tried it with axios

server/middleware/login.ts

@@ -0,0 +1,17 @@
+let globalUserObject: { [key: string]: any } | null = null;
+// let globalUserObject = null;
+
+export default defineEventHandler((event) => {
+
+    if (event.path.startsWith("/api/login")) {
+
+        // get user object from backend
+        const userObject = {
+            username: "test",
+            password: "asd"
+        }
+        globalUserObject = userObject;
+    }
+})
+
+export { globalUserObject };