How to get current Workflow XML for active Instance by the Rest API

In my AngularApp i will show the User the current Workflow, by using the REST API. No Problem so far, usnig:

GET /process-definition/{id}/xml

and the

bpmn.io Viewer.

But it's possible to highlight the current Task or get the special Instance of the Workflow, with highlight the current Task?

Thank you for your help.

Solution

1. Get actual the task

The call http://localhost:8080/engine-rest/task/?processInstanceId=<processInstanceId> return a json with the taskDefinitionKey.

You can add a style class and so highlight a task.

viewer.importXML(diagramXML, function() {
    var canvas = viewer.get('canvas');
    canvas.addMarker('<<TaskId>>', 'highlight');
});

CSS for the color:

.highlight:not(.djs-connection) .djs-visual > :nth-child(1) {
    fill: green !important; /* color elements as green */
}