I'm not familiar with the dashboard - what information is available to it?  AutoRollers should be straightforward to recognize because they're all using GCE service accounts and thus end with @skia-buildbots.google.com.iam.gserviceaccount.com*

The rollers set the current sheriff as a reviewer on the rolls. It looks like the simplest thing would be to look for a "TBR=" line in the commit message.  We could also add an endpoint to the server to return the current sheriff, but you'd need to parse the server URL out of the commit message in order to do so as well, and that'd rely on the server being up and running (which is normally the case, but we don't have multiple instances or load balancing, so I'd hesitate to make non-Skia services rely on it).

* Note that Skia Infra may end up moving some things around between GCE projects, so it's probably best to do a "looks like a service account" check vs a simple suffix comparison.

Sorry for the slow response! The dashboard normally uses the gitiles API to look up a change, so that it can get an 'author' field that looks like:

{u'time': u'Mon Mar 19 11:06:13 2018', u'name': u'v8-autoroll', u'email': u'v8-autoroll@chromium.org'}

And it gets a 'message' field where it can parse the TBR.

Is there an API it could use to check if 8-autoroll@chromium.org is a GCE service account (or more simply, to get the associated address so we can check if it ends wit @skia-buildbots.google.com.iam.gserviceaccount.com*?

Skia infra actually doesn't control the v8 autoroller.  I suspect it's using a "real" user account, which we used to do before we switched to service accounts, so that's the actual email address.  For Skia Infra managed rollers, the email addresses follow this convention:

<child name>-<parent-name>-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com

That address does show up in the gitiles API, eg. https://paste.googleplex.com/4834293243183104

I am not aware of an API to check whether an email address is a service account.  I don't know how many other types of rollers are out there in the wild; I'm only aware of v8 plus the Skia infra-managed rollers, so it may be enough to say "ends with '.iam.gserviceaccount.com'" and add the v8 roller as a special case.

The following revision refers to this bug:
  https://chromium.googlesource.com/catapult/+/565fe0930e842cc47f52bc4fb8f366a63d120e4d

commit 565fe0930e842cc47f52bc4fb8f366a63d120e4d
Author: Annie Sullivan <sullivan@chromium.org>
Date: Fri May 11 20:31:05 2018

Update bug assigns to autorollers to assign to sheriff.

Bug:  chromium:830667 
Change-Id: Ic243aa5f2faa65bde74396007ccbf72611a177c6
Reviewed-on: https://chromium-review.googlesource.com/1011573
Commit-Queue: Annie Sullivan <sullivan@chromium.org>
Reviewed-by: Simon Hatch <simonhatch@chromium.org>

[modify] https://crrev.com/565fe0930e842cc47f52bc4fb8f366a63d120e4d/dashboard/dashboard/pinpoint/models/change/commit.py
[modify] https://crrev.com/565fe0930e842cc47f52bc4fb8f366a63d120e4d/dashboard/dashboard/pinpoint/models/job.py
[modify] https://crrev.com/565fe0930e842cc47f52bc4fb8f366a63d120e4d/dashboard/dashboard/file_bug_test.py
[modify] https://crrev.com/565fe0930e842cc47f52bc4fb8f366a63d120e4d/dashboard/dashboard/common/utils.py
[modify] https://crrev.com/565fe0930e842cc47f52bc4fb8f366a63d120e4d/dashboard/dashboard/file_bug.py
[modify] https://crrev.com/565fe0930e842cc47f52bc4fb8f366a63d120e4d/dashboard/dashboard/common/utils_test.py
[modify] https://crrev.com/565fe0930e842cc47f52bc4fb8f366a63d120e4d/dashboard/dashboard/pinpoint/models/job_test.py

This should be fixed on the next deploy.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/a5d0a26402764d6d578092c1d9b92bee947aa9a1

commit a5d0a26402764d6d578092c1d9b92bee947aa9a1
Author: catapult-chromium-autoroll <catapult-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Date: Sat May 12 09:08:01 2018

Roll src/third_party/catapult/ 1d2e7600b..b424d15a6 (6 commits)

https://chromium.googlesource.com/catapult.git/+log/1d2e7600b0b4..b424d15a6070

$ git log 1d2e7600b..b424d15a6 --date=short --no-merges --format='%ad %ae %s'
2018-05-11 sammiequon Disable cache_temperature tests on chromeos.
2018-05-11 sullivan Update bug assigns to autorollers to assign to sheriff.
2018-05-11 simonhatch Dashboard - Remove some old logging from graph_data.
2018-05-11 dtu [pinpoint] Don't CC reviewers on bug comments.
2018-05-10 simonhatch Dashboard - Add some logging around /add_histograms.
2018-05-11 simonhatch Pinpoint - Update results2 generator for job format.

Created with:
  roll-dep src/third_party/catapult
BUG= chromium:830667 , chromium:842248 


The AutoRoll server is located here: https://catapult-roll.skia.org

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

If the roll is causing failures, please contact the current sheriff, who should
be CC'd on the roll, and stop the roller if necessary.


TBR=sullivan@chromium.org

Change-Id: I6cfe1c7f4f7b7be60b505b4cae00b27cef8a66fc
Reviewed-on: https://chromium-review.googlesource.com/1056471
Reviewed-by: catapult-chromium-autoroll <catapult-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Commit-Queue: catapult-chromium-autoroll <catapult-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#558127}
[modify] https://crrev.com/a5d0a26402764d6d578092c1d9b92bee947aa9a1/DEPS