"Upgrade",
}

func (p *ReverseProxy) defaultErrorHandler(rw http.ResponseWriter, req *http.Request, err error) {
	p.logf("http: proxy error: %v", err)
	rw.WriteHeader(http.StatusBadGateway)
}

func (p *ReverseProxy) getErrorHandler() func(http.ResponseWriter, *http.Request, error) {
	if p.ErrorHandler != nil {
		return p.ErrorHandler
	}
	return p.defaultErrorHandler
}