sentinel详解——流控、降级、热点、熔断

Sentinel（哨兵）是一个面向微服务的流量控制、熔断降级的组件，支持界面化的细粒度统一配置；可以对微服务进行可视化的监控和保护；同时可和nacos、dubbo、redis等结合使用。

一、后端代码中sentinel配置

1、引入pom

 <!--SpringCloud ailibaba nacos -->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>
        
        <!--SpringCloud ailibaba sentinel-datasource-nacos 后续做持久化用到-->
        <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>
        
        <!--openfeign-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>

2、引入yml

server:
  port: 8401

spring:
  application:<