Domorela's Blog: Domorela's REST API: Alarm Service

Alarm Service allows for query and acknowledge alarms fired by Domorela to any system capable to send a REST query. Thus is possible to query to obtain a partial or complete list of fired alarms, obtain their state and acknowledge them.

The current version of Domorela works with boolean alarms that have a correspondence with boolean alarms defined in the KNX installation. This way, by configuring as an Alarm Object a Datapoint or Group Address identifying a Communication Object acting as boolean alarm, that is, announcing if the alarm is fired or not, the Alarm Service of Domorela records it as an alarm object and starts notifications about this new alarm object.

Current alarms in Domorela can have two states: active and acknowledged, and the Alarm Service of the API allows for query and acknowledge any alarm, that must be cleared to be deleted from the current list of active and acknowledged alarms.

In order to send a query, there is needed to include a time filter in this query. The filter must include both an start and an end absolute time values to catch all the active alarms for this time interval. In order to acknowledge an alarm, is necessary to include the value of the URI for the alarm wanted to be acknowledged.

So the normal behaviour is to first query to know active alarms since last query then acknowledge all the active alarms we think must be acknowledged. Due to security reasons, the only way to clear alarms is through the Domorela's WUI, by going to any of the views where the alarm object appears, usually in the Alarms View, and putting it off.

To give a solution for any alarm is out of the scope of this article, as it can depend of many types of factors and could require many types of actions that probably need to be performed by humans handling other devices. If any of the actions taken to solve the problem that generated the alarm event results in a new event that changes the state of the alarm Communication Object, then the corresponding Datapoint present in Domorela's configuration will change their state and the corresponding alarm object will be cleared.

To delete any Alarm Object from the Alarm Service in order to avoid it can be fired again, administrators must change the configuration of the alarm object. That is, must reset the alarm contract assigned to the object in the Configuration View.

Next article will speak about AAA service of Domorela's API.