Support unmarking notifications as read

src/api/notifications.py

@@ -103,6 +103,9 @@ async def read_notification(notification_id: PydanticObjectId, user: CurrentUser
     if cast(User, notification.user).id != user.id:
         raise HTTPException(status.HTTP_403_FORBIDDEN, "You can only access your own notifications.")
 
+    if notification.read:
+        raise HTTPException(status.HTTP_409_CONFLICT, "Notification is already marked as read.")
+
     notification.read = True
     notification.read_at = datetime.now(UTC)
     notification = await notification.replace()
@@ -110,6 +113,29 @@ async def read_notification(notification_id: PydanticObjectId, user: CurrentUser
     return NotificationData.from_notification(notification)
 
 
+@notifications_router.post("/{notification_id}/unread")
+async def unread_notification(notification_id: PydanticObjectId, user: CurrentUserDep) -> NotificationData:
+    """Mark a notification as unread."""
+    notification = await Notification.get(notification_id, fetch_links=True)
+
+    if notification is None:
+        raise HTTPException(status.HTTP_404_NOT_FOUND, "Notification not found.")
+
+    if user.id is None:
+        raise MissingIdError(user)
+
+    if cast(User, notification.user).id != user.id:
+        raise HTTPException(status.HTTP_403_FORBIDDEN, "You can only access your own notifications.")
+
+    if not notification.read:
+        raise HTTPException(status.HTTP_409_CONFLICT, "Notification is already marked as unread.")
+
+    notification.read = False
+    notification.read_at = None
+    notification = await notification.replace()
+    return NotificationData.from_notification(notification)
+
+
 router = APIRouter()
 router.include_router(base_router)
 router.include_router(notifications_router)