Should Embroider passthrough script attributes?

[bobisjan]

Hi,

should Embroider passthrough the HTML attributes like defer on scripts from app/index.html into dist/index.html for ember build --environment=production?

<!-- app/index.html -->
<script src="{{rootURL}}assets/vendor.js" defer></script>
<script src="{{rootURL}}assets/embroider-playground.js" defer></script>

<!-- dist/index.html -->
<script src="/assets/vendor.js"></script>
<script src="/assets/chunk.c1fdfc6b793b9d023c96.js"></script>
<script src="/assets/chunk.4aecffffbd029f26d4de.js"></script>

Thanks ☺️

---

Just for curiosity why the assets/embroider-playground.js is split into two chunks by default?

[ef4]

In general, yes, we should leave attributes like defer alone.

However, I don't think that actually works reliably in Ember apps in general, with or without embroider. vendor.js must execute before the app, and if you defer both there is a chance that the app will lose the race.

Just for curiosity why the assets/embroider-playground.js is split into two chunks by default?

Webpack's default settings put things from node_modules in a separate chunk from your own project. It's the same reason Ember traditionally splits things into vendor.js and app.js -- the third-party deps are theoretically more slowly changing and can get better cacheability.

Under embroider, we will have some legacy things in vendor.js, but much of what was in there has moved into the node_modules chunk.

[bobisjan]

@ef4, thanks for the explanation 👍

However, I don't think that actually works reliably in Ember apps in general, with or without embroider. vendor.js must execute before the app, and if you defer both there is a chance that the app will lose the race.

This makes me worried 🙈, where does this come from? I live with the following statement

Scripts with the defer attribute will execute in the order in which they appear in the document.

from https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script.

[ef4]

Oops, never mind me, I was mixed up with async.

[rahulk94]

Hey team any updates on this? I'm trying to set type="module" attributes on our application scripts so we can avoid loading them on IE but they're not propagating through. At this point I'm having difficulty figuring out whether this is an embroider issue or ember-auto-import.

[lifeart]

Hi @rahulk94! I think only tests is missing in original PR to move it forward