JsonExportSetpointHandler (Json Export Setpoint Handler)

This component allows an external JSON message to change the value of a control point identified by the ID property of an export marker.

Locating target points like this can support a station where a unique key registers the points from the cloud platform. Once the cloud platform returns a suitable identifier for an export-marked point, you can use this setpoint handler to apply write messages from the platform using the ID, rather than the Niagara slot or handle ord (for example).

Figure 71.   JsonExportSetpointHandler properties
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To add this handler to a station, expand the ExportMarker folder in the palette and drag this component to the router folder in the Nav tree.

In addition to the standard property (Enabled), these properties support the JsonExportSetpointHandler.

Property Value Description
Last Result read-only Reports the results of the alarm acknowledgment to allow for logging or post-processing activity. Example output:

Unable to find messagge key:

Problem parsing messageType

Last Result Time read-only Reports when the handler ran last.
Last Input read-only Reports the last JSON string input, which was routed through this component. This string either successfully altered a setpoint or failed as indicated by the Status property.
Id Key text Defines which top-level key in the JSON payload represents the point Id.
Value Key text (defaults to value) Defines which top-level key in the JSON payload represents the value to set.
Slot Name Key text (defaults to slotName) Defines the optional top-level key in the JSON payload that represents the slot name to write to.
Default Write Slot (JsonExportSetpointHandler, SetPointHandler) text Defines the slot to write to by default if the payload does not specify the slot.