Refactoring the backend

backend/src/middleware/cors.ts

@@ -0,0 +1,15 @@
+import { Request, Response, NextFunction } from "express";
+
+export const cors = () => {
+  return (req: Request, res: Response, next: NextFunction) => {
+    res.header("Access-Control-Allow-Origin", "*");
+    res.header("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS");
+    res.header("Access-Control-Allow-Headers", "Content-Type, Authorization, Cookie");
+    res.header("Access-Control-Allow-Credentials", "true");
+
+    if (req.method === "OPTIONS") {
+      return res.sendStatus(200);
+    }
+    next();
+  };
+};