How to get route data from Identity Server 4 endpoints - asp.net-core

Question

I have a ResponseTimeMiddleware.cs responsible for getting response time metrics (I am using datadog) for every request made. Which is tagged by controller and action names. However when we hit the "connect/token" endpoint, the context.GetRouteData() is null, probably because identity server is doing it behind the scenes. Is there a way I could get this information or some other unique information where I could tag with?
here's my code:
public class ResponseTimeMiddleware
{
// other code..
public Task InvokeAsync(HttpContext context)
{
var request = context.Request;
var watch = new System.Diagnostics.Stopwatch();
watch.Start();
context.Response.OnStarting(() =>
{
watch.Stop();
var routeData = context.GetRouteData();
var responseTime = watch.ElapsedMilliseconds.ToString();
var tags = new[] { $"statusCode:{context.Response.StatusCode.ToString()}", $"controller:{routeData.Values["controller"]}", $"action:{routeData.Values["action"]}" };
context.Response.Headers[ResponseHeaderResponseTime] = responseTime;
DogStatsd.Timer("response.time", responseTime, tags: tags);
return Task.CompletedTask;
});
return nextDelegate(context);
}
}
This is my Startup:
public class Startup
{
// other code..
public static void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
else
{
app.UseExceptionHandler("/Error");
app.UseHsts();
}
app.UseMiddleware<ResponseTimeMiddleware>();
app.UseMvcWithDefaultRoute();
app.UseStaticFiles();
app.UseEndpointRouting();
app.UseCookiePolicy();
app.UseCors("CorsPolicy");
app.UseIdentityServer();
// This method gets called by the runtime. Use this method to add services to the container.
public async void ConfigureServices(IServiceCollection services)
{
services.AddDataDogStatsd(Configuration, "identity");
// other code
}
}

Answer 1

Use context.Request.Path conditionally if your routeData is null. It is the closest I can think of since Identity Server 4 middleware has internal routing logic for the standard OAuth protocol routes.