Give user an option to run shiny-server as root

[haobibo]

Currently, if the user runs the process of shiny-server in root and defines run_as to root, the shiny-server will abort.
It is possible (and secure) to allow users to run the process in root and run_as root?

[haobibo]

@jcheng5 will appreciate it if you can provide any feedback/comments!

[jcheng5]

I can't in good conscience accept this--the risks are so huge. Is there a reason you can't run as a different user?

[haobibo]

Thank you @jcheng5 for your feedback!

I'm running shiny-server inside a Docker container, which isolates all environment inside the container: both file system and processes:https://github.com/QPod/docker-images

I chose to use the root user inside docker for simplicity reasons, where a user can do everything inside the container, and risks are isolated/controlled by docker.

I understand there is un-ignorable risk to run shiny-server as the root user.
While giving users an option can be helpful to users who intended to run shiny-server as root.
Here are some reference cases which provide an --allow-root in other software/programs:

• Jupyter Notebook --allow-root: refuse to run as root user jupyter/notebook#1115
• Bower --allow-root: https://stackoverflow.com/questions/25672924/run-bower-from-root-user-its-possible-how