Get all registered routes in ASP.NET Core 1.1 application

Question

On an ASP.NET Core 1.1 application I need to get all registered routes so in a controller action I have:

public IActionResult GetAllRoutes() {          
  var routes = this.RouteData.DataTokens;
  return Ok(routes);
}

This seems to only return parameters of the current route. I also tried:

public IActionResult GetAllRoutes() {    
  var routes = RouteData.Routers.OfType<RouteCollection>();
  return Ok(routes);
}

This seems to only return the current route ...

Any idea how to get all registered routes in an ASP.NET Core application?