request-cookie-store.md

layout	description
page	An implementation of the Cookie Store API for request handlers.

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.

• Table of Contents {:toc .large-only}

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.

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Links: GitHub | ghuc.cc · NPM | Browse Package · deno.land | Docs {:.faded}