Cloudflare Workers

Cloud Auth is fully compatible with Cloudflare Workers and can verify requests like this.

Verifier

An authenticateRequest function that validates an incoming web standard request can be implemented in src/authenticate.ts like this:

import { createVerifier } from '@featherscloud/auth'

const appId = '<your-app-id>'
const verifier = createVerifier({ appId })

/**
 * Verify authentication for a web standard request object.
 * Will throw an error if verification was not successful.
 * 
 * @param request The request object
 * @returns The authentication information like `user` and `token`
 */
export async function authenticateRequest(request: Request) {
  const header = request.headers.get('Authorization')

  return verifier.verifyHeader(header!)
}

Worker

It can then be used in a Cloudflare worker like this:

import { authenticateRequest } from './authenticate'

// Headers for handling CORS
const headers = {
  'Content-Type': 'application/json',
  'Access-Control-Allow-Headers': '*',
  'Access-Control-Allow-Methods': 'GET',
  'Access-Control-Allow-Origin': '*',
}

export default {
  async fetch(request, _env, _ctx): Promise<Response> {
    // Get the path from the request object
    const url = new URL(request.url);
    const path = url.pathname;

    try {
      // Handle CORS preflight request
      if (request.method === 'OPTIONS') {
        return new Response(null, {
          status: 200,
          headers,
        })
      } else if (path === '/message') {
        const { user } = await authenticateRequest(request)

        if (!user) {
          throw new Error('Cloud auth user not found')
        }
  
        const body = {
          message: `Hello ${user.email} from Cloudflare Worker!`,
        }
  
        return Response.json(body, {
          status: 200,
          headers,
        })
      } else {
        throw new Error(`Not found ${path}`)
      }
    }
    catch (error) {
      return Response.json({ error: (error as any).message }, {
        status: 400,
        headers,
      })
    }
  },
} satisfies ExportedHandler<Env>

The full Cloudflare Worker example can be found here.