防止表单重复提交

一、前端控制（页面控制）

从前端控制主要方法就是点击提交后将提交按钮置灰，js中的提交方法不再响应提交事件

二、后端控制（接口控制）

自定义防止重复提交的注解
1.自定义注解@RepeatSubmit

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface RepeatSubmit {

    /**
     * 延迟时间
     * redis缓存时间
     *
     * @return
     */
    int delay() default 2;

    /**
     * 标识接口
     * 防止不同接口产生相同的key
     *
     * @return
     *String module();
     */
}

2. 注解相关的拦截器RepeatSubmitInterceptor

@Slf4j
public class RepeatSubmitInterceptor extends HandlerInterceptorAdapter {

    @Autowired
    private RedisUtil redisUtil;

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        if (request.getMethod().toUpperCase().equals("OPTIONS")) {
            return true;
        }
        if (!isRepeatSubmit(request, handler)) {
            return false;
        }

        return true;
    }

    private boolean isRepeatSubmit(HttpServletRequest request, Object handler) {
        if (!(handler instanceof HandlerMethod)) {
            return true;
        }
        HandlerMethod handlerMethod = (HandlerMethod) handler;
        Method method = handlerMethod.getMethod();
        RepeatSubmit repeatSubmit = method.getAnnotation(RepeatSubmit.class);
        // 如果没有注解，直接通过
        if (repeatSubmit == null) {
            return true;
        }

        // 获取用户信息
//        String account = request.getHeader(BaseIbuSetting.SF_USER_NAME_KEY);
        String account = UserContextSimple.getCurrentUserName();
//        User user = (User) SecurityContextHolder.getContext().getAuthentication().getPrincipal();
//        String account=user.getAccount();
        // 以url地址为判断加帐号做为判断依据，如果redis里存在相关信息，则表示近期刚提交过
        if (hasFlag(request, request.getServletPath(), account)) {
            log.warn("数据重复提交,url:" + request.getServletPath());
            throw new CommonException("请勿重复提交!");
        }
        redisUtil.setString(request.getServletPath() + "_" + account, "1", repeatSubmit.delay());
        return true;
    }

    private boolean hasFlag(HttpServletRequest request, String path, String token) {
        // 检查redis中是否存在以前提交过的flag
        return redisUtil.hasKey(path + "_" + token);

    }

}

3.拦截器加入配置类

@Configuration
public class WebMvcConfig implements WebMvcConfigurer {

    @Bean
    public RepeatSubmitInterceptor repeatSubmitInterceptor() {
        return new RepeatSubmitInterceptor();
    }

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(repeatSubmitInterceptor());
    }
}