if authType == prometheusPublic {
		authFn = NoAuthMiddleware
	}

	metricGroups := newMetricGroups(registry)

	return &metricsV3Server{
		registry: registry,
		opts: promhttp.HandlerOpts{
			ErrorLog:            promLogger{},
			ErrorHandling:       promhttp.HTTPErrorOnError,
			Registry:            registry,
			MaxRequestsInFlight: 2,
		},
		authFn: authFn,

		metricsData: metricGroups,
	}
}

		return ctx
	}
	return srv
}

// UseCustomLogger use customized logger for this HTTP *Server
func (srv *Server) UseCustomLogger(l *log.Logger) *Server {
	srv.ErrorLog = l
	return srv
}

// UseTCPOptions use custom TCP options on raw socket
func (srv *Server) UseTCPOptions(opts TCPOptions) *Server {
	srv.TCPOptions = opts
	return srv
}

	// This splitter will fail on last entry, after s.err==EOF.
	split := func(data []byte, atEOF bool) (advance int, token []byte, err error) {
		advance, token, err = ScanWords(data, atEOF)
		if len(token) > 1 {
			if s.ErrOrEOF() != io.EOF {
				t.Fatal("not testing EOF")
			}
			err = testError
		}
		return
	}
	s.Split(split)
	for s.Scan() {
	}
	if s.Err() != testError {
		t.Fatal("wrong error:", s.Err())
	}

	if n < utf8.UTFMax || n > 1e9 {
		panic("bad max token size")
	}
	if n < len(s.buf) {
		s.buf = make([]byte, n)
	}
	s.maxTokenSize = n
}

// ErrOrEOF is like Err, but returns EOF. Used to test a corner case.
func (s *Scanner) ErrOrEOF() error {
	return s.err