TelemetryItem
A telemetry item is a sub-type of a RelatedItem. It represents a telemetry item in the Item Service, such as a device sensor.
A telemetry item has the same characteristics as a RelatedItem but also has a "_sourceId" property to identify the data sensor source readings. For more information, see the following code example with reference to the schema:
{ "_id": "f3e36c5e-5d9f-4d5d-a692-b25ce180438b", "_sourceId": "a2e052a6-9126-21d5-7301-0000863f27ad-3450121", // The source's id}| Parameter | Type | Description | Required |
|---|---|---|---|
_id | String | The TelemetryItem's ID | Required |
_sourceId | String | The ID of an external source, device, sensor, or point on a sensor that generates the time series data. | Required |
Custom properties#
Like a RelatedItem, you can add your own properties:
{ "_id": "f3e36c5e-5d9f-4d5d-a692-b25ce180438b", "_sourceId": "a2e052a6-9126-21d5-7301-0000863f27ad-3450121", "name": "your sensor's name", // Custom property "description": "a description of your sensor", // Custom property "dtType": "The asset type", // Custom property "floorname": "The asset's floor", // Custom property "roomname": "The asset's room", // Custom property}Readings#
Readings are timeseries items stored in the database that contain timestamped recordings from the data source.
{ { "_ts": "2022-07-02T05:15:30+05:30", "_tsMetadata": { "_telItemId": "62befda2c21eca157f108e22", "_sourceId": "a2e052a6-9126-21d5-7301-0000863f27ad-3450121" } }, { "_ts": "2022-07-02T05:20:35+06:30", "_tsMetadata": { "_telItemId": "62befda2c21eca157f108e22", "_sourceId": "a2e052a6-9126-21d5-7301-0000863f27ad-3450121" } }}| Parameter | Type | Description | Required |
|---|---|---|---|
_ts | String | The reading's timestamp. | Required |
_tsMetadata | Object | An object that contains the timestamp's metadata, such as the TelemetryItem's ID and the source ID | Required |
_tsMetadata._telItemId | String | The ID of the TelemetryItem that recorded the reading. | Required |
_tsMetadata._sourceId | String | The ID of the TelemetryItem's source that recorded the reading | Required |
Readings custom attributes#
You can add custom attributes to a reading. The following example includes value and unit properties to store temperature recordings.
{ { "_ts": "2022-07-02T05:15:30+05:30", "_tsMetadata": { "_telItemId": "62befda2c21eca157f108e22", "_sourceId": "a2e052a6-9126-21d5-7301-0000863f27ad-3450121" }, "value": "23.2", // Custom property "unit": "degC" // Custom property }}Collection#
Store TelemetryItems in a NamedTelemetryCollection. When your TelemetryItems are in a collection, you can create relationships between them and items in the same or other collection.
API#
You can create and manage telemetry items using the IafItemSvc JavaScript Platform API or the Item Service REST API.