Relative URLs will work just fine for Web Workers, which were the original reason for introducing the `theme_uploads_local` feature
Making them relative will mean that `loadScript()` automatically uses the CDN (when enabled), which is doubly important because our CSP doesn't allow loading theme-javascripts from the host domain when the CDN is enabled.
Due to default CSP web workers instantiated from CDN based assets are still
treated as "same-origin" meaning that we had no way of safely instansiating
a web worker from a theme.
This limits the theme system and adds the arbitrary restriction that WASM
based components can not be safely used.
To resolve this limitation all js assets in about.json are also cached on
local domain.
{
"name": "Header Icons",
"assets" : {
"worker" : "assets/worker.js"
}
}
This can then be referenced in JS via:
settings.theme_uploads_local.worker
local_js_assets are unconditionally served from the site directly and
bypass the entire CDN, using the pre-existing JavascriptCache
Previous to this change this code was completely dormant on sites which
used s3 based uploads, this reuses the very well tested and cached asset
system on s3 based sites.
Note, when creating local_js_assets it is highly recommended to keep the
assets lean and keep all the heavy working in CDN based assets. For example
wasm files can still live on the CDN but the lean worker that loads it can
live on local.
This change unlocks wasm in theme components, so wasm is now also allowed
in `theme_authorized_extensions`
* more usages of upload.content
* add a specific test for upload.content
* Adjust logic to ensure that after upgrades we still get a cached local js
on save
DEV: Replace instances of Discourse.base_uri with Discourse.base_path
This is clearer because the base_uri is actually just a path prefix. This continues the work started in 555f467.
You can now add javascript files under `/javascripts/*` in a theme, and they will be loaded as if they were included in core, or a plugin. If you give something the same name as a core/plugin file, it will be overridden. Support file extensions are `.js.es6`, `.hbs` and `.raw.hbs`.
David Taylor
Sam
Daniel Waterworth
Kane York
Kyle Zhao