[Buildbot-commits] [Buildbot] #2183: SVNPoller stops after failure

[Buildbot]

#2183: SVNPoller stops after failure
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Reporter:  fgsch     |       Owner:
    Type:  defect    |      Status:  new
Priority:  critical  |   Milestone:  0.8.6
 Version:  0.8.5     |  Resolution:
Keywords:            |
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Comment (by dustin):

 I may need some more information here.

 The first error is expected -- it's reporting a failure -- but I don't see
 how that would stop the poller from doing its polling thing.  The string
 "Error in  while polling" is from
 {{{
 #! python
         d.addErrback(log.err, 'SVNPoller: Error while polling:') # eat
 errors
         return d
 }}}
 in `poll()`.  That's an unconditional "if an error occurs, log it and
 resume normal processing of the deferred".  So that deferred's next value
 is a successful None.

 Back in `base.py`, `poll()` is called in
 {{{
 #! python
         def do_poll():
             d = defer.maybeDeferred(self.poll)
             d.addErrback(log.err, 'while polling for changes')
             return d
 }}}
 which is *another* unconditional catch-all.  And while your log snippets
 are abbreviated, I assume you would have included this output if it
 existed.  That it doesn't makes sense - that deferred was successful.  So
 the LoopingCall has no reason to stop looping.

 Now, the second error, almost two minutes later:
 {{{
 2012-01-20 02:32:25+0000 [-] Unhandled error in Deferred:
 }}}
 That's clearly not related to the *same* failure as two minutes earlier,
 and in fact it's not obvious that's related to svn at all.  Looking at the
 invocations of `getProcessOutput` in the poller, all feed their deferreds
 back into the main `poll` deferred, which as we've seen is protected
 against unhandled errors.

 I think the next step is to figure out what that second, unhandled error
 is about, as that will point us to the bug.  Can you tell what was around
 that in the logs?  If not, we may need to add some debugging code.

-- 
Ticket URL: <http://trac.buildbot.net/ticket/2183#comment:2>
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