This is Callback API sample for WorkflowServer.

Users list:
{"name":"User1","userId":"User1","roles":["User","Manager","Accountant"]}
{"name":"User2","userId":"User2","roles":["User","Manager"]}
{"name":"User3","userId":"User3","roles":["User","Supervisor"]}
{"name":"User4","userId":"User4","roles":["User"]}


Source code: https://codesandbox.io/s/workflowservercallbackapi-57zb8