Persist R function defined in Rprofile even if user clears environment

I have an rprofile that is used for multiple users spinning up sessions in a shared jupyterhub. In it I define a function that sets some parameters for closing out idle sessions (basically it periodically checks when the user activity was and if it was last a threshold, it kills the session). But, if a user clears their workspace/environment, it deletes that function and no longer has it running. Can I get around this somehow? I’ve tried:

defining it in a separate env in the rprofile including it in a finalizer in the r profile (but that only runs on shutdown, not clearing environment/workspace) using gdata::keep in the r profile telling people not to clear their environment (jk but kinda not, obviously impractical) Any suggestions? For reference if it helps, this is the code I need to persist/keep running:

# track last activity
  update_activity <- function(expr, value, ok, visible) {
    assign(".last_activity", Sys.time(), envir = .GlobalEnv)
    #cat(sprintf("[watchdog] Updated at %s\n", Sys.time()))
    return(TRUE)
  }
  addTaskCallback(update_activity, name = "update_activity")
# check how long since last activity
  check_idle <- function(timeout_minutes = 1) { # minutes
    now <- Sys.time()
    idle_time <- as.numeric(difftime(now, .GlobalEnv$.last_activity, units = "mins"))
    #cat(sprintf("[watchdog] Idle for %.2f minutes\n", idle_time))
if (idle_time > timeout_minutes) {
      cat("Session has been idle too long — exiting.\n")
      .Last()
      q("no")
    } else {
      later::later(function() {
        check_idle(timeout_minutes)
      }, delay = 60) # note - seconds!
    }
}
  later::later(function() {
    check_idle(180) # minutes
  }, delay = 60) # seconds

Solution

Edit: changed from using rlang::env_unlock() (which is deprecated) to something more local.

Somes notes about this:

I'm using dot-names, mostly because it is one-step more to "find" them for users, dot-names tend to be omitted (though search() shows it clearly)
I changed the delays/limits here for local testing
I uncommented/added cat(..) messages for local validation
remove .Last(), since on testing my session complained about could not find function ".Last" ... and since q() will call this function anyway, I think it duplicative

.no_idle <- new.env()
.no_idle$.update_activity <- function(expr, value, ok, visible) {
  assign(".last_activity", Sys.time(), envir = as.environment(".no_idle"))
  cat(sprintf("[watchdog] Updated at %s\n", Sys.time()))
  return(TRUE)
}
.no_idle$.last_activity <- Sys.time()
.no_idle$.check_idle <- function(timeout_minutes = 1) { # minutes
  env <- as.environment(".no_idle")
  now <- Sys.time()
  idle_time <- as.numeric(difftime(now, env$.last_activity, units = "mins"))
  cat(sprintf("[watchdog] Idle for %.2f minutes\n", idle_time))
  if (idle_time > timeout_minutes) {
    cat("Session has been idle too long — exiting.\n")
    q("no")
  } else {
    cat("Session is still being used.\n")
  }
  later::later(function() {
    env$.check_idle(timeout_minutes)
  }, delay = 15) # note - seconds!
}

It worked:

attach(.no_idle)
rm(.no_idle)
search()
#  [1] ".GlobalEnv"        ".no_idle"          "ESSR"              "package:stats"     "package:graphics"  "package:grDevices" "package:utils"    
#  [8] "package:datasets"  "package:r2"        "package:methods"   "Autoloads"         "package:base"     
addTaskCallback(as.environment(".no_idle")$.update_activity, name = "update_activity")
# update_activity 
#               1 
# [watchdog] Updated at 2025-06-02 20:19:09.435791

later::later(as.environment(".no_idle")$.check_idle(), delay = 15)
# [watchdog] Idle for 0.00 minutes
# Session is still being used.
# [watchdog] Updated at 2025-06-02 20:19:09.505805

ls(all.names = TRUE)
# [1] ".Random.seed"
# [watchdog] Updated at 2025-06-02 20:19:17.225449
# [watchdog] Idle for 0.12 minutes
# Session is still being used.
# [watchdog] Idle for 0.37 minutes
# Session is still being used.
# [watchdog] Idle for 0.62 minutes
# Session is still being used.

1
# [1] 1
# [watchdog] Updated at 2025-06-02 20:20:12.52559
# [watchdog] Idle for 0.14 minutes
# Session is still being used.
# [watchdog] Idle for 0.39 minutes
# Session is still being used.
# [watchdog] Idle for 0.64 minutes
# Session is still being used.
# [watchdog] Idle for 0.89 minutes
# Session is still being used.
# [watchdog] Idle for 1.14 minutes
# Session has been idle too long — exiting.
# Process R:2 finished at Mon Jun  2 20:21:24 2025