4.Zuul-限流

令牌桶 限流流程图：

RateLimitFilter ：

package com.wangfajun.filter;

import com.alibaba.fastjson.JSON;
import com.google.common.util.concurrent.RateLimiter;
import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;
import com.netflix.zuul.exception.ZuulException;
import com.wangfajun.utils.Result;
import org.springframework.stereotype.Component;
import static org.springframework.cloud.netflix.zuul.filters.support.FilterConstants.PRE_TYPE;
import static org.springframework.cloud.netflix.zuul.filters.support.FilterConstants.SERVLET_DETECTION_FILTER_ORDER;

/**
 * 限流
 */
@Component
public class RateLimitFilter extends ZuulFilter {

    //1个令牌
    private static final RateLimiter rateLimit = RateLimiter.create(1);

    @Override
    public String filterType() {
        return PRE_TYPE;
    }

    @Override
    public int filterOrder() {
        return SERVLET_DETECTION_FILTER_ORDER-1;
    }

    @Override
    public boolean shouldFilter() {
        return true;
    }

    @Override
    public Object run() throws ZuulException {
        RequestContext requestContext = RequestContext.getCurrentContext();
        if(!rateLimit.tryAcquire()){
            requestContext.setSendZuulResponse(false);//不通过
            requestContext.getResponse().setContentType("text/html;charset=UTF-8");
            requestContext.setResponseBody(JSON.toJSONString(Result.REQUEST_LIMIT));
        }
        return null;
    }
}

Result:

package com.wangfajun.utils;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import lombok.ToString;

/**
 * 返回信息封装类
 */
@Data
@ToString
@NoArgsConstructor
@AllArgsConstructor
public class Result {
    private int code;
    private String msg;

    public static Result REQUEST_LIMIT = new Result(-10001, "请求超限");
    public static Result SERVER_ERROR = new Result(-10002, "服务端异常");
    public static Result PARAM_ERROR = new Result(-10003, "token缺失");

}

ReturnInfo:

package com.wangfajun.utils;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import lombok.ToString;

/**
 * 返回信息
 */
@Data
@ToString
@NoArgsConstructor
@AllArgsConstructor
public class ReturnInfo<T> {

    private int returnCode;
    private String returnMsg;
    private T content;

    public ReturnInfo(T content){
        this.content = content;
    }

    public ReturnInfo(Result codeMsg){
        if(codeMsg!=null){
            this.returnCode = codeMsg.getCode();
            this.returnMsg = codeMsg.getMsg();
        }
    }

    //成功
    public static <T> ReturnInfo<T> success(T content){
        return new ReturnInfo<T>(content);
    }

    //成功
    public static <T> ReturnInfo<T> success(Result codeMsg){
        return new ReturnInfo<T>(codeMsg);
    }

    //失败
    public static <T> ReturnInfo<T> error(Result codeMsg){
        return new ReturnInfo<T>(codeMsg);
    }


}

pom:

<dependencies>　
 　　　　<!--eureka-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
　　　　 <!--zuul-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-zuul</artifactId>
        </dependency>
        <!--lombok-->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <!--fastjson-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.38</version>
        </dependency>
</dependencies>

一秒内不停提交请求：响应信息：{"code":-10001,"msg":"请求超限"}