public static Mono<Void> noRuleResult(final String pluginName, final ServerWebExchange exchange) {
        LOG.error("can not match rule data: {} , path is {}", pluginName, exchange.getRequest().getURI().getRawPath());
        Object error = ShenyuResultWrap.error(exchange, ShenyuResultEnum.RULE_NOT_FOUND.getCode(), pluginName + ":" + ShenyuResultEnum.RULE_NOT_FOUND.getMsg(), null);
        return WebFluxResultUtils.result(exchange, error);
    }
get no rule result.

@param pluginName the plugin name
@param exchange   the exchange
@return the mono
shenyu-plugin/shenyu-plugin-api/src/main/java/org/apache/shenyu/plugin/api/utils/WebFluxResultUtils.java