Gerrit Trigger Plugin Listener allows to subscribe on each build started / validation completed event.

If listener received change related event (i.e. PatchsetCreated) for onCompleted (this event is triggered in the moment when Gerrit Trigger Plugin pushes the vote to the change) it will push to FluentD this data:
Field nameExample
resultABORTED
event_typepatchset-created
command_size33
owner_namename
owner_emailemail
change_idchange
projectproject_name
topictopic_name
branchbranch_name
patchset_numbernumber
patchset_kindTRIVIAL_REBASE
change_created_on1507274800000
patchset_created_on1507274900000
event_created_on1507275000000
For onStarted (this event is triggered in the moment when Gerrit Trigger Plugin sends information that builds started) it will push the same data except result field.

In case of not a change related changes (i.e. RefUpdated) only command and result will be sent. But it should never happen according the current implementation of GerritTriggerPlugin

The data for onStarted is pushed with tag gerrit_trigger_plugin.on_started. The onCompleted goes to gerrit_trigger_plugin.on_completed.