Sentinel规则持久化

一旦重启应用，Sentinel规则将消失，生产环境需要将配置规则进行持久化。

推模式架构图

 

 

 原理简述：

• 控制台推送规则：
  • 将规则推送到Nacos或其他远程配置中心
  • Sentinel客户端连接Nacos，获取规则配置；并监听Nacos配置变化，如发生变化，就更新本地缓存（从而让本地缓存总是和Nacos一致）
• 控制台监听Nacos配置变化，如发生变化就更新本地缓存（从而让控制台本地缓存总是和Nacos一致）

微服务改造

1，添加依赖

<dependency>
    <groupId>com.alibaba.csp</groupId>
    <artifactId>sentinel-datasource-nacos</artifactId>
</dependency>

2，添加YML配置

spring: cloud: sentinel: datasource: # 名称随意 flow: nacos: server-addr: localhost:8848 dataId: ${spring.application.name}-flow-rules groupId: SENTINEL_GROUP # 规则类型，取值见： # org.springframework.cloud.alibaba.sentinel.datasource.RuleType rule-type: flow degrade: nacos: server-addr: localhost:8848 dataId: ${spring.application.name}-degrade-rules groupId: SENTINEL_GROUP rule-type: degrade system: nacos: server-addr: localhost:8848 dataId: ${spring.application.name}-system-rules groupId: SENTINEL_GROUP rule-type: system authority: nacos: server-addr: localhost:8848 dataId: ${spring.application.name}-authority-rules groupId: SENTINEL_GROUP rule-type: authority param-flow: nacos: server-addr: localhost:8848 dataId: ${spring.application.name}-param-flow-rules groupId: SENTINEL_GROUP rule-type: param-flow

3，在Nacos里面配置sentiel相关的流控规则。

系统演示：

1，POM文件

    <dependencies>
        <!--nacos客户端 服务注册-->
        <dependency> <groupId>com.alibaba.cloud</groupId> <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId> </dependency> <!--sentinel 流量监控，服务熔断，服务降级等--> <dependency> <groupId>com.alibaba.cloud</groupId> <artifactId>spring-cloud-starter-alibaba-sentinel</artifactId> </dependency> <!--持久化--> <dependency> <groupId>com.alibaba.csp</groupId> <artifactId>sentinel-datasource-nacos</artifactId> </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!--web 监控-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
        </dependency>
    </dependencies>

2，YML文件配置

server:
  port: 6001
spring:
  application:
    name: sentienel-dashboard-service
  cloud:
    nacos:
      discovery:
        #nacos服务注册中心地址
        server-addr: localhost:8848
    sentinel:
      transport:
        #sentinel dashboard 地址
        dashboard: localhost:8080
        #默认8179端口
        port: 8179
 datasource: ds: nacos: server-addr: localhost:8848 dataId: sentienel-dashboard-service groupId: DEFAULT_GROUP data-type: json rule-type: flow

#监控暴露
management:
  endpoints:
    web:
      exposure:
        include: "*"

3，主启动类

@SpringBootApplication
@EnableDiscoveryClient public class SentinelDashboard6001Main {
    public static void main(String[] args) {
        SpringApplication.run(SentinelDashboard6001Main.class,args);
    }
}

4，业务类

@RestController
public class SentinelController {
    @GetMapping("/testA")
    public String getA() {
        return "test A";
    }

    @GetMapping("/testB")
    public String getB() {
        return "test B";
    }

    @GetMapping("/testHot")
    @SentinelResource(value = "/hot",blockHandler = "hotHandler")
    public String testHot(@RequestParam(name = "a", required = false) String a, @RequestParam(name = "b", required = false) String b) {
        return a+" "+b;
    }


    public String hotHandler(String a, String b, BlockException exception){
        return "hot key exception";
    }
}

5，在Nacos上配置Sentinel的流控规则

 

•  resource：资源名称
• limitApp：来源应用
• grade：阀值类型，0表示线程数，1表示QPS
• count：单机阈值
• strategy：流控模式，0表示直接，1表示关联，2表示链路
• controllerBehavior：流控效果，0表示快速失败，1表示Warm up，2表示排队等待
• clusterMode：是否集群

6，测试，发现Sentinel能获取流控规则。