VSTS Dashboard Widget getWorkItem optional parameter expand

Question

I am writing a VSTS dashboard widget used for Work Item Tracking

However I am running into a problem when using the getWorkItem() function. I want to get the ids of all the Features under a given Epic (I already know the epic ID). I am confident that if I set the expand paremeter of getWorkItem() to "All" I will get a list of all the Features and their respective ids. Unfortunately I do not know how to define the "type" of expand parameter and how to properly pass it as a value to the getWorkItem() function.

Here is my code:

VSS.require(["VSS/Service", "TFS/Dashboards/WidgetHelpers", "TFS/WorkItemTracking/RestClient"],
        function (VSS_Service, WidgetHelpers, TFS_Wit_WebApi) {
            WidgetHelpers.IncludeWidgetStyles();
            VSS.register("myapp", function () {
                var fetchData = function (widgetSettings) {
                    const epicID = 123456;
                    // Get a WIT client to make REST calls to VSTS
                    return VSS_Service.getCollectionClient(TFS_Wit_WebApi.WorkItemTrackingHttpClient).getWorkItem(123456, null, null, All).
                        then(
                            //Successful retrieval of workItems
                            function (workItems) {
                                $('#myText').text(JSON.stringify(workItems));
                                console.log(workItems);
                                // Use the widget helper and return success as Widget Status
                                return WidgetHelpers.WidgetStatusHelper.Success();
                            },
                            function (error) {
                                // Use the widget helper and return failure as Widget Status
                                return WidgetHelpers.WidgetStatusHelper.Failure(error.message);
                            });
                }

Here is the VSTS reference for expand It explains what the values can be, but doesn't say how to pass it into the getWorkItem() function.

I would like to set the optional expand parameter of the function to "All" but don't know its type and how to properly define and use it.

Answer 1

Based on the source code, it is the enum, so you can specify the integer (e.g. 4) in getWorkItem function.

export enum WorkItemExpand {
    None = 0,
    Relations = 1,
    Fields = 2,
    Links = 3,
    All = 4,
}