If you do not use the standard Customer or Product picker but you create your own api.product() or api.customer() picker, you must explicitly retrieve the product or customer list – it is not done automatically.

The following example shows how to populate Customer input from a header logic:

cProcessor.addOrUpdateInput("ROOT", ["name": "CustomerGroup", "label": "Customer(s)", "type": InputType.CUSTOMERGROUP, "value": [
            "customerFieldLabel": "Unique Customer Id",
            "customerFieldName" : "customerId",
            "customerFieldValue": customerId
    ]])