Making this higher priority because this is blocking https://bugs.chromium.org/p/skia/issues/detail?id=6611

It will not block the transition of CT GCE bots but will block the transition of Skia GCE bots because they require the CIPD client.

Could somebody please take a look? Thanks!

swarming bot downloads CIPD client using cipd.py's _fetch_cipd_client https://cs.chromium.org/chromium/infra/luci/client/cipd.py?q=cipd.py+package:%5Echromium$&l=346
it uses net.py

net.py specifically turns off authentication for GS URLs
https://cs.chromium.org/chromium/src/tools/swarming_client/utils/net.py?q=net.py&dr&l=241
however, the underlying Engine may not have this logic. I could not find usages of set_engine_class. I assume it should be called to set an engine that supports service accounts.

Looks like GS URL Regex is wrong https://codereview.chromium.org/2921943002

The following revision refers to this bug:
  https://chromium.googlesource.com/external/github.com/luci/luci-py.git/+/4b43f73977f9a432219b48f0e7548f2a6e3e2ab5

commit 4b43f73977f9a432219b48f0e7548f2a6e3e2ab5
Author: nodir <nodir@chromium.org>
Date: Fri Jun 02 17:30:10 2017

Fix GS URL regex

R=vadimsh@chromium.org
Bug:  728723 
Review-Url: https://codereview.chromium.org/2921943002

[modify] https://crrev.com/4b43f73977f9a432219b48f0e7548f2a6e3e2ab5/client/utils/net.py

The following revision refers to this bug:
  https://chromium.googlesource.com/external/github.com/luci/luci-py.git/+/4b43f73977f9a432219b48f0e7548f2a6e3e2ab5

commit 4b43f73977f9a432219b48f0e7548f2a6e3e2ab5
Author: nodir <nodir@chromium.org>
Date: Fri Jun 02 17:30:10 2017

Fix GS URL regex

R=vadimsh@chromium.org
Bug:  728723 
Review-Url: https://codereview.chromium.org/2921943002

[modify] https://crrev.com/4b43f73977f9a432219b48f0e7548f2a6e3e2ab5/client/utils/net.py

I retried the task and it was successful: https://chrome-swarming.appspot.com/task?id=369141bcbd1cdb10&refresh=10&show_raw=1

Thanks!

The retried task has "service account: none", so it's not using authentication and can't act as confirmation for the fix. 

I see that retrying tasks drops "service account" setting :( 

Oh, I did not notice that. Thanks for the catch. Reopening till we can confirm.

Confirmed with https://chrome-swarming.appspot.com/task?id=3692e34e12bfca10&refresh=10&show_raw=1

Filed: https://bugs.chromium.org/p/chromium/issues/detail?id=729728