Run Tasks at Session Start or End#

This guide addresses how to set up callbacks when a session is created and destroyed.

Whenever a request is made to an endpoint that is serving a Panel application a new session is created. If you have to perform some setup or tear down tasks on session creation (e.g. logging) you can define on_session_created and on_session_destroyed callbacks.




In many cases it is useful to define on_session_destroyed callbacks to perform any custom cleanup that is required, e.g, dispose a database engine, log out a user etc.

The callbacks must have the signature

def callback(session_context):

and can be registered with pn.state.on_session_destroyed(callback).