Specifically, I'm trying to adapt this to a Pages Function. https://plausible.io/docs/proxy/guides/cloudflare

But maybe I don't need this listener?

Just now reading the docs for what passThroughOnException does, I don't think I do need it. It's fine for this function to fail closed.

the addEventListener('fetch') is for running code when the Worker is called. So yeah, you'd need to change this a little in order to make it work for Functions

I'll try without. Thanks, @User 🙂

something like this should work (untested):

js
const ScriptName = '/js/script.js';
const Endpoint = '/api/event';

const ScriptWithoutExtension = ScriptName.replace('.js', '');

export async function onRequest({ request, waitUntil }) {
  const pathname = new URL(request.url).pathname
  const [baseUri, ...extensions] = pathname.split('.')

  if (baseUri.endsWith(ScriptWithoutExtension)) {
      return getScript(request, waitUntil, extensions)
  } else if (pathname.endsWith(Endpoint)) {
      return postData(request)
  }
  return new Response(null, { status: 404 })
}

async function getScript(request, waitUntil, extensions) {
    let response = await caches.default.match(request);
    if (!response) {
        response = await fetch("https://plausible.io/js/plausible." + extensions.join("."));
        waitUntil(caches.default.put(request, response.clone()));
    }
    return response;
}

async function postData(req) {
    const request = new Request(req);
    request.headers.delete('cookie');
    return await fetch("https://plausible.io/api/event", request);
}

What is the proper way to invoke waitUntil in a Pages Function? I'm getting a

TypeError: Illegal invocation  at Object.waitUntil

error. It must be called from an

instanceof ExecutionContext

. These docs suggest that

context.waitUntil

is passed to the Pages Function. https://developers.cloudflare.com/pages/platform/functions#writing-your-first-function My code:

export async function onRequest(context) {
    let forwardedRequest = await caches.default.match(context.request);

    if (!forwardedRequest) {
        forwardedRequest = await fetch("https://plausible.io/js/plausible.outbound-links.js");
        context.waitUntil(caches.default.put(context.request, forwardedRequest.clone()));
    }

    return forwardedRequest;
}

I should note that I am getting this error when running locally,

npx wrangler pages dev

Hmm.. that sounds like the

this

inside

context

isn't bound properly.. but I remember seeing the code that does the binding while investigating something else. This is something the Pages team should have a look at. It is very possible a bug in the

pages dev

part of Wrangler

Hmm.. just had a quick look. Pretty sure I found the issue. But I don't have permissions to release a new version of the bundler/runtime. That will have to wait until one of the UK based Pages Team members wakes up 🙂

Have you got the troublesome line or diff I can take a look at?

Should be a PR up right about now 🙂

Can I get the credit for this bug?

I technically caused it, just... didn't find it first hand

How did you cause it??

I gave the code :p

Oh wait they didn't use my code

I wanted a +1 for my resume under "breaking Cloudflare"

I'll make sure this is brought up in the process

Funnily enough Cloudflare would never considered you to have caused that even if they did use your code..

The person who accepted your code and the person who reviewed your code are at least equally involved..

lol

I am getting the same error for

waitUntil

when deploying, not just locally via

pages dev

(see https://discord.com/channels/595317990191398933/910978223968518144/914538090826182767). Just in case the upcoming fix only applies to

pages dev

.

are pages functions subject to the cap of 100 workers per account?

also if they're going to be sharing a bunch of code, are there any best practices for that?

No, it will fix it for both.. And it shouldn't take too long..

Does Wrangler dev remove "set-cookie" headers? I am setting it in functions middleware with

response.headers.append("Set-Cookie", "test=true")

and it works on the pages platform, just not in Wrangler dev. Other headers are coming through in Wrangler dev.

Not intentionally. If you could quickly write up an issue on the wrangler2 repo (https://github.com/cloudflare/wrangler2/issues/new), that would be fab. Thanks!

What's the correct way to reference environment variables in a pages function?

process.env["SOME_API_KEY"]

does not seem to do the trick