ruoyi-vue-plus RepeatSubmit源码解读

RepeatSubmit作用

同一个用户的统一操作，在规定的时间内只能做一次相同数据的请求，防止重复提交，超时重试等一些问题

RepeatSubmit使用注意事项

查询和删除是天然的幂等操作，故一般不建议使用。在有更新和写入的操作时，建议使用，例如订单提交，修改订单状态。
幂等性: 多次执行的结果和一次执行成功的结果对资源的作用是相同的，这里的资源一般指的是数据库的数据。

使用

interval 间隔时间默认单位是ms message 为默认返回信息

@RepeatSubmit(interval = 10000,message = "不能重复提交")

ruoyi 脚手架的实现

使用拦截器 + 过滤器实现的

拦截器 : 对带有RepeatSubmit 接口进行重复性校验，将 ( key标识 + 请求url + base64（用户请求数据）) 作为key，时间戳 + 请求数据组成map 作为value，当然了 key 可以自行进行修改。
过滤器: 对请求进行过滤，将请求转化为可重复读取inputStream的request。

具体代码如下（本人已修改）:

package com.example.interceptor;import java.lang.annotation.*;/*** 自定义注解防止表单重复提交* 建议查询和删除不要使用此注解。* @author ruoyi**/
@Inherited
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface RepeatSubmit
{/*** 间隔时间(ms)，小于此时间视为重复提交*/public int interval() default 5000;/*** 提示消息*/public String message() default "不允许重复提交，请稍候再试";
}

定义拦截器

package com.example.interceptor;import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.lang.reflect.Method;/*** 防止重复提交拦截器** @author ruoyi*/
@Component
@Slf4j
public abstract class RepeatSubmitInterceptor implements HandlerInterceptor
{@Overridepublic boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception{if (handler instanceof HandlerMethod){HandlerMethod handlerMethod = (HandlerMethod) handler;Method method = handlerMethod.getMethod();RepeatSubmit annotation = method.getAnnotation(RepeatSubmit.class);if (annotation != null){if (this.isRepeatSubmit(request, annotation)){log.info("重复提交了!!!可自行定义返回格式");// 重复提交了
//                    AjaxResult ajaxResult = AjaxResult.error(annotation.message());
//                    ServletUtils.renderString(response, JSON.toJSONString(ajaxResult));return false;}}return true;}else{return true;}}/*** 验证是否重复提交由子类实现具体的防重复提交的规则** @param request 请求信息* @param annotation 防重复注解参数* @return 结果* @throws Exception*/public abstract boolean isRepeatSubmit(HttpServletRequest request, RepeatSubmit annotation);
}

具体实现机制
可自定义key

package com.example.interceptor.impl;import com.alibaba.fastjson2.JSON;import com.example.interceptor.RepeatSubmit;
import com.example.interceptor.RepeatSubmitInterceptor;
import com.example.interceptor.RepeatedlyRequestWrapper;
import com.example.util.redis.RedisCache;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import sun.misc.BASE64Encoder;import javax.servlet.ServletRequest;
import javax.servlet.http.HttpServletRequest;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.TimeUnit;/*** 判断请求url和数据是否和上一次相同，* 如果和上次相同，则是重复提交表单。 有效时间为10秒内。* * @author ruoyi*/
@Slf4j
@Component
public class SameUrlDataInterceptor extends RepeatSubmitInterceptor
{public final String REPEAT_PARAMS = "repeatParams";public final String REPEAT_TIME = "repeatTime";/*** 防重提交 redis key*/public final String REPEAT_SUBMIT_KEY = "repeat_submit:";// 令牌自定义标识@Value("${token.header}")private String header;@Autowiredprivate RedisCache redisCache;@SuppressWarnings("unchecked")@Overridepublic boolean isRepeatSubmit(HttpServletRequest request, RepeatSubmit annotation){BASE64Encoder encoder = new BASE64Encoder();String nowParams = "";if (request instanceof RepeatedlyRequestWrapper){// 注意 一定要使用过滤器 将 request 转换为 RepeatedlyRequestWrapper 不然无法获取请求参数RepeatedlyRequestWrapper repeatedlyRequest = (RepeatedlyRequestWrapper) request;nowParams = getBodyString(repeatedlyRequest);}// body参数为空，获取Parameter的数据  nowParamsif ("".equals(nowParams.trim())){nowParams = JSON.toJSONString(request.getParameterMap());}Map<String, Object> nowDataMap = new HashMap<String, Object>();nowDataMap.put(REPEAT_PARAMS, nowParams);nowDataMap.put(REPEAT_TIME, System.currentTimeMillis());// 请求地址（作为存放cache的key值）String url = request.getRequestURI();String str = request.getHeader(header);// 唯一值（没有消息头则使用请求地址）String submitKey =  str == null ? "" : str.trim();// 可以获取 不同的 IP地址 或者 mac地址 进行 主机识别  加上此注解的 通过id查询可能会受影响 所以建议查询和删除不要使用此注解即可。// 使用 BASE64 对 submitKey 和 请求数据 加密String dataEncryption = encoder.encode((submitKey+nowParams).getBytes(StandardCharsets.UTF_8));// 唯一标识（指定key + url + 请求数据 ）String cacheRepeatKey = REPEAT_SUBMIT_KEY + url + dataEncryption;Object sessionObj = redisCache.getCacheObject(cacheRepeatKey);// 判断 redis 中 有无重复的keyif (sessionObj != null){Map<String, Object> sessionMap = (Map<String, Object>) sessionObj;if (sessionMap.containsKey(url)){Map<String, Object> preDataMap = (Map<String, Object>) sessionMap.get(url);// 比较 请求参数    判断间隔时间 是否有效if (compareParams(nowDataMap, preDataMap) && compareTime(nowDataMap, preDataMap, annotation.interval())){return true;}}}Map<String, Object> cacheMap = new HashMap<String, Object>();cacheMap.put(url, nowDataMap);redisCache.setCacheObject(cacheRepeatKey, cacheMap, annotation.interval(), TimeUnit.MILLISECONDS);return false;}/*** 判断参数是否相同*/private boolean compareParams(Map<String, Object> nowMap, Map<String, Object> preMap){String nowParams = (String) nowMap.get(REPEAT_PARAMS);String preParams = (String) preMap.get(REPEAT_PARAMS);return nowParams.equals(preParams);}/*** 判断两次间隔时间*/private boolean compareTime(Map<String, Object> nowMap, Map<String, Object> preMap, int interval){long time1 = (Long) nowMap.get(REPEAT_TIME);long time2 = (Long) preMap.get(REPEAT_TIME);if ((time1 - time2) < interval){return true;}return false;}public String getBodyString(ServletRequest request){StringBuilder sb = new StringBuilder();BufferedReader reader = null;try (InputStream inputStream = request.getInputStream()){reader = new BufferedReader(new InputStreamReader(inputStream, StandardCharsets.UTF_8));String line = "";while ((line = reader.readLine()) != null){sb.append(line);}}catch (IOException e){log.warn("getBodyString出现问题！");}finally{if (reader != null){try{reader.close();}catch (IOException e){log.error("关闭文件错误");}}}return sb.toString();}
}

可重复读取inputStream的request

package com.example.interceptor;import lombok.extern.slf4j.Slf4j;import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import java.io.*;
import java.nio.charset.StandardCharsets;/*** 构建可重复读取inputStream的request* * @author ruoyi*/
@Slf4j
public class RepeatedlyRequestWrapper extends HttpServletRequestWrapper
{private final byte[] body;public RepeatedlyRequestWrapper(HttpServletRequest request, ServletResponse response) throws IOException{super(request);request.setCharacterEncoding("UTF-8");response.setCharacterEncoding("UTF-8");body = getBodyString(request).getBytes(StandardCharsets.UTF_8);}@Overridepublic BufferedReader getReader() throws IOException{return new BufferedReader(new InputStreamReader(getInputStream()));}@Overridepublic ServletInputStream getInputStream() throws IOException{final ByteArrayInputStream bais = new ByteArrayInputStream(body);return new ServletInputStream(){@Overridepublic int read() throws IOException{return bais.read();}@Overridepublic int available() throws IOException{return body.length;}@Overridepublic boolean isFinished(){return false;}@Overridepublic boolean isReady(){return false;}@Overridepublic void setReadListener(ReadListener readListener){}};}public String getBodyString(ServletRequest request){StringBuilder sb = new StringBuilder();BufferedReader reader = null;try (InputStream inputStream = request.getInputStream()){reader = new BufferedReader(new InputStreamReader(inputStream, StandardCharsets.UTF_8));String line = "";while ((line = reader.readLine()) != null){sb.append(line);}}catch (IOException e){log.warn("getBodyString出现问题！");}finally{if (reader != null){try{reader.close();}catch (IOException e){log.error("关闭文件错误");}}}return sb.toString();}
}

将拦截器注册进入系统配置中

package com.example.interceptor;import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.cors.CorsConfiguration;
import org.springframework.web.cors.UrlBasedCorsConfigurationSource;
import org.springframework.web.filter.CorsFilter;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;/*** 通用配置* * @author ruoyi*/
@Configuration
public class ResourcesConfig implements WebMvcConfigurer
{@Autowiredprivate RepeatSubmitInterceptor repeatSubmitInterceptor;/*** 自定义拦截规则*/@Overridepublic void addInterceptors(InterceptorRegistry registry){// 把重复校验添加到系统配置中// 重复校验拦截所有请求   自行判断是否重复校验 有注解则校验 没有则不校验registry.addInterceptor(repeatSubmitInterceptor).addPathPatterns("/**");}/*** 跨域配置*/@Beanpublic CorsFilter corsFilter(){CorsConfiguration config = new CorsConfiguration();config.setAllowCredentials(true);// 设置访问源地址config.addAllowedOriginPattern("*");// 设置访问源请求头config.addAllowedHeader("*");// 设置访问源请求方法config.addAllowedMethod("*");// 有效期 1800秒config.setMaxAge(1800L);// 添加映射路径，拦截一切请求UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();source.registerCorsConfiguration("/**", config);// 返回新的CorsFilterreturn new CorsFilter(source);}
}

定义过滤器

package com.example.filter;import com.example.interceptor.RepeatedlyRequestWrapper;
import org.springframework.http.MediaType;import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;/*** Repeatable 过滤器* * @author ruoyi*/
public class RepeatableFilter implements Filter
{@Overridepublic void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)throws IOException, ServletException{ServletRequest requestWrapper = null;if (request instanceof HttpServletRequest&& startsWithIgnoreCase(request.getContentType(), MediaType.APPLICATION_JSON_VALUE)){requestWrapper = new RepeatedlyRequestWrapper((HttpServletRequest) request, response);}if (null == requestWrapper){chain.doFilter(request, response);}else{chain.doFilter(requestWrapper, response);}}public static boolean startsWithIgnoreCase(CharSequence str, CharSequence prefix) {return startsWith(str, prefix);}private static boolean startsWith(CharSequence str, CharSequence prefix) {if (str != null && prefix != null) {int preLen = prefix.length();return preLen <= str.length() && regionMatches(str, prefix, preLen);} else {return str == prefix;}}static boolean regionMatches(CharSequence cs, CharSequence substring, int length) {if (cs instanceof String && substring instanceof String) {return ((String)cs).regionMatches(true, 0, (String)substring, 0, length);} else {int index1 = 0;int index2 = 0;int tmpLen = length;int srcLen = cs.length();int otherLen = substring.length();if (length >= 0) {if (srcLen >= length && otherLen >= length) {while(tmpLen-- > 0) {char c1 = cs.charAt(index1++);char c2 = substring.charAt(index2++);if (c1 != c2) {char u1 = Character.toUpperCase(c1);char u2 = Character.toUpperCase(c2);if (u1 != u2 && Character.toLowerCase(u1) != Character.toLowerCase(u2)) {return false;}}}return true;} else {return false;}} else {return false;}}}
}

将过滤器注册进入系统中

package com.example.filter;import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;/*** Filter配置** @author ruoyi*/
@Configuration
public class FilterConfig
{@SuppressWarnings({ "rawtypes", "unchecked" })@Beanpublic FilterRegistrationBean someFilterRegistration(){FilterRegistrationBean registration = new FilterRegistrationBean();registration.setFilter(new RepeatableFilter());registration.addUrlPatterns("/*");registration.setName("repeatableFilter");registration.setOrder(FilterRegistrationBean.LOWEST_PRECEDENCE);return registration;}
}