Cloudflare worker script to rewrite requests to lowercase, to prevent duplicate page URLs

cloudflare-worker-force-lowercase.js

addEventListener('fetch', event => {
  event.respondWith(handleRequest(event.request))
})

/**
 * Fetch and log a request
 * @param {Request} request
 */
async function handleRequest(request) {
  let url = request.url
  // console.log('New url: ', url.toLowerCase())
  console.log('Got request', request.url)
  
  if (url.toLowerCase() !== request.url) {
    return new Response('', { status: 301, headers: { 'Location': url.toLowerCase() } });
  } else {
    let response = await fetch(request)
    console.log('Got response', response.url)
    return response
  }
}