improvement: block open another ticket from same contact when already a open / pending ticket

backend/src/helpers/CheckContactOpenTickets.ts

@@ -0,0 +1,17 @@
+import { Op } from "sequelize";
+import AppError from "../errors/AppError";
+import Ticket from "../models/Ticket";
+
+const CheckContactOpenTickets = async (contactId: number): Promise<void> => {
+  const ticket = await Ticket.findOne({
+    where: { contactId, status: { [Op.or]: ["open", "pending"] } }
+  });
+
+  if (ticket) {
+    throw new AppError(
+      "There's already an open or pending ticket for this contact."
+    );
+  }
+};
+
+export default CheckContactOpenTickets;