@columenlabs/lumen-auth

Lumen's sign-in checks for Workers behind Cloudflare Access: verify the token Access signs on every request, in the Worker, so a route stays closed even when the Access application is misconfigured or a request reached the Worker another way. No dependencies: Web Crypto and fetch, so it runs in a Worker, Bun or Node.

• Docs: https://lumen.columenlabs.com/docs/
• For agents: https://lumen.columenlabs.com/llms.txt
• Source: https://github.com/columenlabs/lumen (packages/auth). MIT.

Install

bun add @columenlabs/lumen-auth

Pin it to the same exact version as the other Lumen packages.

Verify an Access token

import { AccessVerifier, accessToken } from '@columenlabs/lumen-auth';

// One per isolate: the team's signing keys are fetched once and kept an hour.
const access = new AccessVerifier({
  teamDomain: 'myteam.cloudflareaccess.com',
  aud: [env.ACCESS_AUD],            // one application's AUD tag, or several (one Worker, several hosts)
});

const who = await access.verify(accessToken(request));
if (!who) return new Response('Not found', { status: 404 });
who.email;         // the person, when a person signed in
who.serviceToken;  // the service token's client ID, when a service token signed in
who.sub;           // Access's subject id

verify returns null for a missing, malformed, expired or wrongly signed token, a token for another application (aud) or another team (iss). Only RS256 is accepted. A key id it has not seen fetches the keys again.

| Export | | |---|---| | AccessVerifier(config, fetch?, now?) | verify(token) → AccessIdentity or null. fetch and now are for tests | | AccessConfig | { teamDomain, aud } | | AccessIdentity | { sub, email?, serviceToken? } | | accessToken(request) | The request's Cf-Access-Jwt-Assertion, if any | | ACCESS_HEADER | 'cf-access-jwt-assertion' |

Who Access lets in stays Access's policy; what each person may do stays the app's own. This package only proves the request came through Access.

Versions

0.x: any minor may break things until 1.0. Every merge to Lumen's main publishes the next patch of every Lumen package; see the releases.