Sentinel使用指南

package net.biancheng.c.controller;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
@Slf4j
public class SentinelFlowLimitController {
    @Value("${server.port}")
    private String serverPort;
    @GetMapping("/testA")
    public String testA() {
        return "jiahe提醒您，服务访问成功------testA";
    }
    @GetMapping("/testB")
    public String testB() {
        return "jiahe提醒您，服务访问成功------testB"
    }
}

package net.biancheng.c;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
@SpringBootApplication
@EnableDiscoveryClient
public class SpringCloudAlibabaSentinelService8401Application {
    public static void main(String[] args) {
        SpringApplication.run(SpringCloudAlibabaSentinelService8401Application.class, args);
    }
}

package net.biancheng.c.controller;

import com.alibaba.csp.sentinel.Entry;
import com.alibaba.csp.sentinel.SphO;
import com.alibaba.csp.sentinel.SphU;
import com.alibaba.csp.sentinel.slots.block.BlockException;
import com.alibaba.csp.sentinel.slots.block.RuleConstant;
import com.alibaba.csp.sentinel.slots.block.flow.FlowRule;
import com.alibaba.csp.sentinel.slots.block.flow.FlowRuleManager;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.ArrayList;
import java.util.List;

@RestController
@Slf4j
public class SentinelFlowLimitController {

    @Value("${server.port}")
    private String serverPort;

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

    @GetMapping("/testB")
    public String testB() {
        return "jiahe提醒您，服务访问成功------testB";
    }


    /**
     * 通过 SphU 手动定义资源
     * @return
     */
    public String testAbySphU() {
        Entry entry = null;
        try {
            entry = SphU.entry("testAbySphU");
            //您的业务逻辑 - 开始
            log.info("jiahe提醒您，服务访问成功------testA："+serverPort);
            return "jiahe提醒您，服务访问成功------testA："+serverPort;
            //您的业务逻辑 - 结束
        } catch (BlockException e1) {
            //流控逻辑处理 - 开始
            log.info("jiahe提醒您，testA 服务被限流");
            return "jiahe提醒您，testA 服务被限流";
            //流控逻辑处理 - 结束
        } finally {
            if (entry != null) {
                entry.exit();
            }
        }
    }
}

package net.biancheng.c.controller;

import com.alibaba.csp.sentinel.Entry;
import com.alibaba.csp.sentinel.SphO;
import com.alibaba.csp.sentinel.SphU;
import com.alibaba.csp.sentinel.slots.block.BlockException;
import com.alibaba.csp.sentinel.slots.block.RuleConstant;
import com.alibaba.csp.sentinel.slots.block.flow.FlowRule;
import com.alibaba.csp.sentinel.slots.block.flow.FlowRuleManager;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.ArrayList;
import java.util.List;

@RestController
@Slf4j
public class SentinelFlowLimitController {

    @Value("${server.port}")
    private String serverPort;


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

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

    /**
     * 通过 SphU 手动定义资源
     *
     * @return
     */
    public String testAbySphU() {
        Entry entry = null;
        try {
            entry = SphU.entry("testAbySphU");
            //您的业务逻辑 - 开始
            log.info("jiahe提醒您，服务访问成功------testA：" + serverPort);
            return "jiahe提醒您，服务访问成功------testA：" + serverPort;
            //您的业务逻辑 - 结束
        } catch (BlockException e1) {
            //流控逻辑处理 - 开始
            log.info("jiahe提醒您，testA 服务被限流");
            return "jiahe提醒您，testA 服务被限流";
            //流控逻辑处理 - 结束
        } finally {
            if (entry != null) {
                entry.exit();
            }
        }
    }

    /**
     * 通过 SphO 手动定义资源
     *
     * @return
     */
    public String testBbySphO() {
        if (SphO.entry("testBbySphO")) {
            // 务必保证finally会被执行
            try {
                log.info("jiahe提醒您，服务访问成功------testB：" + serverPort);
                return "jiahe提醒您，服务访问成功------testB：" + serverPort;
            } finally {
                SphO.exit();
            }
        } else {
            // 资源访问阻止，被限流或被降级
            //流控逻辑处理 - 开始
            log.info("jiahe提醒您，testB 服务被限流");
            return "jiahe提醒您，testB 服务被限流";
            //流控逻辑处理 - 结束
        }
    }
}

@GetMapping("/testC")
@SentinelResource(value = "testCbyAnnotation") //通过注解定义资源
public String testC() {
    log.info("jiahe提醒您，服务访问成功------testC：" + serverPort);
    return "jiahe提醒您，服务访问成功------testC：" + serverPort;
}

/**
 * 通过 Sentinel 控制台定义流控规则
 *
 * @return
 */
@GetMapping("/testD")
public String testD() {
    log.info("jiahe提醒您，服务访问成功------testD：" + serverPort);
    return "jiahe提醒您，服务访问成功------testD：" + serverPort;
}

/**
 * 通过 Sentinel 控制台定义流控规则
 *
 */
@GetMapping("/testD")
@SentinelResource(value = "testD-resource", blockHandler = "blockHandlerTestD") //通过注解定义资源
public String testD() {
    log.info("jiahe提醒您，服务访问成功------testD：" + serverPort);
    return "jiahe提醒您，服务访问成功------testD：" + serverPort;
}
/**
 * 限流之后的逻辑
 * @param exception
 * @return
 */
public String blockHandlerTestD(BlockException exception) {
    log.info(Thread.currentThread().getName() + "jiahe提醒您，TestD服务访问失败! 您已被限流，请稍后重试");
    return "jiahe提醒您，TestD服务访问失败! 您已被限流，请稍后重试";
}

public static void loadRules(List<FlowRule> rules) {
    currentProperty.updateValue(rules);
}

/**
 * 通过代码定义流量控制规则
 */
private static void initFlowRules() {
    List<FlowRule> rules = new ArrayList<>();
    //定义一个限流规则对象
    FlowRule rule = new FlowRule();
    //资源名称
    rule.setResource("testD-resource");
     //限流阈值的类型
    rule.setGrade(RuleConstant.FLOW_GRADE_QPS);
    // 设置 QPS 的阈值为 2
    rule.setCount(2);
    rules.add(rule);
    //定义限流规则
    FlowRuleManager.loadRules(rules);
}

@GetMapping("/testD")
@SentinelResource(value = "testD-resource", blockHandler = "blockHandlerTestD") //通过注解定义资源
public String testD() {
    initFlowRules(); //调用初始化流控规则的方法
    log.info("jiahe提醒您，服务访问成功------testD：" + serverPort);
    return "jiahe提醒您，服务访问成功------testD：" + serverPort;
}

package net.biancheng.c.entity;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import lombok.experimental.Accessors;
import java.io.Serializable;
@AllArgsConstructor
@NoArgsConstructor //无参构造函数
@Data // 提供类的get、set、equals、hashCode、canEqual、toString 方法
@Accessors(chain = true)
public class Dept implements Serializable {
    private Integer deptNo;
    private String deptName;
    private String dbSource;
}

package net.biancheng.c.entity;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
@Data
@AllArgsConstructor
@NoArgsConstructor
public class CommonResult<T> {
    private Integer code;
    private String message;
    private T data;
    public CommonResult(Integer code, String message) {
        this(code, message, null);
    }
}

package net.biancheng.c.mapper;
import net.biancheng.c.entity.Dept;
import org.apache.ibatis.annotations.Mapper;
import java.util.List;
@Mapper
public interface DeptMapper {
    //根据主键获取数据
    Dept selectByPrimaryKey(Integer deptNo);
    //获取表中的全部数据
    List<Dept> GetAll();
}

package net.biancheng.c.service;
import net.biancheng.c.entity.Dept;
import java.util.List;
public interface DeptService {
    Dept get(Integer deptNo);
    List<Dept> selectAll();
}

package net.biancheng.c.service.impl;
import net.biancheng.c.entity.Dept;
import net.biancheng.c.mapper.DeptMapper;
import net.biancheng.c.service.DeptService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;
@Service("deptService")
public class DeptServiceImpl implements DeptService {
    @Autowired
    private DeptMapper deptMapper;
    @Override
    public Dept get(Integer deptNo) {
        return deptMapper.selectByPrimaryKey(deptNo);
    }
    @Override
    public List<Dept> selectAll() {
        return deptMapper.GetAll();
    }
}

package net.biancheng.c.controller;

import lombok.extern.slf4j.Slf4j;
import net.biancheng.c.entity.CommonResult;
import net.biancheng.c.entity.Dept;
import net.biancheng.c.service.DeptService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;
import java.util.concurrent.TimeUnit;

@RestController
@Slf4j
public class DeptController {
    @Autowired
    private DeptService deptService;

    @Value("${server.port}")
    private String serverPort;

    @RequestMapping(value = "/dept/get/{id}", method = RequestMethod.GET)
    public CommonResult<Dept> get(@PathVariable("id") int id) {
        log.info("端口：" + serverPort + "\t+ dept/get/");
        try {
            TimeUnit.SECONDS.sleep(1);
            log.info("休眠 1秒");
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        Dept dept = deptService.get(id);
        CommonResult<Dept> result = new CommonResult(200, "from mysql,serverPort:  " + serverPort, dept);
        return result;
    }

    @RequestMapping(value = "/dept/list", method = RequestMethod.GET)
    public CommonResult<List<Dept>> list() {
        log.info("端口：" + serverPort + "\t+ dept/list/");

        List<Dept> depts = deptService.selectAll();
        CommonResult<List<Dept>> result = new CommonResult(200, "from mysql,serverPort:  " + serverPort, depts);
        return result;
    }
}

package net.biancheng.c;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;

@SpringBootApplication
@EnableDiscoveryClient
public class SpringCloudAlibabaProviderMysql8003Application {
    public static void main(String[] args) {
        SpringApplication.run(SpringCloudAlibabaProviderMysql8003Application.class, args);
    }
}

package net.biancheng.c.service;
import net.biancheng.c.entity.CommonResult;
import net.biancheng.c.entity.Dept;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.stereotype.Component;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import java.util.List;

@Component
@FeignClient(value = "spring-cloud-alibaba-provider-mysql", fallback = DeptFallbackService.class)
public interface DeptFeignService {
    @RequestMapping(value = "/dept/get/{id}", method = RequestMethod.GET)
    public CommonResult<Dept> get(@PathVariable("id") int id);
    @RequestMapping(value = "/dept/list", method = RequestMethod.GET)
    public CommonResult<List<Dept>> list();
}

package net.biancheng.c.controller;

import com.alibaba.csp.sentinel.annotation.SentinelResource;
import com.alibaba.csp.sentinel.slots.block.degrade.circuitbreaker.CircuitBreaker;
import com.alibaba.csp.sentinel.slots.block.degrade.circuitbreaker.EventObserverRegistry;
import com.alibaba.csp.sentinel.util.TimeUtil;
import lombok.extern.slf4j.Slf4j;
import net.biancheng.c.entity.CommonResult;
import net.biancheng.c.entity.Dept;
import net.biancheng.c.service.DeptFeignService;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;

@RestController
@Slf4j
public class DeptFeignController {
    @Resource
    DeptFeignService deptFeignService;

    @RequestMapping(value = "consumer/feign/dept/get/{id}", method = RequestMethod.GET)
    @SentinelResource(value = "fallback", fallback = "handlerFallback")
    public CommonResult<Dept> get(@PathVariable("id") int id) {
        monitor();
        System.out.println("--------->>>>主业务逻辑");
        CommonResult<Dept> result = deptFeignService.get(id);
        if (id == 6) {
            System.err.println("--------->>>>主业务逻辑，抛出非法参数异常");
            throw new IllegalArgumentException("IllegalArgumentException，非法参数异常....");
            //如果查到的记录也是 null 也控制正异常
        } else if (result.getData() == null) {
            System.err.println("--------->>>>主业务逻辑，抛出空指针异常");
            throw new NullPointerException("NullPointerException，该ID没有对应记录,空指针异常");
        }
        return result;
    }

    @RequestMapping(value = "consumer/feign/dept/list", method = RequestMethod.GET)
    public CommonResult<List<Dept>> list() {
        return deptFeignService.list();
    }

    //处理异常的回退方法（服务降级）
    public CommonResult handlerFallback(@PathVariable int id, Throwable e) {
        System.err.println("--------->>>>服务降级逻辑");
        Dept dept = new Dept(id, "null", "null");
        return new CommonResult(444, "jiahe提醒您，服务被降级！异常信息为：" + e.getMessage(), dept);
    }

    /**
     * 自定义事件监听器，监听熔断器状态转换
     */
    public void monitor() {
        EventObserverRegistry.getInstance().addStateChangeObserver("logging", (prevState, newState, rule, snapshotValue) -> {
            SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
            if (newState == CircuitBreaker.State.OPEN) {
                // 变换至 OPEN state 时会携带触发时的值
                System.err.println(String.format("%s -> OPEN at %s, 发送请求次数=%.2f",
                                                 prevState.name(), format.format(new Date(TimeUtil.currentTimeMillis())), snapshotValue));
            } else {
                System.err.println(String.format("%s -> %s at %s",
                                                 prevState.name(), newState.name(), format.format(new Date(TimeUtil.currentTimeMillis()))));
            }
        });
    }
}

package net.biancheng.c;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.openfeign.EnableFeignClients;
@SpringBootApplication
@EnableDiscoveryClient
@EnableFeignClients
public class SpringCloudAlibabaConsumerMysql8803Application {
    public static void main(String[] args) {
        SpringApplication.run(SpringCloudAlibabaConsumerMysql8803Application.class, args);
    }
}

public static void loadRules(List<DegradeRule> rules) {
    try {
        currentProperty.updateValue(rules);
    } catch (Throwable var2) {
        RecordLog.error("[DegradeRuleManager] Unexpected error when loading degrade rules", var2);
    }
}

/**
 * 初始化熔断策略
 */
private static void initDegradeRule() {
    List<DegradeRule> rules = new ArrayList<>();
    DegradeRule rule = new DegradeRule("fallback");
    //熔断策略为异常比例
    rule.setGrade(CircuitBreakerStrategy.ERROR_RATIO.getType());
    //异常比例阈值
    rule.setCount(0.7);
    //最小请求数
    rule.setMinRequestAmount(100);
    //统计市场，单位毫秒
    rule.setStatIntervalMs(30000);
    //熔断市场，单位秒
    rule.setTimeWindow(10);
    rules.add(rule);
    DegradeRuleManager.loadRules(rules);
}

@RequestMapping(value = "consumer/feign/dept/get/{id}", method = RequestMethod.GET)
@SentinelResource(value = "fallback", fallback = "handlerFallback")
public CommonResult<Dept> get(@PathVariable("id") int id) {
    initDegradeRule();
    monitor();
    System.out.println("--------->>>>主业务逻辑");
    CommonResult<Dept> result = deptFeignService.get(id);
    if (id == 6) {
        System.err.println("--------->>>>主业务逻辑，抛出非法参数异常");
        throw new IllegalArgumentException("IllegalArgumentException，非法参数异常....");
        //如果查到的记录也是 null 也控制正异常
    } else if (result.getData() == null) {
        System.err.println("--------->>>>主业务逻辑，抛出空指针异常");
        throw new NullPointerException("NullPointerException，该ID没有对应记录,空指针异常");
    }
    return result;
}