SpringBoot自定义注解+Redis+拦截器实现限流

忘是亡心i 2022-10-23 08:02 218阅读 0赞

1.添加redis 依赖包

>     <dependency>
>         <groupId>org.springframework.boot</groupId>
>         <artifactId>spring-boot-starter-data-redis</artifactId>
>     </dependency>

2.自定义注解 AccessLimit

>     @Inherited
>     @Documented
>     @Target({ElementType.FIELD, ElementType.TYPE, ElementType.METHOD})
>     @Retention(RetentionPolicy.RUNTIME)
>     public @interface AccessLimit {
>         //标识 指定sec时间段内的访问次数限制
>         int limit() default 5;
>     
>         //标识 时间段
>         int seconds() default 5;
>     }

3. 添加拦截器 AccessLimitInterceptor

public class AccessLimitInterceptor implements HandlerInterceptor {
    
        @Autowired
        private RedisTemplate<String, Integer> redisTemplate;
    
        @Override
        public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
            if (handler instanceof HandlerMethod) {
                HandlerMethod handlerMethod = (HandlerMethod) handler;
                Method method = handlerMethod.getMethod();
                if (!method.isAnnotationPresent(AccessLimit.class)) {
                    return true;
                }
                AccessLimit accessLimit = method.getAnnotation(AccessLimit.class);
                if (accessLimit == null) {
                    return true;
                }
                int limit = accessLimit.limit();
                int sec = accessLimit.seconds();
                String key = IPUtil.getIpAddr(request) + request.getRequestURI();
                Integer maxLimit = redisTemplate.opsForValue().get(key);
                if (maxLimit == null) {
                    //set时一定要加过期时间
                    redisTemplate.opsForValue().set(key, 1, sec, TimeUnit.SECONDS);
                } else if (maxLimit < limit) {
                    redisTemplate.opsForValue().set(key, maxLimit + 1, sec, TimeUnit.SECONDS);
                } else {
                    output(response, "请求太频繁!");
                    return false;
                }
            }
            return true;
        }
    
        public void output(HttpServletResponse response, String msg) throws IOException {
            response.setContentType("application/json;charset=UTF-8");
            ServletOutputStream outputStream = null;
            try {
                outputStream = response.getOutputStream();
                outputStream.write(msg.getBytes("UTF-8"));
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                outputStream.flush();
                outputStream.close();
            }
        }
    
    
        @Override
        public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
    
        }
    
        @Override
        public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
    
        }
    }

4.方法上加上注解  @AccessLimit(seconds = 60,limit = 3)

>     @Slf4j
>     @RestController
>     @RequestMapping("/app/user/login")
>     @AllArgsConstructor
>     public class AppUserLoginController {
>     
>         private final IUserService userService;
>     
>         @AccessLimit(seconds = 60,limit = 3)
>         @PostMapping("/getVerificationCode")
>         public RestResponse getVerificationCode(@RequestParam("mobile") String mobile) {
>             try {
>                 if (!StringRegexUtils.verifyMobilePhone(mobile)) {
>                     return RestResponse.fail("手机号不正确");
>                 }
>                 if (userService.getVerificationCode(mobile, 0)) {
>                     return RestResponse.success();
>                 }
>             } catch (Exception e) {
>                 e.printStackTrace();
>                 log.error(e.getMessage());
>                 return RestResponse.fail(e.getMessage());
>             }
>             return RestResponse.fail();
>         }
> 
>  \}

5.注入拦截器

>     @Configuration
>     public class WebInterceptorAdapter implements WebMvcConfigurer {
>     
>         @Bean
>         public HandlerInterceptor getInterceptor() {
>             return new AccessLimitInterceptor();
>         }
>     
>         @Override
>         public void configurePathMatch(PathMatchConfigurer configurer) {
>             AntPathMatcher pathMatcher = new AntPathMatcher();
>             pathMatcher.setCaseSensitive(false);
>             configurer.setPathMatcher(pathMatcher);
>         }
>     
>         @Override
>         public void addInterceptors(InterceptorRegistry registry) {
>             registry.addInterceptor(getInterceptor());
>         }
>     }