on CompareGMs failure, show link to most recent results on this builder

master/skia_master_scripts/factory.py

Index: master/skia_master_scripts/factory.py
diff --git a/master/skia_master_scripts/factory.py b/master/skia_master_scripts/factory.py
index 19d0f327aaa40f08c2c318c89cad5faa6c710308..e1d0484d5b271ea4e591abc624b4aa3067cda183 100644
--- a/master/skia_master_scripts/factory.py
+++ b/master/skia_master_scripts/factory.py
@@ -43,6 +43,9 @@ _COMPILE_STEP_PREFIX = 'Build'
 _COMPILE_RETRY_PREFIX = 'Retry_' + _COMPILE_STEP_PREFIX
 _COMPILE_NO_WERR_PREFIX = 'Retry_NoWarningsAsErrors_' + _COMPILE_STEP_PREFIX
 
+# EPOGER: how can I share this definition with compare_gms.py?

[borenet, 2014/06/05 14:36:10]

global_variables.json.

+LATEST_GM_FAILURES_PREAMBLE = 'View latest GM failures for this builder at: '
+
 
 class SkiaFactory(BuildFactory):
   """Encapsulates data and methods common to the Skia master.cfg files."""
@@ -531,6 +534,9 @@ class SkiaFactory(BuildFactory):
     """Compare the actually-generated GM images to the checked-in baselines."""
     self.AddSlaveScript(script='compare_gms.py',
                         description='CompareGMs',
+                        get_props_from_stdout={

[epoger, 2014/06/04 21:55:11]

Unfortunately, this doesn't work.

https://github.com/google/skia-buildbot/blob/master/master/skia_master_script...
only processes get_props_from_stdout if the build step succeeded.  In this case,
the URL is only useful when the test fails. :-(

See
http://c128.i.corp.google.com:10115/builders/Test-Ubuntu13.10-ShuttleA-NoGPU-...
: CompareGMs fails, and its stdio contains the link, but the build does not
display the property.

ALSO- I would rather have the URL be visible under the CompareGMs step on the
build page, rather than being a property of the build as a whole.  It's more
detail that developers want to look at in the context of a single step's
results...

[borenet, 2014/06/05 14:36:10]

We can probably change the logic in
master/skia_master_scripts/skia_build_step.py: SkiaBuildStep.commandComplete,
which currently doesn't bother checking for get_props_from_stdout when the
command failed.  Instead, we could check anyway but avoid raising an Exception
when we don't find a match IF the command failed.

I'm a little confused about what you're asking for with where the link is
displayed.  It should show up under CompareGMs in the list of steps (just like
got_revision shows up under Update) and it should show up in the table of build
properties.  Is that not sufficient?  I don't know if it'll actually be a
clickable link (my guess is no).

[epoger, 2014/06/05 15:08:43]

Ultimately, my vision is of something like
http://build.chromium.org/p/chromium.webkit/builders/WebKit%20Win7/builds/16786
, where the webkit_tests step goes red to show you which TYPE of test failed,
and then you can click on a link right there to see what the specific failures
were.

How can we get there?  Or, is there some other model that's even better?

+                            'latest_gm_failures_url':
+                            '%s(\w+)' % LATEST_GM_FAILURES_PREAMBLE},
                         is_rebaseline_step=True)
 
   def CompareRenderedSKPs(self):