[Bug 47850] New: Automatically restart the TestBot Engine if it crashes

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=47850

Bug ID: 47850
           Summary: Automatically restart the TestBot Engine if it crashes
           Product: Wine-Testbot
           Version: unspecified
          Hardware: x86
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: P2
         Component: unknown
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

The CheckWineTestBot.pl script is supposed to automatically restart the TestBot
Engine if it crashes (such as because of a Perl error that only happens in
specific code paths).

However it does not work in the current usage scenario.

I think what happens is that the script is run in a non-root account for
security reasons so the call to 'service winetestbot restart' fails with a
permission denied error.

So a different approach is needed, probably one where there are two scripts:
* One which communicates with the Engine and returns whether it runs. This
script would be run through su.
* And a second script that uses the first script's exit code to decide when to
restart the Engine. It may even be possible to have systemd handle the task of
this second script (to be investigated).

Another totally different approach would be to parse the Engine log and check
the presence of messages logged by SafetyNet() which runs every 10 minutes. But
that would not really guarantee that the Engine is reachable through its
socket.

Yet a third option would be to have systemd start the Engine automatically when
its socket is accessed. That may allow for systemd to automatically restart the
Engine when it crashes (to be investigated).