Gracefull shutdown of bottle python server

Question

Hi is there a way out to gracefully shutdown the bottle server. In a way it should be able to do few steps before it eventually stops. This is critical for some clean up of threads and db state etc avoiding the corrupt state during the restart.

I am using mod wsgi apache module for running the bottle server.

Answer 1

In mod_wsgi you can register atexit callbacks and they will be called on normal process shutdown. You don't have too long to do stuff though. If embedded mode, or daemon mode and shutdown caused by Apache restart, you have only 3 seconds as Apache will kill off processes forcibly after that. If daemon mode and trigger is due to touching WSGI script file or you explicitly sent daemon process a signal, you have 5 seconds, which is when mod_wsgi will decide it is taking too long and forcibly kill them.

See the 'atexit' module in Python.