feat(notification): add single worker handling for notification deduplication

- Introduced a check in claim_notification_slot to allow notifications when only one worker is active.
- Updated tests to verify that deduplication does not occur when the worker count is set to one.

Author: x0sina

app/notification/dedup.py

@@ -10,6 +10,7 @@
 from app.nats import is_nats_enabled
 from app.nats.kv_cas import kv_cas_json, kv_get_json
 from app.utils.logger import get_logger
+from config import server_settings
 
 logger = get_logger("Notification")
 
@@ -48,6 +49,9 @@ def _identity(value: Any) -> str:
 
 async def claim_notification_slot(event_name: str, args: tuple[Any, ...], kwargs: dict[str, Any]) -> bool:
     """Return True if this worker should emit the notification."""
+    if server_settings.workers <= 1:
+        return True
+
     key = notification_fingerprint(event_name, args, kwargs)
     now = time.time()
     async with _local_lock:

tests/test_notification_dedup.py

@@ -10,11 +10,21 @@
 def _reset_notification_dedup(monkeypatch: pytest.MonkeyPatch):
     notification_dedup._local_claims.clear()
     notification_dedup._kv = None
+    monkeypatch.setattr(notification_dedup.server_settings, "workers", 4)
     monkeypatch.setattr(notification_dedup, "is_nats_enabled", lambda: False)
     yield
     notification_dedup._local_claims.clear()
 
 
+@pytest.mark.asyncio
+async def test_single_worker_does_not_dedup(monkeypatch: pytest.MonkeyPatch):
+    monkeypatch.setattr(notification_dedup.server_settings, "workers", 1)
+    monkeypatch.setattr(notification_dedup, "_claim_shared", AsyncMock(side_effect=AssertionError("dedup must not run")))
+    node = NodeNotification(id=3, name="Hetz Tunnel", node_version="0.5.4", xray_version="26.3.27")
+    assert await notification_dedup.claim_notification_slot("connect_node", (node,), {}) is True
+    assert await notification_dedup.claim_notification_slot("connect_node", (node,), {}) is True
+
+
 @pytest.mark.asyncio
 async def test_claim_notification_slot_drops_same_event_twice():
     node = NodeNotification(id=3, name="Hetz Tunnel", node_version="0.5.4", xray_version="26.3.27")