2583.Bugfix

Due to the differences in interpretation of the ASGI specification, Uvicorn could set client in the HTTP connection scope in a way that broke :attr:req.access_route <falcon.asgi.Request.access_route> and :attr:req.remote_addr <falcon.asgi.Request.remote_addr> when the app server was bound to a Unix domain socket.

This discrepancy was addressed, and Falcon should now fall back to the same default value ('127.0.0.1') in this case as if client was missing altogether.