stopapp without active session?

shiny
,
#1

i am hosting multple shiny apps with local server and wondering how can the server be stopped at given time point (e.g. 9 pm every day) automatically without any active session. The stopapp function seems to work in shinyServer function only and thus require at least one session.

current code:

   observe({
     invalidateLater(60000, session = NULL)
     if(Sys.time() > as.POSIXct(paste(format(Sys.Date(),"%Y-%m-%d" ), " 21:00:00" ), format = "%Y-%m-%d %H:%M:%S")){
       stopApp()
     }
   })