cloudflare worker - strip referral query parameters such as fbclid

stripParamsWorker.js

/**
 * Define regular expressions at top to have them precompiled.
 */
const urlRegex = new RegExp('^(refreshce|gclid|cx|ie|cof|siteurl|zanpid|origin|utm_[a-z]+|fbid|fbclid|mr:[A-z]+|ref(id|src))$');

addEventListener('fetch', event => {
    event.passThroughOnException()
    event.respondWith(handleRequest(event.request))
})
  
  
async function handleRequest(request) {
    
    let url = new URL(request.url)
    
    url = await normalizeUrl(url)
    
    let modifiedRequest = new Request(url, request)
  
    return fetch(modifiedRequest)
}

async function normalizeUrl(url) {
    let deleteKeys = []
    
    for(var key of url.searchParams.keys()) { 
        if(key.match(urlRegex)){
            deleteKeys.push(key)
        }
    }

    deleteKeys.map(k => url.searchParams.delete(k))

    return url
}