[Findit] Strip platform from step_name before triggering try job.

appengine/findit/waterfall/trigger_swarming_task_pipeline.py

Index: appengine/findit/waterfall/trigger_swarming_task_pipeline.py
diff --git a/appengine/findit/waterfall/trigger_swarming_task_pipeline.py b/appengine/findit/waterfall/trigger_swarming_task_pipeline.py
index 63c4393bdeb33bd566f1235169677e787ecc253a..b82c0da10e69ac6a4cf863a39defaa4c9ca0aa27 100644
--- a/appengine/findit/waterfall/trigger_swarming_task_pipeline.py
+++ b/appengine/findit/waterfall/trigger_swarming_task_pipeline.py
@@ -54,6 +54,7 @@ def _CreateNewSwarmingTaskRequest(
   ]
 
   # Reset tags for searching and monitoring.
+  ref_name = swarming_util.GetTagValue(new_request.tags, 'name') or step_name

[stgao, 2016/03/10 23:50:28]

Should get from the `ref_request` instead, right?

[stgao, 2016/03/10 23:50:28]

And should not default to the step_name.

[stgao, 2016/03/10 23:50:28]

I'm wondering why don't we get the name from the check_first_failure
stage/pipeline. Didn't we query all tasks for all Swarming steps earlier before
triggering any Swarming task?

Is there a reason we do it here instead of an earlier stage?

[chanli, 2016/03/11 00:49:41]

No, this is the referred task, the tag is 'name', 'ref_name' is the tag I added
to the findit tasks.

[chanli, 2016/03/11 00:49:41]

Done.

[chanli, 2016/03/11 00:49:41]

If we get the name when we list swarming tasks in detect_first_failure_pipeline,
we need to either carry it along the pipeline or save it somewhere and retrieve
it later...

While we are already parsing the referred request here, I think the name can be
treated as a part of request (in tags) anyway.

[stgao, 2016/03/11 01:03:20]

My thought is that ref_request is the original data (source of truth), while
new_request is not the source of truth. And we clear new_request.tags after this
line.

[chanli, 2016/03/11 03:47:00]

But before you clear new_request.tags, the tags in it are deepcopied from
ref_request. I don't see any problems here. If you still have doubt, I can
change it to

ref_name = swarming_util.GetTagValue(new_request.tags, 'name') or step_name

Although they are the same to me.

[stgao, 2016/03/11 06:42:58]

Using either new_request.tags or ref_request.tags has the same effect from the
perspective of program.
However, from the perspective of coding style, I believe using ref_request is
the right way to go.

   new_request.tags = []
   new_request.tags.append('purpose:deflake')
   new_request.tags.append('ref_master:%s' % master_name)
@@ -61,6 +62,7 @@ def _CreateNewSwarmingTaskRequest(
   new_request.tags.append('ref_buildnumber:%s' % build_number)
   new_request.tags.append('ref_stepname:%s' % step_name)
   new_request.tags.append('ref_task_id:%s' % ref_task_id)
+  new_request.tags.append('ref_name:%s' % ref_name)
 
   return new_request