/// <summary>
/// The user name.
/// </summary>
/// <param name="userId">
/// The user id.
/// </param>
/// <returns>
/// The <see cref="string"/>.
/// </returns>
public string UserName(string userId)
{
var handler = new UserInfoHandler(StfLogger, WtApiConfiguration);
var userInfo = handler.UserInfoById(userId);
var retVal = userInfo?.UserName ?? "Unknown userId";
return(retVal);
}