Move "inline" save functionality from altair_saver into altair?

[joelostblom]

Since we now have vl-convert as the main saving functionality, it could make sense to move some functionality from altair_saver that is not covered by vl-convert into the altair library itself. At least functionality pertaining to saving HTML files, since this operation is already possible in altair without any additional library.

For this issue I am mostly thinking of moving the "inline" parameter into core from saver as mentioned in vega/vl-convert#33 (comment). It seems like there is only string manipulation involved in using the "inline" parameter https://github.com/altair-viz/altair_saver/blob/f5c11bb94562dee73b614255dc1122f948971479/altair_saver/savers/_html.py

[jonmmease]

I'll pick this up, feel free to assign me.

[jonmmease]

It looks like the inline Vega/Vega-Lite source is currently pulled from altair_viewer. Does that still sound like a good idea? Altair viewer seems like a still useful package, but does it make sense to require it in order for the chart.save("file.html", inline=True) to work?

[joelostblom]

Hmm, I feel a bit unqualified to make the call of whether we should move that code into altair code. From a user perspective I would prefer if all saving functionality was covered by the core library and the saving-related packages such as vl-convert. Although it does seems like quite a lot of code.

Do you think including that part in altair would facilitate implementation of #2797?

[jonmmease]

Looks like it would be about 1MB (uncompressed) to add Vega, Vega-Lite, and Vega-Embed to the Altair package. Here's a PR that follow altair_saver by pulling the bundles from altair_viewer: #2807.

Also happy to look at bringing the bundles over to Altair if that's the direction we want to go.

[joelostblom]

Implemented in #2807