sentinel熔断简单实现

sentinel详细介绍网址

基于qps限流

package main

import (
	"fmt"
	sentinel "github.com/alibaba/sentinel-golang/api"
	"github.com/alibaba/sentinel-golang/core/base"
	"github.com/alibaba/sentinel-golang/core/flow"
	"log"
)

//基于qps配置

func main() {
	//初始化sentinel
	err := sentinel.InitDefault()
	if err != nil {
		log.Fatalf("初始化sentinel 异常：%v", err)
	}

	//配置限流的规则
	_, err = flow.LoadRules([]*flow.Rule{
		{
			Resource:               "some-test", //资源名称
			TokenCalculateStrategy: flow.Direct, //前流量控制器的Token计算策略 目前限流
			ControlBehavior:        flow.Reject, //直接拒绝
			Threshold:              10,          //表示流控阈值
			StatIntervalInMs:       1000,        //1s能传10个
		},

		{
			Resource:               "some-test1", //资源名称
			TokenCalculateStrategy: flow.Direct,  //前流量控制器的Token计算策略 目前限流
			ControlBehavior:        flow.Reject,  //直接拒绝
			Threshold:              10,           //表示流控阈值
			StatIntervalInMs:       1000,         //1s能传10个
		},
	})

	if err != nil {
		log.Fatalf("配置限流的规则 异常：%v", err)
	}

	//目前1s有10个进来
	for i := 0; i < 12; i++ {
		//会调用12次
		e, b := sentinel.Entry("some-test", sentinel.WithTrafficType(base.Inbound)) //(base.Inbound 入口流量配置

		//是否满足规则
		if b != nil {
			fmt.Println("限流了")
		} else {
			fmt.Println("检查通过")
			e.Exit() //退出
		}
	}

}

sentinel的预热和冷启动–>在60s内逐步达到1000

package main

import (
	"fmt"
	sentinel "github.com/alibaba/sentinel-golang/api"
	"github.com/alibaba/sentinel-golang/core/base"
	"github.com/alibaba/sentinel-golang/core/flow"
	"log"
	"math/rand"
	"time"
)

//基于qps配置

func main() {
	//初始化sentinel
	err := sentinel.InitDefault()
	if err != nil {
		log.Fatalf("初始化sentinel 异常：%v", err)
	}

	//配置限流的规则
	_, err = flow.LoadRules([]*flow.Rule{
		{
			Resource:               "some-test", //资源名称
			TokenCalculateStrategy: flow.WarmUp, //预热/冷启动策略
			ControlBehavior:        flow.Reject, //直接拒绝
			Threshold:              1000,        //表示流控阈值
			//StatIntervalInMs:       1000,        //1s能传10个
			WarmUpPeriodSec: 60, //预热时长 1分钟左右达到
		},

		{
			Resource:               "some-test1", //资源名称
			TokenCalculateStrategy: flow.Direct,  //前流量控制器的Token计算策略 目前限流
			ControlBehavior:        flow.Reject,  //直接拒绝
			Threshold:              10,           //表示流控阈值
			StatIntervalInMs:       1000,         //1s能传10个
		},
	})

	if err != nil {
		log.Fatalf("配置限流的规则 异常：%v", err)
	}

	ch := make(chan struct{})
	var globalTotal int
	var passTotal int
	var blockTotal int

	//我会在每一秒统计一次，这一秒之内 你通过了多少，总共有多少， block了多少, 每一秒会产生很多的block
	for i := 0; i < 100; i++ {
		go func() {
			for {
				globalTotal++
				//会调用12次
				e, b := sentinel.Entry("some-test", sentinel.WithTrafficType(base.Inbound)) //(base.Inbound 入口流量配置
				//是否满足规则
				if b != nil {
					//fmt.Println("限流了")
					blockTotal++
					time.Sleep(time.Duration(rand.Uint64()%10) * time.Millisecond)
				} else {
					//fmt.Println("检查通过")
					passTotal++
					time.Sleep(time.Duration(rand.Uint64()%10) * time.Millisecond)
					e.Exit() //退出
				}
			}
		}()
	}
	go func() {
		var oldTotal int //过去1s总共有多少个
		var oldPass int  //过去1s总共pass多少个
		var oldBlock int //过去1s总共block多少个
		for {
			oneSecondTotal := globalTotal - oldTotal
			oldTotal = globalTotal

			oneSecondPass := passTotal - oldPass
			oldPass = passTotal

			oneSecondBlock := blockTotal - oldBlock
			oldBlock = blockTotal

			time.Sleep(time.Second)
			fmt.Printf("total:%d, pass:%d, block:%d\n", oneSecondTotal, oneSecondPass, oneSecondBlock)
		}
	}()

	<-ch

}

匀速通过，更换掉就行，比如一秒你有100个通过，那么就是每10ms通过一个，那么就需要延迟10ms就会全部通过
sentinel的熔断接口
基于错误数

// Copyright 1999-2020 Alibaba Group Holding Ltd.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package main

import (
	"errors"
	"fmt"
	"log"
	"math/rand"
	"time"

	sentinel "github.com/alibaba/sentinel-golang/api"
	"github.com/alibaba/sentinel-golang/core/circuitbreaker"
	"github.com/alibaba/sentinel-golang/core/config"
	"github.com/alibaba/sentinel-golang/logging"
	"github.com/alibaba/sentinel-golang/util"
)

type stateChangeTestListener struct {
}

func (s *stateChangeTestListener) OnTransformToClosed(prev circuitbreaker.State, rule circuitbreaker.Rule) {
	fmt.Printf("rule.steategy: %+v, From %s to Closed, time: %d\n", rule.Strategy, prev.String(), util.CurrentTimeMillis())
}

func (s *stateChangeTestListener) OnTransformToOpen(prev circuitbreaker.State, rule circuitbreaker.Rule, snapshot interface{}) {
	fmt.Printf("rule.steategy: %+v, From %s to Open, snapshot: %d, time: %d\n", rule.Strategy, prev.String(), snapshot, util.CurrentTimeMillis())
}

func (s *stateChangeTestListener) OnTransformToHalfOpen(prev circuitbreaker.State, rule circuitbreaker.Rule) {
	fmt.Printf("rule.steategy: %+v, From %s to Half-Open, time: %d\n", rule.Strategy, prev.String(), util.CurrentTimeMillis())
}

func main() {
	total := 0
	totalPass := 0
	totalBlock := 0
	totalErr := 0
	//创建配置对象
	conf := config.NewDefaultConfig()
	// for testing, logging output to console
	conf.Sentinel.Log.Logger = logging.NewConsoleLogger() //加入loging
	err := sentinel.InitWithConfig(conf)
	if err != nil {
		log.Fatal(err)
	}
	ch := make(chan struct{})
	// Register a state change listener so that we could observer the state change of the internal circuit breaker.
	circuitbreaker.RegisterStateChangeListeners(&stateChangeTestListener{}) //注册，当内部状态转换加一个自己的逻辑

	_, err = circuitbreaker.LoadRules([]*circuitbreaker.Rule{
		// Statistic time span=5s, recoveryTimeout=3s, maxErrorCount=50
		{
			Resource:                     "abc",
			Strategy:                     circuitbreaker.ErrorCount,
			RetryTimeoutMs:               3000, //3s之后进入half-open
			MinRequestAmount:             10,   //静默数
			StatIntervalMs:               5000, //5s统计一次
			StatSlidingWindowBucketCount: 10,   //活动窗口的个数
			Threshold:                    50,   //数量不超过50个
		},
	})
	fmt.Println(circuitbreaker.ErrorCount)
	if err != nil {
		log.Fatal(err)
	}

	logging.Info("[CircuitBreaker ErrorCount] Sentinel Go circuit breaking demo is running. You may see the pass/block metric in the metric log.")
	go func() {
		for {
			total++
			e, b := sentinel.Entry("abc")
			if b != nil {
				totalBlock++
				fmt.Println("协程熔断了")
				// g1 blocked
				time.Sleep(time.Duration(rand.Uint64()%20) * time.Millisecond)
			} else {
				totalPass++
				if rand.Uint64()%20 > 9 {
					totalErr++
					// Record current invocation as error.
					sentinel.TraceError(e, errors.New("biz error"))
				}
				// g1 passed
				time.Sleep(time.Duration(rand.Uint64()%80+10) * time.Millisecond)
				e.Exit()
			}
		}
	}()
	go func() {
		for {
			total++
			e, b := sentinel.Entry("abc")
			if b != nil {
				totalBlock++
				// g2 blocked
				time.Sleep(time.Duration(rand.Uint64()%20) * time.Millisecond)
			} else {
				// g2 passed
				totalPass++
				time.Sleep(time.Duration(rand.Uint64()%80) * time.Millisecond)
				e.Exit()
			}
		}
	}()
	go func() {
		for {
			time.Sleep(time.Second)
			fmt.Println(totalErr)
		}
	}()
	<-ch
}

具体需要修改源码的测试