Re: automatically showing test-suite.log on failure?

[Eric Blake]

[adding autoconf, as this also affects testsuite.log generated by 
projects using autotest instead of automake's built-in support]

On 9/21/18 12:37 PM, Bob Proulx wrote:
> Bob Friesenhahn wrote:
> > Karl Berry wrote:
> > > However, this seems like it would be fairly commonly useful and easy
> > > enough to do in the canonical test-driver script. So, any chance of
> > > adding it as a standard feature? Any reasonable way of enabling it would
> > > be fine, e.g., a flag that can be added to [AM_]LOG_DRIVER_FLAGS.
> >
> > Take care since some test logs could be megabytes in size.
>
> I want to put a point in that often users try to be helpful and email
> that multi-megabyte log file as an email attachment to bug reporting
> mailing lists that sometimes have a lot of subscribers.  This is very
> painful on the network bandwidth usage.  And also every downstream
> subscriber, perhaps on a metered cell modem data plan, pays the cost
> of receiving it whether they can help with it or not.
>
> If there is some way, clever or not, to encourange the user to
> compress that log file before attaching it that would save a lot of
> downstream pain.  When compressed that log file is a small fraction of
> the original size and rarely a problem.
>
> Just mentioning it to keep it in the brain cache when thinking about
> improvements here.  :-)

Indeed - I almost wonder if it would be worth patching the sequences 
that generate testsuite.log to automatically generate a compressed 
version in parallel, and in the output when a test fails, mention that 
the user may inspect testsuite.log but should email the compressed 
testsuite.log.XYZ to the developer.  Determining the best compression 
program to recommend is interesting - if the user is testing a package 
that shipped only as foo.tar.xz, then testsuite.log.xz makes the most 
sense to generate; but if foo ships both foo.tar.gz and foo.tar.xz, it 
is not obvious which form the user uncompressed and would require a 
configure or runtime probe for which compression engine to attempt.

If nothing else, autoconf should be patched where it states:

  echo
  if $at_debug_p; then
    at_msg='per-test log files'
  else
    at_msg="\`${at_testdir+${at_testdir}/}$as_me.log'"
  fi
  AS_ECHO(["Please send $at_msg and all information you think might help:

in lib/autotest/general.m4, to mention the recommendation for compression.

--
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
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