in functions.go [87:95]
func writeError(l *zap.SugaredLogger, res http.ResponseWriter, code int, s string) {
l.Errorw(s, "code", code)
res.Header().Add("Content-Type", "text/plain")
res.WriteHeader(code)
_, err := io.WriteString(res, s)
if err != nil {
l.Errorw("WriteString failed", "error", err)
}
}