Support for Access-Control-Allow-Private-Network

[timothy-s-dev]

Feature Request

Motivation

Chrome is removing/has removed the ability to send requests to private network endpoints from public websites:
https://developer.chrome.com/blog/private-network-access-preflight/

There is a pre-flight header it sends now (Access-Control-Request-Private-Network) and expects in the response to allow those requests through.

Proposal

Perhaps a new method alongside allow_headers/allow_methods/etc on CorsLayer (allow_private_network_access?) that provides the correct response header for the preflight request?

[jplatte]

Help is still wanted, #315 is complete as far as the main logic is concerned, but is missing tests and I don't want to dedicate more time to it (I don't actually have a use case for this myself).

[jplatte]

Done in #373.