Background:
I am trying to get my endpoint URL from HttpContext for attribute validation work where the URL needed to be fully identical. The problem happens when I try the get the full URL, where the scheme will always be http instead of https.
During testing using Postman, my GET URL is https.
e.g https://endpoint/id?access_token=xxx

Code sample:

   public ProofKeyContextFactory Create(HttpContext httpContext)
   {
    var endpointUrl = httpContext.Request
            .GetDisplayUrl()
            .ToUpperInvariant();
    _logger.LogInformation("Endpoint URL: {EndpointUrl}", endpointUrl);
   }

When I check log, the endpoint will be HTTP://ENDPOINT/ID?ACCESS_TOKEN=XXX instead with HTTPS.

I tried using httpContext.Request.Scheme but still returning https

What cause the SSL scheme to be terminated?