API for getting URLs for JavaScript files?

There is ipywidgets.embed.DEFAULT_EMBED_REQUIREJS_URL, but is there also an API to get the require.js URL?

I could probably use ipywidgets.embed.load_requirejs_template, but I don’t know if that’s part of the public API. Is it?

I’m also not quite sure if I’m supposed to use crossorigin="anonymous" or not. In load_requirejs_template it is hard-coded for one URL, and optional for the other.

In the end, I want to use those URLs in Sphinx, see https://github.com/spatialaudio/nbsphinx/issues/84.

[mgeier]

Is html_js_files just a global in conf.py?

That’s just how the Sphinx configuration works. The global variables are somehow automatically turned into Sphinx options (if those options exist). See http://www.sphinx-doc.org/en/master/usage/configuration.html.

Would it make sense for html_js_files to have this as a default value if not specified?

Well that’s the question!

The problem, as I see it, is that I would always need to import ipywidgets, even for projects which don’t use widgets. I don’t want to have ipywidgets as unconditional dependency.

However, now that I think about it, I might be able to check if widget states are used in any notebook and only import ipywidgets (and in turn include the .js URL) in this case …

In that case though, I shouldn’t use html_js_files, because I cannot detect user overrides (because it might be used for completely different JS files). But I could use a new configuration value, just like I’ve done for nbsphinx_requirejs_path (see https://github.com/spatialaudio/nbsphinx/pull/327). Something like nbsphinx_widgets_path?

Do you think this would be worthwhile?

It sounds promising … fully automatic widget support, but without overhead if widgets are not used.

[mgeier]

I think it would be helpful to mention in the docs that DEFAULT_EMBED_REQUIREJS_URL is considered part of the API.

And it would be good to know if I’m supposed to use crossorigin="anonymous" or not.