Cookie handling for fetch in Node.js - small CookieJar plugin for Luminara

[miller-28]

Hi everyone,

For anyone building on top of fetch in Node.js or server side environments and struggling with cookies, I released a small plugin that might help.

In the browser, cookies are handled for you.
On the server, if you use fetch (Node 18+ or undici), you need to:

• capture Set-Cookie headers
• store cookies in a jar
• send the correct Cookie header per request
• keep behavior consistent across retries, hedging, and multiple clients

I built luminara-cookie-jar, a CookieJar plugin for my HTTP client Luminara, to solve this in a clean way using tough-cookie.

Key points:

• automatic Set-Cookie capture on responses
• automatic Cookie injection on requests
• shared jars across multiple clients when needed
• full CookieJar API exposed via client.jar for advanced use
• integrates with retries, hedging, timeouts and stats in Luminara

Minimal example:

import { createLuminara } from "luminara";
import { cookieJarPlugin } from "luminara-cookie-jar";

const client = createLuminara({
  baseURL: "https://api.example.com",
  plugins: [cookieJarPlugin()]
});

// login - cookies stored automatically
await client.post("/login", { username: "user", password: "pass" });

// cookies are sent automatically on the next call
const profile = await client.get("/profile");

// direct access to the jar if needed
console.log(await client.jar.getCookies("https://api.example.com"));

Repo: https://github.com/miller-28/luminara-cookie-jar
npm: https://www.npmjs.com/package/luminara-cookie-jar

If you are using fetch on the server and need browser-like cookie behavior, this might be useful.