4.4 Examples: Streaming Alarms, Alerts, and Annotations
|For Standard||ETPW20 v1|
P1 can also be used to stream notifications about operations in separate channels. Data consumers subscribe to alarms, alerts, and annotations in essentially the same way as they do to streaming any other data object as described in the ETP Specification.
We define these three categories of information:
- Alarm: notification that an incident requiring immediate attention is happening now.
- Alert: notification that an incident could happen or is imminent (e.g., an alert of an impending storm).
- Annotation: additional notation or description that may be interesting or helpful.
To implement these notifications:
- The alarm and alert channels use the DataItem.ValueAttributes dictionary to include additional metadata to further describe those events.
- Each example shows the required data items, though additional ones can be used.
- Currently, no pre-defined alarm or alert content types or enumerations are specified, so they cannot be auto-discovered.
- Alarm and alert channels must be configured and communicated during data mapping discussions between service providers and data aggregators.
- This capability is a direct replacement for the Message object from previous versions of WITSML.
The examples use a time-based index and string data values containing the descriptions for the alarms, alerts, and annotations. You can specify additional indexes, such as measured depth, as needed.