How to use non-default browser?

Question

I have an R package that triggers Oauth2 flow in the browser (via httr). A user is in the odd situation that their IT department requires a specific system default browser (in this case, it's IE + Windows). But the user needs to do the OAuth in a different browser.

I am aware of the R_BROWSER environment variable and would like to temporarily set it to the browser of need. (And then hope that will be honoured in the OAuth flow...)

I am fiddling with this on a Mac and my default browser is Safari. My usual situation wrt R_BROWSER is this

Sys.getenv("R_BROWSER")
#> [1] "/usr/bin/open"

I know how to force the use of, e.g., Chrome from the shell or, from R, with a system() call:

system("/usr/bin/open -a '/Applications/Google Chrome.app' 'http://slate.com'")

But how do I transfer that knowledge to an appropriate setting for R_BROWSER? This does not work:

Sys.setenv("R_BROWSER" = "/usr/bin/open -a '/Applications/Google Chrome.app'")

When I subsequently browseURL(), the usual Safari default gets used. I suspect the answer differs by OS. For Mac OS, it seems desirable to avoid using open and somehow specify the browser directly.

Answer 1

First, you should also save the previous values of both browser option and R_BROWSER so that you can restore the previous state of the session:

old_R_BROWSER <- Sys.getenv("R_BROWSER")
old_browser <- options()$browser

Then you can achieve desired behaviour by re-running the command @Hack-R posted after setting R_BROWSER.

Sys.setenv("R_BROWSER" = "/usr/bin/open -a '/Applications/Safari.app'")
options(browser = as.vector(Sys.getenv("R_BROWSER")))
browseURL("http://www.google.com") # opens in Safari, though my default is Chrome

(You can also just directly set options(browser = "/usr/bin/open -a '/Applications/Safari.app'") and browseURL works.)

Finally, restore the system state

Sys.setenv("R_BROWSER" = old_R_BROWSER)
options(browser = old_browser)