.NET SDK Used Behind a Reverse Proxy (NGINX) Uses Incorrect Callback URL

This article explains why when an application is hosted behind a reverse proxy, the redirect_uri generated on the /authorize appears to be http://127.0.0.1:5000/callback. The desired behavior is that the domain should represent the domain of the application where the /authorize call was initiated.

• .NET SDK
• Reverse Proxy
• NGINX
• Callback URL
• Redirect URI

This is likely a configuration issue on the reverse proxy / forward header side.

• Review the following documentation for potential solutions:
  • Configure ASP.NET Core to work with proxy servers and load balancers
  • Configure Nginx

The reverse proxy misconfiguration may be causing Request.Host to show 127.0.0.1 , and Request.Scheme  to show  http.

• Solutions for both sides need to be sought, i.e., the reverse proxy (NGINX) AND ASP.NET, not just the reverse proxy.
• See this FAQ for more information: 
  • Reverse Proxy