'event_type': self.event_type,