view() shows websockets disconnection

[Ljupch0]

Hi, I am coming back to code that used to work.

Now when calling b$View() I immediately get
"Debugging connection was closed. Reason: WebSocket disconnected"

When I click reconnect devtools it immediately disconnects.

Is this some IT security thing?

[wch]

I think this is the same issue as rstudio/shinytest2#331.

[gadenbuie]

I wonder if it's related to recent changes to headless mode in Chrome? IIUC, as of Chrome 112, headless mode now uses the same engine as headful mode where previously headless mode was a completely separate engine.

I don't know the full context but the timing is suspicious and the linked article mentions the live viewer explicitly, so it seems feasible that something might have changed in that area.

[wch]

It looks like this is due to a security change in Chrome: https://bugs.chromium.org/p/chromium/issues/detail?id=1422444#c5

One workaround is to add --remote-allow-origins=*, but I think that makes it too open. It would be better to use --remote-allow-origins=http:127.0.0.1:xxxx, where xxxx is the port number. However, the problem with that is that we currently don't set the port number -- we let Chrome choose it when we use the option --remote-debugging-port=0. So for a proper fix, we might need to randomly select a port in R, then pass that port number to Chrome when starting it up.

[wch]

I made a workaround for testing in #100. You can try it with:

remotes::install_github("rstudio/chromote@origin-testfix")

[gadenbuie]

@wch Since chromote doesn't currently expose an option to set the port, should it internally find a random port? Or would you prefer to expose an argument for setting the port number?

[wch]

I think it makes sense to always find a random port. I can't think of a reason offhand why one would need a specific port number.

[edwardhealey]

hey @wch, I am still getting the same issue as #99 when I install the package via remotes::install_github("rstudio/chromote") and run

library(chromote)

chrome <- ChromoteSession$new()
chrome$view()

[gadenbuie]

@edwardhealey Are you getting the exact same behavior and error messages? I would expect a slightly different error message to be reported in the R console than was originally reported here. It's possible that error message may be informative. Can you include anything printed in the R console? Can you also please report your operating system and the version of Chrome you're using?

[wch]

@edwardhealey I just bumped the version number to 0.1.1.9001, so please reinstall, test it, and if it still fails, please include the output from sessioninfo::session_info().

[zsigmas]

@edwardhealey For me it seemed that installing the fix provided by wch was not enough, but I needed to also update chromium for the $view to work again. I assume it was the update as in a given moment $view was working with google-chrome (installed after finding this problem to test if that solved the problem, so most recent version) but not in chromium (an undetermined older version).