diff --git a/modules/caddyhttp/caddyhttp.go b/modules/caddyhttp/caddyhttp.go index 576620eb..24121c10 100644 --- a/modules/caddyhttp/caddyhttp.go +++ b/modules/caddyhttp/caddyhttp.go @@ -322,22 +322,27 @@ func (app *App) Stop() error { return err } } - // TODO: Closing the http3.Server is the right thing to do, - // however, doing so sometimes causes connections from clients - // to fail after config reloads due to a bug that is yet - // unsolved: https://github.com/caddyserver/caddy/pull/2727 - // for _, s := range app.h3servers { - // // TODO: CloseGracefully, once implemented upstream - // // (see https://github.com/lucas-clemente/quic-go/issues/2103) - // err := s.Close() - // if err != nil { - // return err - // } - // } - // as of September 2019, closing the http3.Server - // instances doesn't close their underlying listeners - // so we have todo that ourselves - // (see https://github.com/lucas-clemente/quic-go/issues/2103) + + // close the http3 servers; it's unclear whether the bug reported in + // https://github.com/caddyserver/caddy/pull/2727#issuecomment-526856566 + // was ever truly fixed, since it seemed racey/nondeterministic; but + // recent tests in 2020 were unable to replicate the issue again after + // repeated attempts (the bug manifested after a config reload; i.e. + // reusing a http3 server or listener was problematic), but it seems + // to be working fine now + for _, s := range app.h3servers { + // TODO: CloseGracefully, once implemented upstream + // (see https://github.com/lucas-clemente/quic-go/issues/2103) + err := s.Close() + if err != nil { + return err + } + } + + // closing an http3.Server does not close their underlying listeners + // since apparently the listener can be used both by servers and + // clients at the same time; so we need to manually call Close() + // on the underlying h3 listeners (see lucas-clemente/quic-go#2103) for _, pc := range app.h3listeners { err := pc.Close() if err != nil {