Closes #19633

conditions.py - Change condition with self.negate to result XOR self.negate for compactness.
context_managers.py added context manager suppress_event_exp to prevent missing exceptions in cycles related to sequential event handling
events.py - using cm suppress_event_exp.
test_event_rules.py - added test to emulate the exception in process_event_function and verify that exception was logged properly.

netbox/extras/conditions.py

@@ -80,16 +80,15 @@ class Condition:
         except TypeError:
             # Invalid key path
             value = None
+
         if value is None:
             # Handle comparison case when value is None.
             if self.op in (self.GT, self.GTE, self.LT, self.LTE, self.IN, self.CONTAINS, self.REGEX):
-                result = False
-        else:
-            result = self.eval_func(value)
+                return False ^ self.negate
 
-        if self.negate:
-            return not result
-        return result
+        result = self.eval_func(value)
+
+        return result ^ self.negate
 
     # Equivalency
 

netbox/extras/events.py

@@ -11,6 +11,7 @@ from django_rq import get_queue
 from core.events import *
 from netbox.config import get_config
 from netbox.constants import RQ_QUEUE_DEFAULT
+from netbox.context_managers import suppress_event_exp
 from netbox.registry import registry
 from users.models import User
 from utilities.api import get_serializer_for_model
@@ -86,71 +87,73 @@ def process_event_rules(event_rules, object_type, event_type, data, username=Non
 
     for event_rule in event_rules:
 
-        # Evaluate event rule conditions (if any)
-        if not event_rule.eval_conditions(data):
-            continue
+        with suppress_event_exp(logger):
 
-        # Compile event data
-        event_data = event_rule.action_data or {}
-        event_data.update(data)
+            # Evaluate event rule conditions (if any)
+            if not event_rule.eval_conditions(data):
+                continue
 
-        # Webhooks
-        if event_rule.action_type == EventRuleActionChoices.WEBHOOK:
+            # Compile event data
+            event_data = event_rule.action_data or {}
+            event_data.update(data)
 
-            # Select the appropriate RQ queue
-            queue_name = get_config().QUEUE_MAPPINGS.get('webhook', RQ_QUEUE_DEFAULT)
-            rq_queue = get_queue(queue_name)
+            # Webhooks
+            if event_rule.action_type == EventRuleActionChoices.WEBHOOK:
 
-            # Compile the task parameters
-            params = {
-                "event_rule": event_rule,
-                "model_name": object_type.model,
-                "event_type": event_type,
-                "data": event_data,
-                "snapshots": snapshots,
-                "timestamp": timezone.now().isoformat(),
-                "username": username,
-                "retry": get_rq_retry()
-            }
-            if snapshots:
-                params["snapshots"] = snapshots
-            if request_id:
-                params["request_id"] = request_id
+                # Select the appropriate RQ queue
+                queue_name = get_config().QUEUE_MAPPINGS.get('webhook', RQ_QUEUE_DEFAULT)
+                rq_queue = get_queue(queue_name)
 
-            # Enqueue the task
-            rq_queue.enqueue(
-                "extras.webhooks.send_webhook",
-                **params
-            )
+                # Compile the task parameters
+                params = {
+                    "event_rule": event_rule,
+                    "model_name": object_type.model,
+                    "event_type": event_type,
+                    "data": event_data,
+                    "snapshots": snapshots,
+                    "timestamp": timezone.now().isoformat(),
+                    "username": username,
+                    "retry": get_rq_retry()
+                }
+                if snapshots:
+                    params["snapshots"] = snapshots
+                if request_id:
+                    params["request_id"] = request_id
 
-        # Scripts
-        elif event_rule.action_type == EventRuleActionChoices.SCRIPT:
-            # Resolve the script from action parameters
-            script = event_rule.action_object.python_class()
+                # Enqueue the task
+                rq_queue.enqueue(
+                    "extras.webhooks.send_webhook",
+                    **params
+                )
 
-            # Enqueue a Job to record the script's execution
-            from extras.jobs import ScriptJob
-            ScriptJob.enqueue(
-                instance=event_rule.action_object,
-                name=script.name,
-                user=user,
-                data=event_data
-            )
+            # Scripts
+            elif event_rule.action_type == EventRuleActionChoices.SCRIPT:
+                # Resolve the script from action parameters
+                script = event_rule.action_object.python_class()
 
-        # Notification groups
-        elif event_rule.action_type == EventRuleActionChoices.NOTIFICATION:
-            # Bulk-create notifications for all members of the notification group
-            event_rule.action_object.notify(
-                object_type=object_type,
-                object_id=event_data['id'],
-                object_repr=event_data.get('display'),
-                event_type=event_type
-            )
+                # Enqueue a Job to record the script's execution
+                from extras.jobs import ScriptJob
+                ScriptJob.enqueue(
+                    instance=event_rule.action_object,
+                    name=script.name,
+                    user=user,
+                    data=event_data
+                )
 
-        else:
-            raise ValueError(_("Unknown action type for an event rule: {action_type}").format(
-                action_type=event_rule.action_type
-            ))
+            # Notification groups
+            elif event_rule.action_type == EventRuleActionChoices.NOTIFICATION:
+                # Bulk-create notifications for all members of the notification group
+                event_rule.action_object.notify(
+                    object_type=object_type,
+                    object_id=event_data['id'],
+                    object_repr=event_data.get('display'),
+                    event_type=event_type
+                )
+
+            else:
+                raise ValueError(_("Unknown action type for an event rule: {action_type}").format(
+                    action_type=event_rule.action_type
+                ))
 
 
 def process_event_queue(events):
@@ -160,27 +163,28 @@ def process_event_queue(events):
     events_cache = defaultdict(dict)
 
     for event in events:
-        event_type = event['event_type']
-        object_type = event['object_type']
+        with suppress_event_exp(logger):
+            event_type = event['event_type']
+            object_type = event['object_type']
 
-        # Cache applicable Event Rules
-        if object_type not in events_cache[event_type]:
-            events_cache[event_type][object_type] = EventRule.objects.filter(
-                event_types__contains=[event['event_type']],
-                object_types=object_type,
-                enabled=True
+            # Cache applicable Event Rules
+            if object_type not in events_cache[event_type]:
+                events_cache[event_type][object_type] = EventRule.objects.filter(
+                    event_types__contains=[event['event_type']],
+                    object_types=object_type,
+                    enabled=True
+                )
+            event_rules = events_cache[event_type][object_type]
+
+            process_event_rules(
+                event_rules=event_rules,
+                object_type=object_type,
+                event_type=event['event_type'],
+                data=event['data'],
+                username=event['username'],
+                snapshots=event['snapshots'],
+                request_id=event['request_id']
             )
-        event_rules = events_cache[event_type][object_type]
-
-        process_event_rules(
-            event_rules=event_rules,
-            object_type=object_type,
-            event_type=event['event_type'],
-            data=event['data'],
-            username=event['username'],
-            snapshots=event['snapshots'],
-            request_id=event['request_id']
-        )
 
 
 def flush_events(events):

netbox/extras/tests/test_event_rules.py

@@ -390,6 +390,70 @@ class EventRuleTest(APITestCase):
         with patch.object(Session, 'send', dummy_send):
             send_webhook(**job.kwargs)
 
+    def test_suppression_flush_events(self):
+
+        # Use context manager to verify that exception was logged as we expected
+        with self.assertLogs('netbox.events_processor', level='ERROR') as cm:
+
+            # Get the known event
+            event = EventRule.objects.get(name='Event Rule 2')
+
+            site = Site.objects.create(name='Site 1', slug='site-1', status=SiteStatusChoices.STATUS_PLANNED)
+
+            # Update an object via the REST API
+            data = {
+                'name': 'Site X',
+                'status': SiteStatusChoices.STATUS_ACTIVE,
+            }
+            url = reverse('dcim-api:site-detail', kwargs={'pk': site.pk})
+            self.add_permissions('dcim.change_site')
+            response = self.client.patch(url, data, format='json', **self.header)
+            self.assertHttpStatus(response, status.HTTP_200_OK)
+
+            # Verify that a background task was queued for the updated object
+            self.assertEqual(self.queue.count, 1)
+            job = self.queue.jobs[0]
+            self.assertEqual(job.kwargs['event_rule'], event)
+            self.assertEqual(job.kwargs['event_type'], OBJECT_UPDATED)
+            self.assertEqual(job.kwargs['model_name'], 'site')
+            self.assertEqual(job.kwargs['data']['id'], site.pk)
+            self.assertEqual(job.kwargs['data']['status']['value'], SiteStatusChoices.STATUS_ACTIVE)
+            self.assertEqual(job.kwargs['snapshots']['prechange']['name'], 'Site 1')
+            self.assertEqual(job.kwargs['snapshots']['prechange']['status'], SiteStatusChoices.STATUS_PLANNED)
+            self.assertEqual(job.kwargs['snapshots']['postchange']['name'], 'Site X')
+            self.assertEqual(job.kwargs['snapshots']['postchange']['status'], SiteStatusChoices.STATUS_ACTIVE)
+
+            # Update the event with non-existent
+            event.action_type = 'non-existent-action-type'
+            event.save()
+
+            # Cleanup queue
+            self.queue.empty()
+
+            # Verify that a queue is empty
+            self.assertEqual(self.queue.count, 0)
+
+            # Update an object via the REST API
+            data = {
+                'name': 'Site X',
+                'status': SiteStatusChoices.STATUS_PLANNED,
+            }
+            url = reverse('dcim-api:site-detail', kwargs={'pk': site.pk})
+            self.add_permissions('dcim.change_site')
+            response = self.client.patch(url, data, format='json', **self.header)
+            self.assertHttpStatus(response, status.HTTP_200_OK)
+
+            # Verify that a queue is still empty
+            self.assertEqual(self.queue.count, 0)
+
+        # Verify that we have only one ERROR message in our log
+        self.assertEqual(len(cm.output), 1)
+
+        # Verify message format
+        pattern = (r"Error ValueError in ValueError at .*? - Unknown action type for"
+                   r" an event rule: non-existent-action-type")
+        self.assertRegex(cm.output[0], pattern)
+
     def test_duplicate_triggers(self):
         """
         Test for erroneous duplicate event triggers resulting from saving an object multiple times

netbox/netbox/context_managers.py

@@ -1,8 +1,8 @@
+import traceback
 from contextlib import contextmanager
 
 from netbox.context import current_request, events_queue
 from netbox.utils import register_request_processor
-from extras.events import flush_events
 
 
 @register_request_processor
@@ -14,6 +14,8 @@ def event_tracking(request):
 
     :param request: WSGIRequest object with a unique `id` set
     """
+    from extras.events import flush_events
+
     current_request.set(request)
     events_queue.set({})
 
@@ -26,3 +28,19 @@ def event_tracking(request):
     # Clear context vars
     current_request.set(None)
     events_queue.set({})
+
+
+@contextmanager
+def suppress_event_exp(logger=None):
+    """
+    Suppress exceptions that may occur during event handling.
+    """
+    try:
+        yield
+    except Exception as e:
+        if logger:
+            tb = e.__traceback__
+            last_frame = tb.tb_frame if tb else None
+            filename = last_frame.f_code.co_filename if last_frame else 'unknown'
+            lineno = tb.tb_lineno if tb else 0
+            logger.error(f"Error {e.__class__.__name__} in {e.__class__.__name__} at {filename}:{lineno} - {str(e)}")