@markx I actually don't like it much. the interceptor design is better in general but some design choices are weird

I liked the fact that Pedestal was ready to go for “production” with some logging etc (and also I liked the interceptor concept). No regrets so far for using it, as you can reuse all the ring middleware out there.

Hi, I'm fairly new shadow-cljs, but very impressed so far. I'm having an issue though where I get a Uncaught ReferenceError: regeneratorRuntime is not defined message in the browser console. I'm using the npm workbox-precaching package (in a service worker) and the error is occurring in one of the source files this uses (`node_modules/workbox-core/_private/quota.mjs`). It seems that this file (that uses async/`await`) is getting transpiled to ES5 and the transpiled version is expecting a global regeneratorRuntime to be defined:

var executeQuotaErrorCallbacks = function () {
  var _ref = global.shadow.js.babel.asyncToGenerator( /*#__PURE__*/regeneratorRuntime.mark(function _callee() {
    var _iteratorNormalCompletion, _didIteratorError, _iteratorError, _iterator, _step, callback;

    return regeneratorRuntime.wrap(function _callee$(_context) {

As a workaround, I've found I can get this to work by prepending the JS file that defines regeneratorRuntime (https://raw.githubusercontent.com/facebook/regenerator/master/packages/regenerator-runtime/runtime.js) to my worker.js file that shadow-cljs generates. Is there a mechanism in shadow-cljs that will allow me to prepend some JS to a module?

@mike469 what do you require? by default it should be using the node_modules/workbox-precaching/dist/workbox-precaching.prod.js. which doesn't work either but for different reasons?

I'm doing (:require ["workbox-precaching/precacheAndRoute.mjs" :refer (precacheAndRoute)]) currently which is causing the regeneratorRuntime error. I don't seem to have a dist dir in node_modules/workbox-precaching

hmm which version do you use? I just installed [email protected]

but yeah including the .mjs directly will skip the prod file

my current versions are: ` "workbox-precaching": "^4.1.1", "workbox-routing": "^4.2.0", "workbox-strategies": "^4.2.0"

not sure why there would be no dist, I just npm install'd them

so the problem is that the babel parts are not meant to rewrite the async/await at all

but for some reasons they do

I'm only using babel to rewrite import -> require since it works differently than what the closure compiler does

non standard behavior that is the cause of many headaches ...

hmm yeah the code is pushing my simple babel interop a bit too far

hmm I see, so have you managed to get workbox-precaching working with shadow-cljs previously? Perhaps I just need to figure out why I'm missing the 'dist' versions?

no I haven't worked with that through shadow-cljs

I tried using the workbox cli directly and use that output

the dist files don't work either so don't worry about it

ah ok, so is it babel that inserts the regenerator references?

yes

the problem is polyfilling ...

that is currently not configurable for node_modules files

it shouldn't touch this at all and just leave async/await as they are as server workers support that

so usually you'd set :compiler-options {:output-feature-set :es7} (or whatever async/await was)

and the compiler would leave it alone

yes I did try that but found it had no effect

but that doesn't yet work for node_modules since it goes through some naive babel processing first

I had to go through babel since babel added some non-standard ESM->CJS interop that lots of npm libs rely on

the google closure compiler only allows the strict interop and breaks many packages

something like https://github.com/google/closure-compiler/issues/3308

I can try something maybe that helps

FYI adding the regenerator-runtime/runtime.js verbatim to the start of my generated worker js bundle does fix it for me in this instance

yes but the point is that all that is not required

(I'm only testing in dev mode currently)

service-workers support async/await so they should not be rewritten to add that huge regenerator crap

Right yes understood. I have to go out now but thanks for your help and drop me a message if you want me to try anything out