You can answer to a waiting user interaction of a workflow run by using the Orchestrator REST API.


Verify that you have imported the sample workflows package in Orchestrator. The package is included in the Orchestrator sample applications ZIP file that you can download from the Orchestrator documentation page.


  1. Retrieve the list of all user interaction objects by making a GET request at the URL that holds the available user interaction objects, or by filtering only the waiting user interactions:
    URL Description
    https://orchestrator_host:port/vco/api/catalog/System/UserInteraction Holds the available user interaction objects in Orchestrator
    https://orchestrator_host:port/vco/api/catalog/System/UserInteraction?status=0 Filters only the waiting user interaction objects.
    You receive a list of the available user interaction objects. User interactions that are waiting have an attribute with name state and value waiting.
  2. Make a GET request at the URL that holds the inventory item of the waiting user interaction to which you want to answer:
    GET https://{orchestrator_host}:{port}/vco/api/catalog/System/UserInteraction/{userInteractionID}/
    The inventory item contains a link to the user interaction instance.The user interaction instance is associated with a particular workflow run.
  3. Make a POST request at the URL of the user interaction instance for the particular workflow execution:
    POST https://{orchestrator_host}:{port}/vco/api/workflows/{workflowID}/executions/{executionID}/interaction/
  4. Provide values for the input parameters of the user interaction in an execution-context element in the request body.


The REST API returns a 204 status when you answer to a user interaction successfully.

Example: Answer to the User Interaction of the Interactive Hello World Workflow

You can run the Interactive Hello World sample workflow and answer to its user interaction.

  1. Search for the waiting user interaction of the workflow by making GET request at the endpoint for the user interaction objects of the Catalog service:
    GET https://localhost:8281/vco/api/catalog/System/UserInteraction?status=0
  2. Locate the user interaction inventory object for the Interactive Hello World workflow and make a GET request at its URL:
    GET https://localhost:8281/vco/api/catalog/System/UserInteraction/888080808080808080808080808080805A8080800132145338690643f66a027ec/
  3. Make a POST request at the URL of the user interation objects for the currently running workflow execution:
    POST https://localhost:8281/vco/api/workflows/CF808080808080808080808080808080E6808080013086668236014a0614d16e1/executions/88808080808080808080808080808080578080800132145338690643f66a027ec/interaction/

    Provide a value for the input parameter in the request body:

    <execution-context xmlns="">
         <parameter name="name" type="string">
           <string>John Smith</string>