[core] Address SQLAlchemy deprecations

core/allnet.py

@@ -181,6 +181,11 @@ class AllnetServlet:
 
         if machine is not None:
             arcade = await self.data.arcade.get_arcade(machine["arcade"])
+
+            if arcade is None:
+                self.logger.error("The arcade %s belongs to (ID %s) does not exist!", req.serial, machine["arcade"])
+                return PlainTextResponse("stat=-3\n", status_code=500)
+
             if self.config.server.check_arcade_ip:
                 if arcade["ip"] and arcade["ip"] is not None and arcade["ip"] != req.ip:
                     msg = f"{req.serial} attempted allnet auth from bad IP {req.ip} (expected {arcade['ip']})."