You create custom property definitions that run vRealize Orchestrator actions to retrieve key value pairs from external files or from vRealize Automation configuration information. You add the custom properties to blueprints so that they appear in the catalog request forms.
The service catalog user requesting the item can select a value to include in the deployment. When the user clicks the drop-down menu to select a value, the vRealize Orchestrator action runs, retrieving the data that is displayed in the menu for the user to select.
The configuration workflows for each vRealize Orchestrator actions property definition are similar, but some of the details vary. For example, there are differences in prerequisites and limitations, and where you apply the custom property in the blueprint might vary.