http3 - when closing, http3.Server.Serve returns quic.ErrServerClosed instead of http.ErrServerClosed

[kgersen]

The returned error for http3.Server.Serve(...) is quic.ErrServerClosed in case of a normal shutdown/close.
It should be http.ErrServerClosed instead.
see method serveConn (some return paths already use http.ErrServerClosed).

[marten-seemann]

Is that incorrect? You can have a closed QUIC server, while the HTTP/3 server is still running.

[kgersen]

what is a "QUIC server" when working at HTTP/3 api level ? Do we need to know about such 'quic' stuff at this level ?
The http3 package tries to reproduce the same API as the net/http package.

With net/http, when we use ListenAndServeTLS or just ServeTLS and the call ends, it means the server stopped. As per the documentation:

ServeTLS always returns a non-nil error. After Shutdown or Close, the returned error is ErrServerClosed.
source: https://pkg.go.dev/net/http#Server.ServeTLS

So when http3.Server.Serve(...) ends, if the returned error is quic.ErrServerClosed what is the meaning of this ?

If we have existing code that use net/http and check for http.ErrServerClosed, when we switch or add http/3 we must add a special case to check for quic.ErrServerClosed which is confusing (which is what we're currently doing now).

[marten-seemann]

Should we replace the error if s.closed == true?

[kgersen]

Should we replace the error if s.closed == true?

no that's the only place where it is correct.

other return paths should be changed.