Merge pull request #246013 from dominicbetts/central-cde-api-updates

IoT Central: Add detail to CDE API doc

Author: prmerger-automator[bot]

articles/iot-central/core/howto-manage-data-export-with-rest-api.md

@@ -233,6 +233,95 @@ The response to this request looks like the following example:
 }
 ```
 
+#### Enrichments
+
+There are three types of enrichment that you can add to an export: custom strings, system properties, and custom properties:
+
+The following example shows how to use the `enrichments` node to add a custom string to the outgoing message:
+
+```json
+"enrichments": {
+  "My custom string": {
+    "value": "My value"
+  },
+  //...
+}
+```
+
+The following example shows how to use the `enrichments` node to add a system property to the outgoing message:
+
+```json
+"enrichments": {
+  "Device template": {
+    "path": "$templateDisplayName"
+  },
+  //...
+}
+```
+
+You can add the following system properties:
+
+| Property | Description |
+| -------- | ----------- |
+| `$enabled` | Is the device enabled? |
+| `$displayName` | The device name. |
+| `$templateDisplayName` | The device template name. |
+| `$organizations` | The organizations the device belongs to. |
+| `$provisioned` | Is the device provisioned? |
+| `$simulated` | Is the device simulated? |
+
+The following example shows how to use the `enrichments` node to add a custom property to the outgoing message. Custom properties are properties defined in the device template the device is associated with:
+
+```json
+"enrichments": {
+  "Device model": {
+    "target": "dtmi:azure:DeviceManagement:DeviceInformation;1",
+    "path": "model"
+  },
+  //...
+}
+```
+
+#### Filters
+
+You can filter the exported messages based on telemetry or property values.
+
+The following example shows how to use the `filter` field to export only messages where the accelerometer-X telemetry value is greater than 0:
+
+```json
+{
+  "id": "export-001",
+  "displayName": "Enriched Export",
+  "enabled": true,
+  "source": "telemetry",
+  "filter": "SELECT * FROM dtmi:azurertos:devkit:gsgmxchip;1 WHERE accelerometerX > 0",
+  "destinations": [
+    {
+      "id": "dest-001"
+    }
+  ],
+  "status": "healthy"
+}
+```
+
+The following example shows how to use the `filter` field to export only messages where the `temperature` telemetry value is greater than the `targetTemperature` property:
+
+```json
+{
+  "id": "export-001",
+  "displayName": "Enriched Export",
+  "enabled": true,
+  "source": "telemetry",
+  "filter": "SELECT * FROM dtmi:azurertos:devkit:gsgmxchip;1 AS A, dtmi:contoso:Thermostat;1 WHERE A.temperature > targetTemperature",
+  "destinations": [
+    {
+      "id": "dest-001"
+    }
+  ],
+  "status": "healthy"
+}
+```
+
 ### Get an export by ID
 
 Use the following request to retrieve details of an export definition from your application: