Feature: URL bookmark support / Update the query string and respond to query string changes

[schloerke]

py-shiny has added bookmark support in v1.4.0 (released Apr 9).

With both R and python Shiny now supporting bookmarking via URL, it would make sense to have shinylive support bookmarking as well.

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I've already crippled serverside bookmarking for python: #206

[willgearty]

@schloerke any idea when bookmarking will come to Shinylive (for R)?

[schloerke]

@georgestagg Any plans?

@willgearty My gut reaction is that priorities are on Positron and it will not be implemented in the near future.

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@willgearty Q: how do you see web pages with multiple shinylive apps handle bookmarking?

[willgearty]

Gotcha, thanks for the quick response @schloerke.

I can't say I have much experience with multiple shinylive apps on a single web page. As it is, bookmarking is disabled by default, right? So implementing this shouldn't have direct impact on such setups (unless someone had erroneously enabled bookmarking)? (although I don't fully know the spiderweb of dependencies on these kinds of things in the shinylive internals)

That being said, with the way URIs are encoded, I don't envision a super elegant way to make this work. Maybe you could have input prefixes that correspond to the individual shinylive apps and their IDs (similar to how inputs in shiny modules work)? Or you could prefix "_inputs_" with the app's ID, and then if another instance of "instance{ID}" shows up in the parameters, you know the following inputs are for a different shinylive app? Just some quick thoughts off the top of my head.

[gadenbuie]

That being said, with the way URIs are encoded, I don't envision a super elegant way to make this work.

This here is the core blocker. shinylive changes the execution model enough that we don't have an easy or obvious path for connecting URL queries to the shinylive app instance. There are lots of options, and we've talked about it more than a few times, but the tradeoffs aren't great.

Here are some past conversations and proposals

• Pass URL query parameters to the Shiny app in Viewer.tsx #79
• updateQueryString doesn't work with shinylive rstudio/shiny#4153
• [bug]: starlette request object does not have the query parameters in shinylive py-shiny#1794
• Allow apps to access the URL parameters #217
• url_search parsing a shinylive app r-shinylive#28