SpringBoot + Redis 实现接口限流

女爷i 2023-10-10 12:32 75阅读 0赞

## 前提说明:[SpringBoot 集成封装Redis][SpringBoot _Redis] ##

## 功能说明: ##

使用了Java 注解+Redis实现对接口访问限流控制功能

## 代码说明： ##

### 自定义接口限流注解标签: ###

package com.zzg.common.annotation;
    
    import java.lang.annotation.Documented;
    import java.lang.annotation.ElementType;
    import java.lang.annotation.Inherited;
    import java.lang.annotation.Retention;
    import java.lang.annotation.RetentionPolicy;
    import java.lang.annotation.Target;
    
    /**
     * 自定义限流注解
     * @author zzg
     *
     */
    @Inherited
    @Documented
    @Target({ElementType.FIELD,ElementType.TYPE,ElementType.METHOD})
    @Retention(RetentionPolicy.RUNTIME)
    public @interface AccessLimit {
    	 //指定second 时间内 API请求次数
        int times() default 4;
    
        // 请求次数的指定时间范围  秒数(redis数据过期时间)
        int second() default 10;
    }

### 自定义拦截器解析接口限流注解标签: ###

package com.digipower.component.interceptor;
    
    import java.io.OutputStream;
    
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Component;
    import org.springframework.web.method.HandlerMethod;
    import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;
    
    import com.alibaba.fastjson.JSON;
    import com.digipower.common.annotation.AccessLimit;
    import com.digipower.common.entity.Result;
    import com.digipower.common.util.IpUtils;
    import com.digipower.redis.util.RedisUtil;
    
    /**
     * 接口防刷拦截器
     * @author zzg
     *
     */
    @Component
    public class FangshuaInterceptor extends HandlerInterceptorAdapter {
    	 @Autowired
    	 private RedisUtil redisUtil;
    	 
    	    @Override
    	    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
    	 
    	        //判断请求是否属于方法的请求
    	        if(handler instanceof HandlerMethod){
    	 
    	            HandlerMethod hm = (HandlerMethod) handler;
    	 
    	            //获取方法中的注解,看是否有该注解
    	            AccessLimit accessLimit = hm.getMethodAnnotation(AccessLimit.class);
    	            if(accessLimit == null){
    	                return true;
    	            }
    	            int times = accessLimit.times();//请求次数
                    int second = accessLimit.second();//请求时间范围
    	            
    	            //根据 IP + API 限流
                    String key = IpUtils.getIpAddr(request) + request.getRequestURI();
                    //根据key获取已请求次数
                    Integer maxTimes = (Integer) redisUtil.get(key);
                    
                    if(maxTimes == null){
                        //set时一定要加过期时间
                    	redisUtil.set(key, 1, second);
                    }else if(maxTimes < times){
                    	redisUtil.set(key, maxTimes+1, second);
                    }else{
                    	 //超出访问次数
                        render(response);
                        return false;
                    }
    	        }
    	 
    	        return true;
    	 
    	    }
    	    private void render(HttpServletResponse response)throws Exception {
    	        response.setContentType("application/json;charset=UTF-8");
    	        OutputStream out = response.getOutputStream();
    	        String str  = JSON.toJSONString(Result.error("接口请求过于频繁"));
    	        out.write(str.getBytes("UTF-8"));
    	        out.flush();
    	        out.close();
    	    }
    }

涉及IP工具类:IpUtils源代码:

package com.zzg.common.util;
    
    import javax.servlet.http.HttpServletRequest;
    
    /**
     * IP 工具类
     * @author zzg
     *
     */
    public class IpUtils {
    	 /**
         * IpUtils工具类方法
         * 获取真实的ip地址
         * @param request
         * @return
         */
        public static String getIpAddr(HttpServletRequest request) {
            String ip = request.getHeader("X-Forwarded-For");
            if(org.apache.commons.lang.StringUtils.isNotEmpty(ip) && !"unKnown".equalsIgnoreCase(ip)){
                //多次反向代理后会有多个ip值，第一个ip才是真实ip
                int index = ip.indexOf(",");
                if(index != -1){
                    return ip.substring(0,index);
                }else{
                    return ip;
                }
            }
            ip = request.getHeader("X-Real-IP");
            if(org.apache.commons.lang.StringUtils.isNotEmpty(ip) && !"unKnown".equalsIgnoreCase(ip)){
                return ip;
            }
            return request.getRemoteAddr();
        }
    
    
    }

### 配置拦截器 ###

package com.zzg.config;
    
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.web.servlet.config.annotation.EnableWebMvc;
    import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
    import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
    import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
    
    import com.zzg.component.interceptor.FangshuaInterceptor;
    
    @Configuration
    @EnableWebMvc
    public class SpringMVCConfig extends WebMvcConfigurerAdapter {
    	/**
    	 * 资源处理
    	 */
    	@Override
    	public void addResourceHandlers(ResourceHandlerRegistry registry) {
    		registry.addResourceHandler("swagger-ui.html").addResourceLocations("classpath:/META-INF/resources/");
    		registry.addResourceHandler("/webjars/**").addResourceLocations("classpath:/META-INF/resources/webjars/");
    		// 资源图片映射(静态配置->基于数据库实现动态配置)
    	    registry.addResourceHandler("/upload_file/**").addResourceLocations("file:F:/data/upload_file/");
    		super.addResourceHandlers(registry);
    	}
    	
    	// 限流拦截器
    	@Bean
        public FangshuaInterceptor accessLimitInterceptor(){
            return new FangshuaInterceptor();
        }
    
    	@Override
    	public void addInterceptors(InterceptorRegistry registry) {
    		// TODO Auto-generated method stub
    		//API限流拦截
            registry.addInterceptor(accessLimitInterceptor()).addPathPatterns("/**").excludePathPatterns("/swagger-ui.html/**", "/swagger-resources/**", "/webjars/**", "/v2/api-docs/**");
    	}
    	
    	
    	
    	
    }

### 在项目的验证码接口使用接口限流注解： ###

/**
    	 * 1、生成验证码
    	 * @param httpServletRequest
    	 * @param httpServletResponse
    	 * @throws Exception
    	 */
    	@AccessLimit(times = 5, second=10)
    	@RequestMapping("/defaultKaptcha")
    	public void defaultKaptcha(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse)
    			throws Exception {
    		byte[] captchaChallengeAsJpeg = null;
    		ByteArrayOutputStream jpegOutputStream = new ByteArrayOutputStream();
    		try {
    			// 生产验证码字符串并保存到数据库中
    			String createText = defaultKaptcha.createText();
    			saveVerificationCode(createText);
    			httpServletRequest.getSession().setAttribute("rightCode", createText);
    			// 使用生产的验证码字符串返回一个BufferedImage对象并转为byte写入到byte数组中
    			BufferedImage challenge = defaultKaptcha.createImage(createText);
    			ImageIO.write(challenge, "jpg", jpegOutputStream);
    		} catch (IllegalArgumentException e) {
    			httpServletResponse.sendError(HttpServletResponse.SC_NOT_FOUND);
    			return;
    		}
    
    		// 定义response输出类型为image/jpeg类型，使用response输出流输出图片的byte数组
    		captchaChallengeAsJpeg = jpegOutputStream.toByteArray();
    		httpServletResponse.setHeader("Cache-Control", "no-store");
    		httpServletResponse.setHeader("Pragma", "no-cache");
    		httpServletResponse.setDateHeader("Expires", 0);
    		httpServletResponse.setContentType("image/jpeg");
    		ServletOutputStream responseOutputStream = httpServletResponse.getOutputStream();
    		responseOutputStream.write(captchaChallengeAsJpeg);
    		responseOutputStream.flush();
    		responseOutputStream.close();
    	}

### 结果展示: ###

正常访问验证码接口，验证码图片现在正常输出.

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3pob3V6aGl3ZW5nYW5n_size_16_color_FFFFFF_t_70][]

使用F5 频繁刷新验证码接口，会得到如下提示信息:

![20210207121647102.png][]

[SpringBoot _Redis]: https://blog.csdn.net/zhouzhiwengang/article/details/89151017
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3pob3V6aGl3ZW5nYW5n_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20210207121503446.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3pob3V6aGl3ZW5nYW5n,size_16,color_FFFFFF,t_70
[20210207121647102.png]: https://img-blog.csdnimg.cn/20210207121647102.png