onStop(fun, session = getDefaultReactiveDomain())

## Only run this example in interactive R sessions
if (interactive()) {
  # Open this application in multiple browsers, then close the browsers.
  shinyApp(
    ui = basicPage("onStop demo"),

    server = function(input, output, session) {
      onStop(function() cat("Session stopped\n"))
    },

    onStart = function() {
      cat("Doing application setup\n")

      onStop(function() {
        cat("Doing application cleanup\n")
      })
    }
  )
}
# In the example above, onStop() is called inside of onStart(). This is
# the pattern that should be used when creating a shinyApp() object from
# a function, or at the console. If instead you are writing an app.R which
# will be invoked with runApp(), you can do it that way, or put the onStop()
# before the shinyApp() call, as shown below.

## Not run: 
# ==== app.R ====
cat("Doing application setup\n")
onStop(function() {
  cat("Doing application cleanup\n")
})

shinyApp(
  ui = basicPage("onStop demo"),

  server = function(input, output, session) {
    onStop(function() cat("Session stopped\n"))
  }
)
# ==== end app.R ====


# Similarly, if you have a global.R, you can call onStop() from there.
# ==== global.R ====
cat("Doing application setup\n")
onStop(function() {
  cat("Doing application cleanup\n")
})
# ==== end global.R ====

## End(Not run)