[tor-bugs] #16296 [Onionoo]: Implement lock file in a more robust way

[Tor Bug Tracker & Wiki]

#16296: Implement lock file in a more robust way
---------------------+---------------------
 Reporter:  karsten  |          Owner:
     Type:  defect   |         Status:  new
 Priority:  normal   |      Milestone:
Component:  Onionoo  |        Version:
 Keywords:           |  Actual Points:
Parent ID:           |         Points:
---------------------+---------------------
 The current lock file gets written when the hourly updater starts and gets
 deleted when it exits.  It's really good in preventing concurrent
 executions.  But it doesn't handle cases when a process doesn't exit
 cleanly, because subsequent executions won't start at all.  One
 possibility for not exiting cleanly is that the machine gets rebooted
 while the hourly updater is running.

 One way to fix this might be to use
 [http://docs.oracle.com/javase/7/docs/api/java/nio/channels/FileLock.html
 Java's FileLock] instead of making up our own lock file.

 This is more a defect than an enhancement, because it broke the main
 Onionoo service instance.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/16296>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
The Tor Project: anonymity online