Milo: Prefetch logs that are failures

Milo: Prefetch logs that are failures 

This makes click on failure logs super fast.

BUG=639071
Committed: https://github.com/luci/luci-go/commit/20b5b559d1cddeb3163c69a15e64f971f6bcdfa6

[Ryan Tseng, 2016-08-18 21:12:16]

The CQ bit was checked by hinoka@google.com to run a CQ dry run

[commit-bot: I haz the power, 2016-08-18 21:12:19]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Ryan Tseng, 2016-08-18 21:20:52]

Description was changed from

==========
Milo: Prefetch stuff

BUG=
==========

to

==========
Milo: Prefetch logs that are failures 

This makes click on failure logs super fast.

BUG=639071
==========

[Ryan Tseng, 2016-08-18 21:20:52]

hinoka@google.com changed reviewers:
+ agable@chromium.org

[commit-bot: I haz the power, 2016-08-18 21:22:09]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-08-18 21:22:10]

Dry run: This issue passed the CQ dry run.

[Ryan Tseng, 2016-08-18 21:39:44]

This worked, surprisingly, demo:
https://1072-6196745-tainted-hinoka-dot-luci-milo.appspot.com/swarming/task/3...
(load, wait 2s for prerender to complete, click on stdout for failing step)

Milo limits itself to 3 prefetched links.

[Ryan Tseng, 2016-08-18 21:40:06]

The CQ bit was checked by hinoka@google.com to run a CQ dry run

[commit-bot: I haz the power, 2016-08-18 21:40:18]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[agable, 2016-08-18 21:44:11]

https://codereview.chromium.org/2250263005/diff/20001/milo/appengine/frontend...
File
milo/appengine/frontend/expectations/buildbot-swarming.TestableBuild-build-canceled.html
(right):

https://codereview.chromium.org/2250263005/diff/20001/milo/appengine/frontend...
milo/appengine/frontend/expectations/buildbot-swarming.TestableBuild-build-canceled.html:17:

Why do these expectations get extra empty lines? I mean it's not inherently a
bad thing, it just seems like "change X shouldn't touch file Y at all" is a nice
invariant to have.

https://codereview.chromium.org/2250263005/diff/20001/milo/appengine/swarming...
File milo/appengine/swarming/build.go (right):

https://codereview.chromium.org/2250263005/diff/20001/milo/appengine/swarming...
milo/appengine/swarming/build.go:402: // URLs to prefetch.
Any reason the list of urls isn't part of an "interestingURLs" parameter on the
MiloBuild object, or something like that? Maybe that wouldn't be very Go-ish, I
dunno, just figured I'd ask.

[commit-bot: I haz the power, 2016-08-18 21:47:26]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-08-18 21:47:27]

Dry run: This issue passed the CQ dry run.

[Ryan Tseng, 2016-08-18 22:03:58]

The CQ bit was checked by hinoka@google.com to run a CQ dry run

[commit-bot: I haz the power, 2016-08-18 22:04:16]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Ryan Tseng, 2016-08-18 22:09:31]

The CQ bit was checked by hinoka@google.com to run a CQ dry run

[commit-bot: I haz the power, 2016-08-18 22:09:35]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[Ryan Tseng, 2016-08-18 22:09:45]

https://codereview.chromium.org/2250263005/diff/20001/milo/appengine/frontend...
File
milo/appengine/frontend/expectations/buildbot-swarming.TestableBuild-build-canceled.html
(right):

https://codereview.chromium.org/2250263005/diff/20001/milo/appengine/frontend...
milo/appengine/frontend/expectations/buildbot-swarming.TestableBuild-build-canceled.html:17:

On 2016/08/18 21:44:11, agable wrote:
> Why do these expectations get extra empty lines? I mean it's not inherently a
> bad thing, it just seems like "change X shouldn't touch file Y at all" is a
nice
> invariant to have.

That's because I wasn't using {{- .Statement -}}, so any formatting padding also
gets interpreted as padding to get rendered, eg when i added new {{ if stuff }}
statements.  It's been fixed.

https://codereview.chromium.org/2250263005/diff/20001/milo/appengine/swarming...
File milo/appengine/swarming/build.go (right):

https://codereview.chromium.org/2250263005/diff/20001/milo/appengine/swarming...
milo/appengine/swarming/build.go:402: // URLs to prefetch.
On 2016/08/18 21:44:11, agable wrote:
> Any reason the list of urls isn't part of an "interestingURLs" parameter on
the
> MiloBuild object, or something like that? Maybe that wouldn't be very Go-ish,
I
> dunno, just figured I'd ask.

Originally the thought was that this would manifest itself differently in the
html version and the grpc version, so an html-only hack was good enough.  After
thinking about it a little more, it makes more sense to mark each URL as
interesting or not interesting, and have the templates take care of adding the
prefetch hints.

The downside is the go template engine isn't powerful enough to stop at some
predefined number, so all failures will now be prefetched.  But that's probably
fine too, because they're hints after all.  If everything were failures, then
they're probably all interesting, and it's up to the web browser to decide
wither or not to follow those hints.

[Ryan Tseng, 2016-08-18 22:16:12]

URL fix

[Ryan Tseng, 2016-08-18 22:16:14]

The CQ bit was checked by hinoka@google.com to run a CQ dry run

[commit-bot: I haz the power, 2016-08-18 22:16:25]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-08-18 22:24:35]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-08-18 22:24:36]

Dry run: This issue passed the CQ dry run.

[agable, 2016-08-19 17:15:20]

LGTM this looks great

[Ryan Tseng, 2016-08-19 17:21:50]

The CQ bit was checked by hinoka@google.com

[commit-bot: I haz the power, 2016-08-19 17:21:54]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-08-19 17:26:30]

Description was changed from

==========
Milo: Prefetch logs that are failures 

This makes click on failure logs super fast.

BUG=639071
==========

to

==========
Milo: Prefetch logs that are failures 

This makes click on failure logs super fast.

BUG=639071

Committed:
https://github.com/luci/luci-go/commit/20b5b559d1cddeb3163c69a15e64f971f6bcdfa6
==========

[commit-bot: I haz the power, 2016-08-19 17:26:31]

Committed patchset #5 (id:80001) as
https://github.com/luci/luci-go/commit/20b5b559d1cddeb3163c69a15e64f971f6bcdfa6