You can do it this way:
class SessionCleaner
def self.remove_stale_sessions
CGI::Session::ActiveRecordStore::Session.
destroy_all( ['updated_on < ?', 20.minutes.ago] )
end
end
Then just call via cron:
*/10 * * * * ruby /full/path/to/script/runner
-e production "SessionCleaner.remove_stale_sessions"
Above was found via: http://www.realityforge.org/articles/2006/03/01/removing-stale-rails-sessions
Or you can do it all one 1 line:
*/5 * * * * ruby /full/path/to/script/runner -e
production 'CGI::Session::ActiveRecordStore::Session.destroy_all
( ["updated_at < ?",20.minutes.ago ] )' 2>&1
Both will clear out sessions that are 20 minutes old every 10 minutes. Both will work, but they have to load up Rails every time it runs. I came up with the following solution to avoid loading up Rails thus alleviating some server load:
require 'rubygems'
require 'mysql'
db = Mysql.new("localhost", "db_user", "db_user_pw", "db")
query = db.prepare("DELETE FROM `sessions` WHERE
updated_at < NOW() - INTERVAL 20 MINUTE")
query.execute
puts "Removed #{query.affected_rows} Sessions\n"
db.close
Please note that I assume that you have a MySQL database ,have the mysql gem installed and that you are storing your sessions in a table named 'sessions'.
Enjoy!
Stay tuned for a more flexible version that will read in your config/database.yml for your db settings so you don't have to put them in the script itself.