[erlang-questions] [ANN] Elarm (Erlang alarm library)

[Csaba Hoch]

Hi,

I would like to announce a new Erlang alarm library called Elarm
(https://github.com/esl/elarm).

Elarm is an Alarm Manager for Erlang. It is designed to be easy to
include in an Erlang based system and easy to use:

   ok = elarm:raise(partition_full, "/dev/hda2", [{level,90}])  # raise an alarm
   ok = elarm:clear(partition_full, "/dev/hda2")                # clear the alarm

Elarm stores the alarms on the node (in ets by default, but the
backend can be changed). This makes it easier for the node to have a
REST/SNMP/web/etc. interface that shows the node's alarms, since those
interfaces can ask Elarm for the list of alarms, which will include
the alarm state (new or acknowledged), severity, and quite a few other
fields:

    -record(alarm, {
              alarm_id                                :: alarm_id(),   % e.g. 'partition_full'
              alarm_type                              :: alarm_type(), % e.g. 'environment'
              src                                     :: alarm_src(),  % e.g. "/dev/hda2"
              event_time = calendar:universal_time()  :: timestamp(),
              event_id                                :: event_id(),
              severity = indeterminate                :: severity(),
              probable_cause = <<"">>                 :: probable_cause(),
              proposed_repair_action = <<"">>         :: proposed_repair_action(),
              description = <<"">>                    :: description(),
              additional_information                  :: additional_information(), % e.g. [{level,90}]
              correlated_events = []                  :: [event_id()], % not used yet
              comments = []                           :: comments(),
              trend                                   :: trend(), % not used yet
              threshold                               :: undefined | threshold(), % not used yet
              state = new                             :: alarm_state(),
              ack_info                                :: ack_info()
             }).

The alarm_type, severity, probable_cause, proposed_repair_action and
description fields can be filled in by the alarm configuration. (I.e.
the developer or operator can say in advance that the
partition_full+"/dev/hda2" alarm should have 'environment' alarm type,
'major' severity, etc.)

The code is available on GitHub, together with the README that
describes the further features (including acknowledging and commenting
alarms, and subscribing to them): https://github.com/esl/elarm

We hope that Elarm becomes the de facto alarming application in the
Erlang world and we will certainly do all we can to make it as good as
possible.

Elarm is in part funded by the RELEASE project
(http://release-project.eu/), which is an EU FP7 STREP (287510)
project that aims to scale the radical concurrency-oriented
programming paradigm to build reliable general-purpose software, such
as server-based systems, on massively parallel machines.

Regards,
Csaba