it might be the preloads causing that

or your require structure makes it so that code the worker uses also references dom stuff

you probably want something like this

{:shared
 {:entries []}

 :app
 {:init-fn admin.core/init
  :preloads [day8.re-frame-10x.preload]
  :depends-on #{:shared}}

 :posts
 {:entries [admin.posts.views]
  :depends-on #{:app :shared}}

 :analytics
 {:entries [admin.analytics.views]
  :depends-on #{:app :shared}}

 :sessions
 {:entries [admin.sessions.views]
  :depends-on #{:app :shared}}

 :worker
 {:init-fn admin.worker/init
  :web-worker true
  :depends-on #{:shared}}}

with the :devtools entry removed entirely

basically you just need to make sure that nothing from the worker references anything from the other modules (except shared) directly, so no (:require [admin.core :as core]) or whatever

@U05224H0W Hi, thank you so much for replying! I've tried that and now I get the following error:

app.js:1 Uncaught ReferenceError: SHADOW_ENV is not defined
    at app.js:1:1

which is this line:

SHADOW_ENV.evalLoad("shadow.module.app.prepend.js", false, "\nshadow.loader.set_load_start(\x27app\x27);");

but the worker now looks much better. worker.js:

SHADOW_ENV.evalLoad("shadow.module.worker.prepend.js", false , "\nshadow.loader.set_load_start(\x27worker\x27);");
SHADOW_ENV.evalLoad("admin.worker.js", true , "goog.provide(\x27admin.worker\x27);\nadmin.worker.init \x3d (function admin$worker$init(){\nreturn self.addEventListener(\x22message\x22,(function (e){\nreturn postMessage(e.data);\n}));\n});\n");
SHADOW_ENV.evalLoad("shadow.module.worker.append.js", false , "\nshadow.cljs.devtools.client.env.module_loaded(\x27worker\x27);\n\nshadow.loader.set_loaded();\ntry { admin.worker.init(); } catch (e) { console.error(\x22An error occurred when calling (admin.worker/init)\x22); throw(e); };\nSHADOW_ENV.setLoaded(\x22shadow.module.worker.prepend.js\x22);\nSHADOW_ENV.setLoaded(\x22admin.worker.js\x22);\nSHADOW_ENV.setLoaded(\x22shadow.module.worker.append.js\x22);");

in the HTML you need to load the shared.js file prior to the app.js file

the worker does that itself but the app.js file cannot as of now

I added shared.js to HTML and that took care of that error but now when I try to create the worker:

(let [worker (js/Worker. "/js/compiled/worker.js")]
                         (.. worker (addEventListener "message" (fn [e] (js/console.log e))))
                         (.. worker (postMessage "hello world")))

worker.js:1 Uncaught ReferenceError: SHADOW_ENV is not defined
    at worker.js:1:1

SHADOW_ENV.evalLoad("shadow.module.worker.prepend.js", false, "\nshadow.loader.set_load_start(\x27worker\x27);");

oh oops. i forgot the :web-worker true in the build config

for the worker module

The worker says hello world 🙂 . Thank you so much for all your help!

@U05224H0W there is still one problem unfortunately

when I do release I use :module-hashnames option

however worker tries to load importScripts("shared.js") without hash, even though I load the hashed version in html script tag

<script>
    var webWorkerFile="/assets/js/compiled/worker.84D0DF83F3955C46E01ED037C6E5F7C6.js";
</script>
<script src="/assets/js/compiled/shared.7D87480495688DE84B39E87B1A2BDD8F.js"></script>
<script src="/assets/js/compiled/app.08E387C98C9872E160C80225449C162E.js"></script>

and therefore I get the following error:

Uncaught DOMException: Failed to execute 'importScripts' on 'WorkerGlobalScope': The script at '/assets/js/compiled/shared.js' failed to load.
    at /assets/js/compiled/worker.84D0DF83F3955C46E01ED037C6E5F7C6.js:1:1

I did see the option to use

shadow-cljs release app --config-merge '{:release-version "v1"}'

Or can the worker be somehow made to load shared.hash.js (if it cannot do without it)

hashes are tricky as adding the hash to the file changes the hash of the file 😛

it cannot do without it, so it needs to be imported

if you want to setup a repro I can take a look, I just might have forgotten to consider the worker case

nvm I can reproduce it

https://github.com/thheller/shadow-cljs/issues/1165

Thank you for looking into it, I got hungry baby twins screaming at me so no time to setup a repro 🙂