Overview
This component allows generating unique alarms. You are able to specify alarm ID and alarm body templates. Template evaluation is based on velocity engine. When component process incoming device messages it substitutes message values and device attributes into template. Alarm uniqueness is controlled by result value of alarm ID. If processor detects unique alarm, it will add following metadata:
- isNewAlarm boolean flag to true.
- alarmId string.
- alarmBody string.
Configuration
Template evaluation is done using certain context. This context is populated with values based on device message and attributes. Attribute values are available using maps with following names:
- cs - client-side attributes map.
- ss - server-side attributes map.
- shared - shared attributes map.
Telemetry values are pushed directly to the context using their keys. You can also use date, deviceId, deviceName, and deviceType.
For example, following template:
1
[$date.get('yyyy-MM-dd HH:mm:ss')] Device $deviceType+$cs.get('serialNumber')($cs.get('model')) temperature is $temperature.valueAsString!
Will be evaluated into
1
[2016-01-02 03:04:05] Device Killbot4000+SN-001(A) temperature is 100!
for Device with
- client-side attribute serial number = SN-001
- client-side attribute model = A
and telemetry message
1
{"temperature":100}
We recommend to include the truncated date and some unique device attribute into alarm id template. This will ensure that you will not generate alarms for the same device problem too often.
Example
As a tenant administrator, you are able to review processor example inside Rules->Demo Alarm Rule->Processors->Alarm Deduplication Processor.
