Launching RStudio results in Server Error

[palermog]

When the image is done building , Juptyer notebook will load, but RStudio will not. Depending on how I try to load it, by using urlpath=rstudio or by clicking the RStudio icon in labs, I'll either get the following error from Jupyter Server:

500 : Internal Server Error
The error was:
could not start rstudio in time

or a browser error of some kind that reports an inability to establish a connection. In Google Chrome, this reads:

This site can’t provide a secure connection

notebooks.gesis.org sent an invalid response.

ERR_SSL_PROTOCOL_ERROR

This is true whether I click the button on your template to build a binder image or I author a postBuild script of my own manually. I unfortunately have no real idea what could be causing this issue. Maybe something to do with runtime versions?

Also, some asides that may warrant its own discussion thread or contribution to the issue on the repo2docker repo, but that came up in the context of working renv into the binderizing process: I'm wondering a bit about the decision in your example here to include the lockfile in the .binder directory. By default at least, renv puts the lockfile in the project's root directory along with an renv subfolder. So, a couple of questions:

• Is it best practice to add this renv subfolder to .gitignore to keep things lightweight?
• If not, renv will boostrap itself when the r session is loaded, so it may not be necessary to install the package again in the postBuild script.
• A suggestion I have would be to use renv::hydrate() instead of renv::restore(), since it's faster. Any downsides to this?