SpringCloud Alibaba Sentinel實現熔斷與限流

 

 官網：https://github.com/alibaba/Sentinel

  中文：https://github.com/alibaba/Sentinel/wiki/%E4%BB%8B%E7%BB%8D

 

 

下載：https://github.com/alibaba/Sentinel/releases

 

 

                                 

 

 

 

 

 

運行：

 

 

 

 

 

1  初始化演示工程

 1.1 大綱；

 

 

 1.2  創建cloudalibaba-sentinel-service8401

pom:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <artifactId>cloud2020</artifactId>
        <groupId>com.eiletxie.springcloud</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>cloudalibaba-sentinel-service8401</artifactId>

    <dependencies>
        <!-- SpringCloud ailibaba nacos-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>
        <!-- SpringCloud ailibaba sentinel-datasource-nacos 持久化需要用到-->
        <dependency>
            <groupId>com.alibaba.csp</groupId>
            <artifactId>sentinel-datasource-nacos</artifactId>
        </dependency>
        <!-- SpringCloud ailibaba sentinel-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-sentinel</artifactId>
        </dependency>
        <dependency><!-- 引用自己定義的api通用包，可以使用Payment支付Entity -->
            <groupId>com.eiletxie.springcloud</groupId>
            <artifactId>cloud-api-commons</artifactId>
            <version>${project.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!--監控-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <!--熱部署-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>
</project>

 

yml:

server:
  port: 8401

spring:
  application:
    name: cloudalibaba-sentinal-service
  cloud:
    nacos:
      discovery:
        #Nacos服務注冊中心地址
        server-addr: localhost:8848
    sentinel:
      transport:
        #配置Sentin dashboard地址
        dashboard: localhost:8080
        # 默認8719端口，假如被占用了會自動從8719端口+1進行掃描，直到找到未被占用的 端口
        port: 8719
management:
  endpoints:
    web:
      exposure:
        include: '*'

localhost:8080 控制台的地址，指定控制台后客戶端會自動向該地址發送心跳包 

(默認8719) 客戶端提供給Dashboard訪問或者查看Sentinel的運行訪問的參數

 

主啟動類：

/**
 * @Author EiletXie
 * @Since 2020/3/17 12:52
 */
@EnableDiscoveryClient
@SpringBootApplication
public class MainApp8401 {

    public static void main(String[] args) {
        SpringApplication.run(MainApp8401.class,args);
    }
}

controller:

package com.eiletxie.springcloud.alibaba.controller;

import com.alibaba.csp.sentinel.annotation.SentinelResource;
import com.alibaba.csp.sentinel.slots.block.BlockException;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.util.concurrent.TimeUnit;

/**
 * @Author EiletXie
 * @Since 2020/3/17 12:54
 */
@RestController
@Slf4j
public class FlowLimitController {

    @GetMapping("/testA")
    public String testA() {
        return "----testA";
    }

    @GetMapping("/testB")
    public String testB() {
        return "----testB";
    }
}

 

 空空如也：

 

 執行：

 

 結果：

 

 

流控規則:

 

 

 

 

 

   基本介紹 

 

 

     超過 1次/s:將會報       

 

 

 1 直接：api達到限流條件時，直接限流

 

 

 

 

 

 

 閥值類型的QPS和線程數的區別：

         QPS (每秒鍾的請求數量) :當調用該api的QPS達到閾值的時候，進行限流

        線程數:當調用該api的線程數達到閾值的時候，進行限流

 

 

去掉暫停毫秒的代碼，就是普通的QPS的模擬

 

 

 

 2 關聯: 當關聯的資源達到閾值時，就限流自己

 

 

 

 

 

模擬訪問B

 

 

結論：大批量線程高並發訪問B，導致A失效了

 

 

 

 

流控效果:

 

 

 

 

 

 

2 預熱:

 

 

 

 

 

應用場景：

 

 

 

 3：排隊等待

 

 

 

 

降級規則：

 

 

 

 

 

 

 

 

 

1 RT

 

 

 

 

 

 

效果演示：

 

 

 

 

 

 

 

 

 2：異常比例

 

 

 

 

 

 

 效果演示：

 

 

 

 

 

 

 

 

 

 

 

 

3：異常數：

 

 

 

 

 效果演示：

 

 

 

     -  -------》   

 

 

 

 

熱點key限流：

官網：https://github.com/alibaba/Sentinel/wiki/熱點參數限流

 

 

 

 效果演示：

 

 

 

 

 

 

 

 

 錯誤頁面：（無blockHandler的兜底方法）

 

 

 

 參數例外項

 

 

 

 

 手動異常：

 

結論：

 

 

 

 系統規則：(系統入口的限流，而非細粒度的rest)

官網：https://github.com/alibaba/Sentinel/wiki/%E7%B3%BB%E7%BB%9F%E8%87%AA%E9%80%82%E5%BA%94%E9%99%90%E6%B5%81

 

 

 

 

 

 

 

 

 

 

 

 

@SentinelResource

 

  增加的流控規則隨着關閉8401,流控規則消失----------》解決需要規則持久化

 

 

 

 

 無兜底方法;

 

 

 

 

 

客戶自定義限流處理邏輯:

 

 

 

 

服務熔斷功能（重要）

 1：ribbon系列：

 

 

 9003和9004的

ymL:

 

 

 

 

 

 

 

 

 84:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

案例2;

 

 

 

效果：

     - ---------》   

 

 案例3：

 

 

 

 

 

 兩者都配的結論：在QPS的合理配置內，走fallback，一旦超出合理配置則走bloackHandler

 

 

 

 2：feign系類：

大綱：

 

 

 pom

 

 

 

 

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <artifactId>cloud2020</artifactId>
        <groupId>com.eiletxie.springcloud</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>cloudalibaba-sentinel-service8401</artifactId>

    <dependencies>
        <!-- SpringCloud ailibaba nacos-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>
        <!-- SpringCloud ailibaba sentinel-datasource-nacos 持久化需要用到-->
        <dependency>
            <groupId>com.alibaba.csp</groupId>
            <artifactId>sentinel-datasource-nacos</artifactId>
        </dependency>
        <!-- SpringCloud ailibaba sentinel-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-sentinel</artifactId>
        </dependency>
        <dependency><!-- 引用自己定義的api通用包，可以使用Payment支付Entity -->
            <groupId>com.eiletxie.springcloud</groupId>
            <artifactId>cloud-api-commons</artifactId>
            <version>${project.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!--監控-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <!--熱部署-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>
</project>

yml：

 

 

server:
  port: 8401

spring:
  application:
    name: cloudalibaba-sentinal-service
  cloud:
    nacos:
      discovery:
        #Nacos服務注冊中心地址
        server-addr: localhost:8848
    sentinel:
      transport:
        #配置Sentin dashboard地址
        dashboard: localhost:8080
        # 默認8719端口，假如被占用了會自動從8719端口+1進行掃描，直到找到未被占用的 端口
        port: 8719
      datasource:
        ds1:
          nacos:
            server-addr: localhost:8848
            dataId: cloudalibaba-sentinel-service
            groupId: DEFAULT_GROUP
            data-type: json
            rule-type: flow

management:
  endpoints:
    web:
      exposure:
        include: '*'

feign:
  sentinel:
    enabled: true #激活Sentinel 對Feign的支持

主啟動類：

 

 業務代碼：

 

 

 

 

 

 

 

 測試84調用9003，此時故意關閉9003微服務提供者，看84消費側自動降級，不會被耗死

 

 熔斷框架的區別

 

 

規則持久化；

  大綱：

 

 修改cloudalibaba-sentinel-service8401

POM:

 

 

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <artifactId>cloud2020</artifactId>
        <groupId>com.eiletxie.springcloud</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>cloudalibaba-sentinel-service8401</artifactId>

    <dependencies>
        <!-- SpringCloud ailibaba nacos-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>
        <!-- SpringCloud ailibaba sentinel-datasource-nacos 持久化需要用到-->
        <dependency>
            <groupId>com.alibaba.csp</groupId>
            <artifactId>sentinel-datasource-nacos</artifactId>
        </dependency>
        <!-- SpringCloud ailibaba sentinel-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-sentinel</artifactId>
        </dependency>
        <dependency><!-- 引用自己定義的api通用包，可以使用Payment支付Entity -->
            <groupId>com.eiletxie.springcloud</groupId>
            <artifactId>cloud-api-commons</artifactId>
            <version>${project.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!--監控-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <!--熱部署-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>
</project>

 

 

server:
  port: 8401

spring:
  application:
    name: cloudalibaba-sentinal-service
  cloud:
    nacos:
      discovery:
        #Nacos服務注冊中心地址
        server-addr: localhost:8848
    sentinel:
      transport:
        #配置Sentin dashboard地址
        dashboard: localhost:8080
        # 默認8719端口，假如被占用了會自動從8719端口+1進行掃描，直到找到未被占用的 端口
        port: 8719
      datasource:
        ds1:
          nacos:
            server-addr: localhost:8848
            dataId: cloudalibaba-sentinel-service
            groupId: DEFAULT_GROUP
            data-type: json
            rule-type: flow

management:
  endpoints:
    web:
      exposure:
        include: '*'

feign:
  sentinel:
    enabled: true #激活Sentinel 對Feign的支持

 

 

 

 

 

 

 

 

 

 快速訪問測試接口:

 停止8401再看sentinel:

 

 重啟8401：