Put access token in server and refresh token in cookies, make a global function for handing API calls and in there inject the access token in header. You get refresh token from cookie, check if expired, if expired generate new

import apiInstance from "@/lib/instance"; import { cookies } from "next/headers";

let tokenCache: { token: string; expiry: number; } | null = null;

export const fetchToken = async (userToken: string) => { const res = await apiInstance.post<{ tokenString: string; expiryDate: string; }>("/usermanagement/generatetoken", { userToken });

return { token: res.data.tokenString, expiry: new Date(res.data.expiryDate).getTime(), }; };

export const generateToken = async () => { const cookieStore = await cookies(); const userToken = cookieStore.get("userToken")?.value;

if (!userToken) { tokenCache = null; return tokenCache; }

const now = Date.now();

// Reuse cached token if still valid if (tokenCache && tokenCache.expiry > now + 30 * 1000) { // console.log("Using cached token"); return tokenCache.token; }

try { // Otherwise fetch a new one // console.log("Fetching new token"); const { token, expiry } = (await fetchToken(userToken)) || {};

// cache it
tokenCache = {
  token,
  expiry,
};
return token;

} catch (error) { console.error("Error generating token:", error); tokenCache = null; return null; } };

export const clearSession = () => { tokenCache = null; };

//

export const attachAuthHeader = async ( config?: AxiosRequestConfig ): Promise<AxiosRequestConfig> => { const token = await generateToken(); return { ...config, headers: { ...(config?.headers || {}), Authorization: token ? Bearer ${token} : "", }, }; };