1. Sentinel 是什么?
Sentinel是由阿里中间件团队开源的,面向分布式服务架构的轻量级高可用流量控制组件。
2. 主要优势和特性
轻量级,核心库无多余依赖,性能损耗小。
方便接入,开源生态广泛。
丰富的流量控制场景。
易用的控制台,提供实时监控、机器发现、规则管理等能力。
完善的扩展性设计,提供多样化的 SPI 接口,方便用户根据需求给 Sentinel 添加自定义的逻辑。
3、Sentinel、Hystrix、Resilience4j的异同
4、怎么安装和启动Dashboard
github地址
https://github.com/alibaba/Sentinel/releases
wget -P /opt/downloads https://github.com/alibaba/Sentinel/releases/download/1.6.0/sentinel-dashboard-1.7.1.jar
mkdir /opt/sentinel-dashboard
cp /opt/downloads/sentinel-dashboard-1.7.1.jar /opt/sentinel-dashboard/sentinel-dashboard-1.7.1.jar
启动:java -Dserver.port=8718 -jar sentinel-dashboard-1.7.1.jar
账号密码 sentinel sentinel
5、集成代码:
<?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">
<modelVersion>4.0.0</modelVersion>
<groupId>org.bc.sentinel</groupId>
<artifactId>sentinel-study</artifactId>
<version>1.0-SNAPSHOT</version>
<modules>
<module>sentinel-provider</module>
<module>sentinel-consumer-01</module>
</modules>
<packaging>pom</packaging>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.3.1.RELEASE</version>
</parent>
<properties>
<!-- Spring Cloud Hoxton.SR8 依赖 -->
<spring-cloud.version>Hoxton.SR8</spring-cloud.version>
<!-- spring cloud alibaba 依赖 -->
<spring-cloud-alibaba.version>2.2.4.RELEASE</spring-cloud-alibaba.version>
</properties>
<dependencies>
<!-- lombok 工具通过在代码编译时期动态的将注解替换为具体的代码,
IDEA 需要添加 lombok 插件 -->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.16.18</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
<version>3.11</version>
</dependency>
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-collections4</artifactId>
<version>4.4</version>
</dependency>
<dependency>
<groupId>cn.hutool</groupId>
<artifactId>hutool-all</artifactId>
<version>5.6.0</version>
</dependency>
<!-- 引入jwt-->
<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt-api</artifactId>
<version>0.10.5</version>
</dependency>
<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt-impl</artifactId>
<version>0.10.5</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>io.jsonwebtoken</groupId>
<artifactId>jjwt-jackson</artifactId>
<version>0.10.5</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.47</version>
</dependency>
</dependencies>
<!-- 项目依赖管理 父项目只是声明依赖,子项目需要写明需要的依赖(可以省略版本信息) -->
<dependencyManagement>
<dependencies>
<!-- spring cloud 依赖 -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
<!-- spring cloud alibaba 依赖 -->
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-alibaba-dependencies</artifactId>
<version>${spring-cloud-alibaba.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<!-- 配置远程仓库 -->
<repositories>
<repository>
<id>spring-milestones</id>
<name>Spring Milestones</name>
<url>https://repo.spring.io/milestone</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</repository>
</repositories>
</project>
<?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>sentinel-study</artifactId>
<groupId>org.bc.sentinel</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<packaging>jar</packaging>
<artifactId>sentinel-provider</artifactId>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!--热部署-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<!-- 服务注册 服务发现需要引入的 -->
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
</dependency>
<!--健康监控-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<!--Nacos 配置中心依赖-->
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
</dependency>
<!--Sentinel 组件依赖-->
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-sentinel</artifactId>
</dependency>
<!--sentinel持久化 访问nacos数据源的依赖-->
<dependency>
<groupId>com.alibaba.csp</groupId>
<artifactId>sentinel-datasource-nacos</artifactId>
</dependency>
<!--集群流控客户端依赖-->
<dependency>
<groupId>com.alibaba.csp</groupId>
<artifactId>sentinel-cluster-client-default</artifactId>
</dependency>
<!--集群流控服务端依赖-->
<dependency>
<groupId>com.alibaba.csp</groupId>
<artifactId>sentinel-cluster-server-default</artifactId>
</dependency>
</dependencies>
</project>
<?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>sentinel-study</artifactId>
<groupId>org.bc.sentinel</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<packaging>jar</packaging>
<artifactId>sentinel-consumer-01</artifactId>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!--热部署-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<!-- 服务注册 服务发现需要引入的 -->
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
</dependency>
<!--健康监控-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<!--Nacos 配置中心依赖-->
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
</dependency>
<!--Sentinel 组件依赖-->
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-sentinel</artifactId>
</dependency>
<!--sentinel持久化 访问nacos数据源的依赖-->
<dependency>
<groupId>com.alibaba.csp</groupId>
<artifactId>sentinel-datasource-nacos</artifactId>
</dependency>
</dependencies>
<build>
<plugins>
<!-- spring boot打包-->
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<executions>
<execution>
<configuration>
<mainClass>com.springcloudalibaba.sentinel.SentinelConsumerApplication</mainClass> <!--也可以不指定MainClass,一般能自动识别-->
</configuration>
<goals>
<goal>repackage</goal> <!--依赖包装入jar包-->
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
server:
port: 8082 #程序端口号
spring:
application:
name: sentinel-provider #应用名称
cloud:
sentinel:
transport:
port: 8719 #启动HTTP Server,并且该服务将与Sentinel仪表板进行交互,使Sentinel仪表板可以控制应用 如果被占用则从8719依次+1扫描
dashboard: 127.0.0.1:8718 # 指定仪表盘地址
nacos:
discovery:
server-addr: 127.0.0.1:8848 #nacos服务注册、发现地址
config:
server-addr: 127.0.0.1:8848 #nacos配置中心地址
file-extension: yml #指定配置内容的数据格式
management:
endpoints:
web:
exposure:
include: '*' #公开所有端点
server:
port: 8081 #程序端口号
spring:
application:
name: sentinel-consumer-01 #应用名称
cloud:
sentinel:
datasource:
ds1: # ds1是自己取得名字
nacos: #表示使用nacos
server-addr: 127.0.0.1:8848 # nacos 服务地址
dataId: sentinel-consumer-ds1 #nacos dataId
groupId: DEFAULT_GROUP # 分组 默认分组
data-type: json # 数据类型 json
rule-type: flow #flow 表示流控规则
ds2: # ds2是自己取得名字
nacos: #表示使用nacos
server-addr: 127.0.0.1:8848 # nacos 服务地址
dataId: sentinel-consumer-ds2 #nacos dataId
groupId: DEFAULT_GROUP # 分组 默认分组
data-type: json # 数据类型 json
rule-type: degrade #degrade 表示流控规则
ds3: # ds3是自己取得名字
nacos: #表示使用nacos
server-addr: 127.0.0.1:8848 # nacos 服务地址
dataId: sentinel-consumer-ds3 #nacos dataId
groupId: DEFAULT_GROUP # 分组 默认分组
data-type: json # 数据类型 json
rule-type: system #system 表示系统规则
transport:
port: 8719 #启动HTTP Server,并且该服务将与Sentinel仪表板进行交互,使Sentinel仪表板可以控制应用 如果被占用则从8719依次+1扫描
dashboard: 127.0.0.1:8718 # 指定仪表盘地址
nacos:
discovery:
server-addr: 127.0.0.1:8848 #nacos服务注册、发现地址
config:
server-addr: 127.0.0.1:8848 #nacos配置中心地址
file-extension: yml #指定配置内容的数据格式
management:
endpoints:
web:
exposure:
include: '*' #公开所有端点
package org.bc.sentinel.controller;
import org.apache.commons.lang3.RandomUtils;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController // @RestController注解是@Controller+@ResponseBody
public class TestController {
@RequestMapping("/test") // 标记是该方法是接口请求
public String test() {
return "sentinel-provider-test() " + RandomUtils.nextInt(0,1000);
}
}
package org.bc.sentinel.controller;
import com.alibaba.csp.sentinel.annotation.SentinelResource;
import com.alibaba.csp.sentinel.slots.block.BlockException;
import org.apache.commons.lang3.RandomUtils;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;
import javax.annotation.Resource;
@RestController // @RestController注解是@Controller+@ResponseBody
public class TestController {
private final String SERVER_URL = "http://sentinel-provider"; // 这里的服务地址填写注册到Nacos的应用名称
@Resource
private RestTemplate restTemplate;
@RequestMapping("/test") // 标记是该方法是接口请求
public String test() {
return restTemplate.getForObject(SERVER_URL + "/test", String.class);//调用提供者/test接口
}
@RequestMapping("/sentinelTest")
public String sentinelTest() { // sentinel组件测试方法
// int i = 1 / 0; // 除数不能为0 ,此处必报错
return "TestController#sentinelTest " + RandomUtils.nextInt(0, 10000);
}
@RequestMapping("/sentinelTestB")
public String sentinelTestB() { // sentinel组件测试方法
return "TestController#sentinelTestB " + RandomUtils.nextInt(0, 10000);
}
@RequestMapping("/sentinelTestC")
public String sentinelTestC() { // sentinel组件测试方法
return "TestController#sentinelTestC " + RandomUtils.nextInt(0, 10000);
}
/* @RequestMapping("/sentinelTest")
public String sentinelTest() { // sentinel组件测试方法
return "TestController#sentinelTest " + RandomUtils.nextInt(0, 10000);
}*/
/* @RequestMapping("/sentinelTest")
public String sentinelTest() { // sentinel组件测试方法
try {
Thread.sleep(1000); // 睡眠1 秒
} catch (InterruptedException e) {
e.printStackTrace();
}
return "TestController#sentinelTest " + RandomUtils.nextInt(0, 10000);
}*/
}
package org.bc.sentinel.conf;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.client.RestTemplate;
@Configuration // 标记是配置类
public class GenericConfiguration { // 常规配置类
@LoadBalanced // 标注此注解后,RestTemplate就具有了客户端负载均衡能力
@Bean
public RestTemplate restTemplate(){ // 创建RestTemplate,并交个Spring容器管理
return new RestTemplate();
}
}