I created a FastAPI app and I can access the Swagger UI autodocs at https://cloudrundomain.app/docs. When I send an HTTPS request using the Swagger UI, the request.headers.get("X-Forwarded-Proto") is HTTPS, but the request.url is http://cloudrundomain (the bottom of my problem is that HTTPException is HTTP, but I think it starts there).

I don’t think it’s a good idea, but I tried doing what you could see below. The “Modify the scheme to HTTPS to avoid mixed content issues” triggers, but the redirection then fails.

@app.middleware("http")
async def force_https(request: Request, call_next):
   # Check the X-Forwarded-Proto header to determine if the request is HTTP
   forwarded_proto = request.headers.get("X-Forwarded-Proto")

   if forwarded_proto == "http":
       print("Redirect to HTTPS")
       return RedirectResponse(url=f"https://{request.url.hostname}{request.url.path}")

   # Ensure URLs are constructed using HTTPS
   # Modify request.url to use HTTPS if necessary
   if forwarded_proto == "https" and request.url.scheme == "http":
       print("Modify the scheme to HTTPS to avoid mixed content issues")
       return RedirectResponse(url=f"https://{request.url.hostname}{request.url.path}")

   # Proceed with the request if it's already HTTPS or after the redirect
   response = await call_next(request)
   return response