Request Cookie Store

An implementation of the Cookie Store API for request handlers.

It uses the Cookie header of a request to populate the store and keeps a record of changes that can be exported as a list of Set-Cookie headers.

It is intended as a cookie middleware for Cloudflare Workers or other Worker Runtimes, but perhaps there are other uses as well. It is best combined with Signed Cookie Store or Encrypted Cookie Store.

Recipes

The following snippets should convey how this is intended to be used. Aso see the interface for more usage options.

Creating a New Store

import { RequestCookieStore } from '@worker-tools/request-cookie-store';

// Creating a request on the fly. Typically it will be provided by CF Workers, etc.
const request = new Request('/', { headers: { 'cookie': 'foo=bar; fizz=buzz' } });

const cookieStore = new RequestCookieStore(request);

We can now access cookie values from the store like so:

const value = (await cookieStore.get(name))?.value;

This is a bit verbose, so we'll make it more ergonomic in the next step.

Fast Read Access

To avoid using await for every read, we can parse all cookies into a Map once:

type Cookies = ReadonlyMap<string, string>;

const all = await cookieStore.getAll();

new Map(all.map(({ name, value }) => [name, value])) as Cookies;
// => Map { "foo" => "bar", "fizz" => "buzz" }

Exporting Headers

Use set on the cookie store to add cookies and include them in a response.

await cookieStore.set('foo', 'buzz');
await cookieStore.set('fizz', 'bar');

event.respondWith(new Response(null, cookieStore));

Will produce the following HTTP headers in Worker Runtimes that support multiple Set-Cookie headers:

HTTP/1.1 200 OK
content-length: 0
set-cookie: foo=buzz
set-cookie: fizz=bar

Combine With Other Headers

The above example above uses the fact that the cookie store will correctly destructure the headers key. To add additional headers to a response, you can do the following:

const response = new Response('{}', {
  headers: [
    ['content-type': 'application/json'],
    ...cookieStore.headers,
  ],
});

Disclaimers

This is not a polyfill! It is intended as a cookie middleware for Cloudflare Workers or other Worker Runtimes!

Due to the weirdness of the Fetch API Headers class w.r.t Set-Cookie (or rather, the lack of special treatment), it is not likely to work in a Service Worker.

Worker Tools are a collection of TypeScript libraries for writing web servers in Worker Runtimes such as Cloudflare Workers, Deno Deploy and Service Workers in the browser.

If you liked this module, you might also like:

• 🧭 Worker Router --- Complete routing solution that works across CF Workers, Deno and Service Workers
• 🔋 Worker Middleware --- A suite of standalone HTTP server-side middleware with TypeScript support
• 📄 Worker HTML --- HTML templating and streaming response library
• 📦 Storage Area --- Key-value store abstraction across Cloudflare KV, Deno and browsers.
• 🆗 Response Creators --- Factory functions for responses with pre-filled status and status text
• 🎏 Stream Response --- Use async generators to build streaming responses for SSE, etc...
• 🥏 JSON Fetch --- Drop-in replacements for Fetch API classes with first class support for JSON.
• 🦑 JSON Stream --- Streaming JSON parser/stingifier with first class support for web streams.

Worker Tools also includes a number of polyfills that help bridge the gap between Worker Runtimes:

• ✏️ HTML Rewriter --- Cloudflare's HTML Rewriter for use in Deno, browsers, etc...
• 📍 Location Polyfill --- A Location polyfill for Cloudflare Workers.
• 🦕 Deno Fetch Event Adapter --- Dispatches global fetch events using Deno’s native HTTP server.

Fore more visit workers.tools.