idle_check kills terminal-only sessions prematurely

[rylandely]

It appears that the clock starts ticking for new apps with the first call to idle_check, when the app name is registered. However, this reference time does not seem to be refreshed at any point. Consequently, when working at the terminal with keep_terminals = False and without any notebook running, the app will be terminated with a log message of "Keep alive time for terminal reached". Is this intended behavior? Ideally the IdleChecker would look to see if the terminal is in active use (maybe by resource usage or the output of the w command).

[rylandely]

I'm suggesting something along the lines of replacing idle_checker.py#L272-L276 with

mintime = float('inf')
for term in os.listdir('/dev/pts'):
    if term == 'ptmx': continue
    atime = os.stat(f'/dev/pts/{term}').st_atime
    now = time.time()
    delta = now - atime
    if delta < mintime:
        mintime = delta

if mintime > self.idle_time:
    self.log.info(
        "All terminals exceed keepalive time : " + str(app_name)
    )
    await self.delete_application(app_name)