missing hydration in SSR builds

[formsandlines]

When I build a notebook with :ssr true and spin up a local server to load it in the browser, I cannot interact with the interface at all, specifically:

• light-/darkmode switch
• TOC button
• fold/unfold buttons in code viewer
• “elided” buttons in code viewer
• etc.

Nothing happens at all if I click any of these. Event handlers from custom render functions also won’t get triggered.

This is probably due to missing hydration, since there seems to be no code in the generated html file to attach event listeners, etc. I don’t know anything about how SSR works in React, so I hope this is an easy thing to fix.

I created a test repo where I included all the cases listed above and build the notebook so you can see the generated html file: https://github.com/formsandlines/clerk-ssr-interactive-test It uses the latest commit from Clerks main branch.

[borkdude]

I could be wrong but my assumption about SSR support in Clerk is that you can build something more light-weight that doesn't require JavaScript. But hydration is not something that was considered. Perhaps it could be done though. Any thoughts @mk ?

[dobladez]

SSR Hydration would be great! Most notebooks I've seen are purely client-side, right?

Last year I've published a long notebook with heavy custom viewers. It takes seconds to load. Like @formsandlines , I'd assumed :ssr true would've helped.

I haven't touched much Clojure since then, but would be happy to help with this (assuming it's even feasible).

Published notebook: https://neuroning.com/boardgames-exercise/notebooks/walkthrough/
Repo source: https://github.com/dobladez/boardgames-exercise

[formsandlines]

Yeah, I was also working on a larger introduction notebook with custom viewers and render functions that generate lots of SVG nodes. The built without SSR takes seconds to load, but with :ssr true it shows up almost instantly.

However, publishing it without some hydration would only confuse readers and prevent access to basic functionality like TOC, light-/darkmode, etc.

I don’t know what the intended use-case is for the SSR option, but for me it feels incomplete without the hydration.

[dobladez]

Yes, with SSR it does load fast, and it's great for some notebooks. For many other notebooks however (like the one I liked to), it's not an option: interactive viewers don't work at all; it's not just "cosmetic stuff" (like light/dark mode).

Again: I have no idea how hard/feasible it'd be... I don't even know what I'm talking about here... just wished it worked that way 🙂