tree 16a1c50f133b31f1740969f87624ae5c39b711ae
parent 5e022a386ba0432a4b90047a39788775655c9ab5
author Alex Vakulenko <avakulenko@chromium.org> 1429641803 -0700
committer ChromeOS Commit Bot <chromeos-commit-bot@chromium.org> 1429667177 +0000

buffet: Queue multiple command update requests to the server

When we update command data quickly (e.g. progress, status, results)
we issue multiple asynchronous PATCH requests to GCD server for the
same command resource which end up overwriting each other's data.

Now if a PATCH request is in flight to the server, another PATCH
request for the same command resource will not be sent until the
previous one completes (either successfully or with an error).

In meantime, command property updates accumulate and will be sent
out to the server in the next request batch.

BUG=brillo:821
TEST=`FEATURES=test emerge-link buffet`
     Deployed on device and tested with live GCD server.

Change-Id: I863a8b7689281e09017c8533f7613cef5681ff28
Reviewed-on: https://chromium-review.googlesource.com/266646
Trybot-Ready: Alex Vakulenko <avakulenko@chromium.org>
Tested-by: Alex Vakulenko <avakulenko@chromium.org>
Reviewed-by: Vitaly Buka <vitalybuka@chromium.org>
Commit-Queue: Alex Vakulenko <avakulenko@chromium.org>