Bugdroid already has basic monitoring. It uses the outer_loop library, which sends some default metrics. Unfortunately it appears that it fails to flush those default metrics every time:
https://luci-logdog.appspot.com/v/?s=infra-internal%2Fbb%2Finternal.infra.cron%2Fbugdroid%2F38282%2F%2B%2Frecipes%2Fsteps%2Fbugdroid%2F0%2Fstdout

I don't know what to do about that, since it seems to be using the same stuff as gsubtreed, which sends metrics just fine.

Once that's fixed, I'll be happy to add additional metrics for things we care about, like success/failure of parsing logs and success/failure of posting updates.

I'd noticed that error as well in some other logs :/  Looks like it's been broken for a while - weird we're only just noticing it now.  I'll fix it.

The following revision refers to this bug:
  https://chromium.googlesource.com/infra/infra.git/+/2df465d6546eeed8abf14613bf533b31163fa707

commit 2df465d6546eeed8abf14613bf533b31163fa707
Author: David Sansome <dsansome@chromium.org>
Date: Thu Feb 02 07:29:46 2017

Hide DistributionMetric, force people to use one of the subclasses.

BUG= 687521 

Change-Id: I3629fd75d737e55c2ae4c250810f7184e1427acb
Reviewed-on: https://chromium-review.googlesource.com/435183
Commit-Queue: Dave Sansome <dsansome@chromium.org>
Reviewed-by: Sergey Berezin <sergeyberezin@chromium.org>

[modify] https://crrev.com/2df465d6546eeed8abf14613bf533b31163fa707/packages/infra_libs/infra_libs/ts_mon/__init__.py
[modify] https://crrev.com/2df465d6546eeed8abf14613bf533b31163fa707/packages/infra_libs/infra_libs/ts_mon/common/metrics.py
[modify] https://crrev.com/2df465d6546eeed8abf14613bf533b31163fa707/packages/infra_libs/infra_libs/ts_mon/common/test/metrics_test.py
[modify] https://crrev.com/2df465d6546eeed8abf14613bf533b31163fa707/packages/infra_libs/setup.py

The following revision refers to this bug:
  https://chromium.googlesource.com/infra/infra.git/+/a8d18a31ba11b7a62018326b3002e8278746ccda

commit a8d18a31ba11b7a62018326b3002e8278746ccda
Author: David Sansome <dsansome@chromium.org>
Date: Thu Feb 02 08:16:22 2017

Roll infra_libs in infra and fix outer_loop's usage of DistributionMetric

BUG= 687521 , 684667 
TBR=sergeyberezin

Change-Id: I1b57d624ed54cfc42204ef1242ba9ff8627a0583
Reviewed-on: https://chromium-review.googlesource.com/435121
Reviewed-by: Dave Sansome <dsansome@chromium.org>
Commit-Queue: Dave Sansome <dsansome@chromium.org>

[modify] https://crrev.com/a8d18a31ba11b7a62018326b3002e8278746ccda/appengine_module/gae_ts_mon/__init__.py
[modify] https://crrev.com/a8d18a31ba11b7a62018326b3002e8278746ccda/bootstrap/deps.pyl
[modify] https://crrev.com/a8d18a31ba11b7a62018326b3002e8278746ccda/infra/libs/service_utils/outer_loop.py