springcloud H版+alibaba cloud4

19，sleuth链路追踪

sleuth提供了一套完整的服务追踪解决方案
在分布式系统中提供追踪解决方案并且兼容支持zipkin

#springcloud F版本起就不需要自己maven构建zipkin了。只需要调用jar包即可

把jar包下载下来放到一个盘
运行java -jar jar包名

修改服务提供者cloud-provider-payment8001
修改服务消费者cloud-consumer-order80

8001:
pom新增

<!--包含了sleuth+zipkin-->
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-zipkin</artifactId>
</dependency>

yml

zipkin:
  base-url: http://localhost:9411
sleuth:
  sampler:
    probability: 1

controller

@GetMapping("/payment/zipkin")
public String paymentZipkin(){
    return "hi, i'am paymentzipkin server fall back,welcome to atguigu, O(∩_∩)O哈哈~";
}

80
pom和yml一样

controller

//============> zipkin + sleuth
@GetMapping("/consumer/payment/zipkin")
public String paymentZipkin(){
    String result = restTemplate.getForObject("http://localhost:8001" + "/payment/zipkin", String.class);
    return result;
}

启动7001，8001，80,调用80的controller接口形成链路。。。。然后刷新9411的web界面。。。可以看到链路追踪详细信息

20，springcloud alibaba

springcloud alibaba做了一件包饺子的事情

dubbo被springcloud包饺子
cloud又被alibaba cloud包饺子

springcloud alibaba官网
https://github.com/alibaba/spring-cloud-alibaba/blob/master/README-zh.md

springalibaba 支持的功能
服务限流降级
服务注册与发现
分布式配置管理
消息驱动能力：rocketMq
阿里云对象存储
分布式任务调度

如果需要使用springcloud alibaba，则在父工程的root的pom里引入

<dependency>
  <groupId>com.alibaba.cloud</groupId>
  <artifactId>spring-cloud-alibaba-dependencies</artifactId>
  <version>2.1.0.RELEASE</version>
  <type>pom</type>
  <scope>import</scope>
</dependency>

springcloud alibaba的各大组件：

sentinel ,nacos,Rocket,Dubbo,seata,oss,schedulerX

21，nacos

nacos:Naming configuration service

服务注册发现与配置中心服务组件

下载地址：
https://github.com/alibaba/Nacos

官方学习文档也从这进
https://github.com/alibaba/spring-cloud-alibaba/blob/master/README-zh.md

nacos和eureka都是保证AP，高可用和分区容错性。Nacos还保证了cp

1，nacos下载后直接找到bin下的startup.cmd，启动即可

2，访问http://localhost:8848/nacos
用户名，密码都是nacos

                    nacos服务注册与发现

#编码
1，新建项目cloudalibaba-provider-payment9001
2,pom新增

<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
</dependency>

3，yml

server:
  port: 9001

spring:
  application:
    name: nacos-payment-provider
  cloud:
    nacos:
      discovery:
        server-addr: localhost:8848 #配置Nacos地址

management:
  endpoints:
    web:
      exposure:
        include: '*'  #监控

4，主启动类

package com.atguigu.springcloud.alibaba;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
/**
 * @author wsk
 * @date 2020/3/23 10:21
 */
@SpringBootApplication
@EnableDiscoveryClient
public class PaymentMain9001 {
    public static void main(String[] args) {
        SpringApplication.run(PaymentMain9001.class,args);
    }
}

5，主业务类

package com.atguigu.springcloud.alibaba.controller;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
/**
 * @author wsk
 * @date 2020/3/23 10:27
 */
@RestController
public class PaymentController {
    @Value("${server.port}")
    private String serverPort;

    @GetMapping("/payment/nacos/{id}")
    public String getPayment(@PathVariable("id") Integer id){
        return "nacos registry,serverPort: "+ serverPort+"\t id"+id;
    }
}

测试启动9001，访问localhost:9001/payment/nacos/1

                                          nacos负载均衡

1，参照9001新建9002
2，新建微服务消费者83
cloudalibaba-consumer-nacos-order83
pom跟提供者一样

yml

server:
  port: 83

spring:
  application:
    name: nacos-order-consumer
  cloud:
    nacos:
      discovery:
        server-addr: localhost:8848

#消费者将要去访问的微服务名称（成功注册进nacos的微服务提供者），在这配置了访问的服务，业务类就不用在定义常量了

service-url:
  nacos-user-service: http://nacos-payment-provider

主启动类一样
配置类

package com.atguigu.springcloud.alibaba.config;
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;
/**
 * @author wsk
 * @date 2020/3/23 11:07
 */
@Configuration
public class ApplicationContextConfig {
    @Bean
    @LoadBalanced   //RestTemplate结合Ribbon做负载均衡一定要加@LoadBalanced
    public RestTemplate getRestTemplate(){
        return new RestTemplate();
    }
}

业务类

package com.atguigu.springcloud.alibaba.controller;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;
import javax.annotation.Resource;
/**
 * @author wsk
 * @date 2020/3/23 11:09
 */
@RestController
public class OrderNacosController {
    /*
    因为在yml中配置了service-url.nacos-user-service，
    这里不需要再定义要访问微服务名常量，而是通过boot直接读出来
     */
    @Value("${service-url.nacos-user-service}")
    private String serverURL;

    @Resource
    private RestTemplate restTemplate;

    @GetMapping("/consumer/payment/nacos/{id}")
    public String paymentInfo(@PathVariable("id") Long id){
        return restTemplate.getForObject(serverURL+"/payment/nacos/"+id,String.class);
    }
}

启动9002
启动83
然后看nacos

再访问80的接口localhost:83/consumer/

nacos是cp+ap的支持HTTP/DNS/UDP协议的各种支持的强大的组件

#nacos ap和cp的切换
AP模式支持是springcloud，保证了高可用和分区容错性。只支持注册临时实例
CP模式是k8s，保证强一致性和分区容错性

AP和cp可以互相切换
切换命令

curl -X PUT '$NACOS_SERVER:8848/nacos/v1/ns/operator/switches?entry=serverMode&value=CP'

                   nacos配置中心

#编码
1，新建cloudalibaba-config-nacos-client3377
2,pom新增

<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
</dependency>
<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
</dependency>

3，yml 两个
bootstrap.yml

server:
  port: 3377

spring:
  application:
    name: nacos-config-client
  cloud:
    nacos:
      discovery:
        server-addr: localhost:8848 #Nacos服务注册中心地址
      config:
        server-addr: localhost:8848 #Nacos作为配置中心地址
        file-extension: yml

application.yml

spring:
  profiles:
    active: dev #

4,主启动类

package com.atguigu.springcloud.alibaba;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
/**
 * @author wsk
 * @date 2020/3/23 12:28
 */
@SpringBootApplication
@EnableDiscoveryClient
public class NacosConfigClientMain3377 {
    public static void main(String[] args) {
        SpringApplication.run(NacosConfigClientMain3377.class,args);
    }
}

5，业务类

package com.atguigu.springcloud.alibaba.controller;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
/**
 * @author wsk
 * @date 2020/3/23 12:30
 */
@RestController
@RefreshScope   //SpringCloud原生注解 支持Nacos的动态刷新功能
public class ConfigClientController {

    @Value("${config.info}")
    private String configInfo;

    @GetMapping("/config/info")
    public String getConfigInfo(){
        return configInfo;
    }
}

6，在nacos里添加规则
规则是

${spring.application.name}-${spring.profile.active}.${spring.cloud.nacos.config.file-extension}

所以根据以上配置

Data Id   ：nacos-config-client-dev.yml

启动3377，访问localhost:3377/config/info

                                        动态刷新

直接修改nacos配置中心的yaml文件，version改成20，在访问接口

                                        nacos高级篇

nacos对于多环境多项目的管理十分强大，不仅对生产，开发，测试环境都能管理，而且对其他的公司的外包项目的环境也能管理

由nacos的namespace+Group+DataID三者构成
namespace：用于区分部署环境的
Group和DataID用于逻辑上区分两个目标对象

默认情况下：namespace：public
Group:DEFAULT_GROUP
默认的集群cluster也是DEFAULT

Group可以把不同的微服务划分到同一个分组里面去

#######三种配置方式
1,DataId级别的配置
在原基础上再新建一个nacos-config-client-test.yaml
配置内容

config:
    info: from nacos config center,nacos-config-client-test.yaml ,version=2

application.yml里改active改成test就可以访问后面这个新加的配置了

2，group级别的配置
（1）新建配置

DataId： nacos-config-client-info.yaml

Group:DEV_GROUP
配置内容：

config:
    info: nacos-config-client-info.yaml,DEV_GROUP

(2)新建配置

DataId： nacos-config-client-info.yaml
Group:TEST_GROUP

配置内容：

config:
    info: nacos-config-client-info.yaml,TEST_GROUP

（3）修改bootstrap.yml和application.yml
1,bootstrap
config下增加

group: TEST_GROUP

2,application

active: info

重启后访问controller

3，namespace命名空间方案
（1）新建dev/test的namespace
点击命名空间，新建命名空间
dev和test

（2）选择dev 点+号

Dataid ：nacos-config-client-dev.yaml

配置内容：

 config:
    info: xxxxxxxxx  DEFAULT_GROUP

回到bootstrap
group下面配置一行

namespace：  命名空间id

（3）dev下再新建配置

nacos-config-client-dev.yaml
Group: DEV_GROUP

配置内容：

 config:
     info: xxxxxxxxx,DEV-GROUP

(4)dev下再新建配置

nacos-config-client-dev.yaml
Group:TEST_GROUP

配置内容：

config:
       info: xxxxxxxxx,TEST_GROUP

到此为止dev下有三个配置文件。相同命名空间不同组配置
重启服务，访问成功。test命名空间下道理一样不在赘述

                          nocas集群和持久化

8848挂掉了，所有的玩完？
至少得有3台nacos

nocas为什么关闭服务以后。数据还存在。关闭电脑再启动还存在。因为它本身有一个嵌入式数据库，那么有了数据库为什么还要持久化集群mysql？因为多个nacos嵌入式数据库造成数据一致性问题得不到解决

nacos底层源码：
https://github.com/alibaba/nacos/blob/develop/config/pom.xml

默认自带derby嵌入式数据库坐标

derby----mysql的配置
1，nacos-server-1.1.4\nacos\conf目录下找到nacos-mysql.sql
2,到sqlyog执行sql脚本
3，nacos-server-1.1.4\nacos\conf目录下找到application.properties
4，mysql版本在5.6.5以上
application下粘贴

spring.datasource.platform=mysql
db.num=1
db.url.0=jdbc:mysql://127.0.0.1:3306/nacos_config?
characterEncoding=utf8&connectTimeout=1000&socketTimeout=3000&autoReconnect=true

db.user=root
db.password=ljs

5,重启nacos会发现有一个空的页面

6，新建配置

7，发现数据库

                               linux下搭建生产环境下的nacos集群+mysql+nginx

1，下载linux版本的nacos
https://github.com/alibaba/nacos/releases/tag/1.1.4
跟之前windows的一样也是找到sql文件。然后复制到linux的数据库下。然后修改配置文件。。

直接参考这篇文章。。。https://www.cnblogs.com/larscheng/p/11427733.html

代码实例

修改9002 nacos的服务提供者yml文件

注册成功。nacos

22，sentinel

alibaba sentinel 实现熔断和限流

#官方文档
github.com/alibaba/sentinel

之前的hystrix
1，需要自己手工搭建监控平台
2，没有web界面可给我们进行更加细粒化的配置
以及流控，速率控制。服务熔断，服务降级

sentinel:
1,单独一个组件，可独立出来
2，直接姐棉花细粒度统一配置

下载地址：https://github.com/alibaba/sentinel/releases
下载1.7的sentinel-dashboard.jar

sentinal分为两个部分：
核心库：（java客户端）不依赖任何框架/库。能够运行于所有java运行时环境。对dubbo/springcloud框架也有很好的支持

控制台：基于springboot开发。打包后可直接运行不需要额外的tomcat等应用容器

运行jar包以后访问localhost:8080

用户名密码都是sentinel

                     sentinel的初始化监控

#编码
1，启动nacos8848

2，新建cloud-alibaba-sentinel-service 8401

3，pom

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

4，yml

server:
  port: 8401
spring:
  application:
    name: cloudalibaba-sentinel-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
        # 默认为8719，如果被占用会自动+1，直到找到为止
        port: 8719
management:
  endpoints:
    web:
      exposure:
        include: "*"      

5，主启动类

package com.atguigu.springcloud.alibaba;
        import org.springframework.boot.SpringApplication;
        import org.springframework.boot.autoconfigure.SpringBootApplication;
        import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
/**
 * @author wsk
 * @date 2020/3/24 13:59
 */
@SpringBootApplication
@EnableDiscoveryClient
public class MainApp8401 {
    public static void main(String[] args) {
        SpringApplication.run(MainApp8401.class,args);
    }
}

6，controller

package com.atguigu.springcloud.alibaba.controller;
import com.alibaba.csp.sentinel.annotation.SentinelResource;
import com.alibaba.csp.sentinel.slots.block.BlockException;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
/**
 * @author wsk
 * @date 2020/3/24 14:00
 */
@RestController
@Slf4j
public class FlowLimitController {

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

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

7，启动8401
访问接口http://localhost:8401/testA

                                    sentinel 流控规则

流量控制：
资源名就是我们的application -name
唯一的。或者默认请求路径

针对来源就是：sentinel可以针对调用者进行限流。填写微服务名。默认default

阈值类型/单机阈值
qps：当调用该api的qps达到阈值的时候，进行限流
线程数：当调用该api的线程数达到阈值的时候进行限流
是否集群：sentinel不需要

流控模式
直接：api达到限流条件时，直接限流
关联：当关联资源达到阈值，限流自己
链路：只记录指定链路上的流量

流控效果：
快速失败：直接失败，抛异常
warm up：根据codeFactor（冷加载因子。默认3）的值，从阈值codeFactor，经过预热时长，才达到设置的qps值
排队等待：匀速排队，让请求以匀速的速度通过，阈值类型必须为qps，否则无效

                      流控模式

1，qps：
设置单机阈值 1
流控模式：直接
流控效果：快速失败

快速点击

2，线程数
在sentinel设置

然后回到testA修改testA方法

@GetMapping("/testA")
public String testA(){
    try{
        TimeUnit.MILLISECONDS.sleep(800);
    } catch (InterruptedException e) {
        e.printStackTrace();
    }
    return "--------testA";
}

然后开两个浏览器模拟多线程

流控模式：1，关联
相当于我生病，你吃药？这有什么用？
#通常用于支付模块达到阈值，限流订单模块。

配置规则
testA
阈值类型qps 单机阈值1
流控模式：关联
关联资源：/testB
流控效果：快速失败
打开postman 模拟多线程访问testB

找到collections

模拟20个线程，每延迟300毫秒访问testB

这期间访问testA

这之后访问

流控效果：default
直接失败：抛出异常

Blocked by sentinel(flow limiting)

                     流控效果：预热：warm up

设置 资源名：/testB
针对来源：default
阈值类型：qps 单机阈值10
预热时长 5 流程模式：直接

在5秒钟阈值慢慢从3-10
访问浏览器很快刷新页面。刚开始不行。慢慢过了5秒的样子能抗住了

如秒杀系统在开启的瞬间，会有很多流量上来。很有可能把系统打死。预热方式就是为了保护系统，慢慢将流量放进来。慢慢把阈值增长到设置的阈值

冷加载因子=单机阈值/3
根据warm up 设置时间慢慢qps由单机阈值/3-----单机阈值

                      流程效果：排队等待

让请求以均匀的速度通过，阈值类型必须设置成qps否则无效
设置：资源名：/testA
阈值类型：qps 单机阈值：1
流控模式：直接
流控效果：排队等待
超时时间：20000

意思是：/testA每秒1次请求。超过就排队等待，等待的超时时间为20000毫秒

相当于在某一秒有大量请求。接下来空闲。一会又有大量请求。我们可以在空闲时间处理剩下的请求。而不是在第一秒就直接拒绝了

回到idea在testB方法里加

log.info(Thread.currentThread().getName()+"\t"+"...testB");

                                   sentinel降级

点击降级规则，右上角–+新增降级规则
有三种策略：RT,异常比例，异常数

RT：平均响应时间：秒级
平均响应时间超出阈值，且时间窗口内通过的请求>=5两个条件同时满足触发降级。窗口期过后关闭断路器。RT最大为4900

异常比例：秒级
qps>=5且异常比例（秒级）超过阈值。触发降级。时间窗口结束后。关闭降级

异常数（分钟级）
异常数（分钟统计）超过阈值时。触发降级，时间窗口结束后，关闭降级

sentinel 熔断降级会在调用链路中某个资源出现不稳定状态时候（例如调用超时或异常比例升高），对这个资源的调用进行限制。让请求快速失败。避免影响到其他资源导致级联错误

当资源被降级后，在接下来降级时间窗口内。对该资源的调用都自动熔断。默认抛出DegradeException

Hystrix有open closed halfopen状态
sentinel没有半开状态

1，RT
平均响应时间：1秒持续5个请求。且平均响应时间大于阈值，触发降级。时间窗口期结束。关闭降级

回到controller

@GetMapping("/testD")
public String testD(){
    try {
        TimeUnit.SECONDS.sleep(1);
    } catch (InterruptedException e) {
        e.printStackTrace();
    }
    log.info("testD 测试 RT");
    return "--------testD";
}

回到sentinel dashboard —簇点链路–选择降级–选RT–RT200–时间窗口1

使用jmeter压测

线程数设置10

Ramp-up perviod(in seconds):1
循环次数：永远

启动项目，再启动jmeter

再访问接口localhost:8401/testD
会出现降级

#为什么会这样呢？
根据jmeter的设置。永远一秒打进10个线程。大于5个。调用testD。我们希望200ms处理完本次任务。如果超过200ms没有处理完。在未来一秒钟内的时间窗口内。断路器打开。微服务不可用

2，异常比例
异常比例：当资源的每次请求量>=5，并且每秒异常总数占通过量比值超过阈值之后。资源进入降级状态，即在接下的时间窗口内，对这个方法调用都会自动地返回。异常比例的阈值范围在[0.0，1.0]。0%-100%

qps>=5&&异常比例超过阈值，触发降级，时间窗口期结束，关闭降级

将/testD代码改为。。

@GetMapping("/testD")
public String testD(){
    log.info("testD 测试 RT");
    int age=10/0;
    return "--------testD";
}

sentinel的设置
异常比例-0.2–时间窗口1

jmeter依旧和刚才一样设置跑起来

停掉jmeter

3，异常数
异常数：当资源近一分钟的异常数目超过阈值之后会进行熔断：时间窗口一定大于60秒。因为它是分钟级的

异常数超过阈值—降级—时间窗口结束----关闭降级

controller

@GetMapping("/testE")
public String testE(){
    log.info("testE测试异常数");
    int age = 10/0;
    return "--------testE 测试异常数";
}

sentinel设置—异常数–5--时间窗口61

访问localhost:8401/testE
访问5次以后才触发降级

                  sentinel热点key限流

官网：github.com/alibaba/sentinel/wiki/热点参数限流

像hystrix某个方法出问题了，去找对应兜底方法降级。这是我们自定义的

像sentinel不配置的话。默认提示Blocked by sentinel(flow limiting)

可以配置Sentinel的@SentinelResource

热点限流key的原理
官网源码：com.alibaba.csp.sentinel.slots.block.BlockException

#编码
controller

@GetMapping("/testHotKey")
@SentinelResource(value = "testHotKey",blockHandler = "deal_testHotKey")
public String testHotKey(@RequestParam(value = "p1",required = false) String p1,
                         @RequestParam(value = "p2",required = false) String p2){
    return "testHotKey";
}
public String deal_testHotKey(String p1, String p2, BlockException exception){
    return "---------------deal_testHotKey,o(╥﹏╥)o";
}

sentinel设置热点限流规则
资源名：testHotKey
参数索引：0
单机阈值：1
窗口时长：1

正常访问

点击速度加快

#如果用了@SentinelResource一定要指定value的同时，指定blockhandler否则会有异常页面。用户看到不太好

                   热点key参数例外项

在编辑热点规则下面有个高级选项

当我们设定了p1这个参数为0的索引。一旦qps>1则熔断限流。可不可以p1的值如果等于一个特定的值。则让他不熔断限流呢

设置参数例外项。记得不要忘记添加按钮

参数类型只能支持String加8种基本数据类型
参数值：5
限流阈值：200
添加

然后访问接口

如果在testHotKey方法添加一行代码：
int age=10/0;

所以直接的@SentinelResource不管运行时异常

                     系统自适应限流

sentinel
点击系统规则—新增系统规则
load自适应
只支持linux，unix系统。

如果设置了入口qps则掌握全局qps阈值设置1

  #####           SentinelResource配置

1，按资源名称限流+后续处理
#编码
（1）修改pom
增加一个

<dependency>
    <groupId>com.atguigu.springcloud</groupId>
    <artifactId>cloud-api-commons</artifactId>
    <version>${project.version}</version>
</dependency>

（2）新建controller
@RestController

public class RateLimitController {

    @GetMapping("/byResource")
    @SentinelResource(value = "byResource",blockHandler = "handlerException")
    public CommonResult byResource(){
        return new CommonResult(200,"按资源名称限流测试OK",new Payment(2020L,"serial001"));
    }
    public CommonResult handlerException(BlockException exception){
        return new CommonResult(444,exception.getClass().getCanonicalName()+"\t 服务不可用");
    }
    }

（3）sentinel–流控规则–新建资源名byResource-阈值类型qps-单机阈值1

启动nacos，sentinel，8401项目
访问localhost:8401/byResource狂点会进入兜底

正常点。正常访问

平时关闭8401微服务。流控规则会消失。所以它是临时节点

2，按照url地址限流

在controller增加一个方法
@GetMapping("/rateLimit/byUrl")
@SentinelResource(value=“byUrl”)
public CommonResult byurl(){
return new CommonResult(200,“按url限流ok”,new Payment(2020L,“Serial002”));
}

这个sentinel设置直接加一个左斜杠

不好用就去掉斜杠，好用了
，但是没有指定blockHandler肯定刷快了会爆异常页面

3，兜底方法存在问题
每个业务都有一个兜底方法，像hystrix一样，可以解耦。写一个fallback类？可以！

客户自定义限流
（1）创建CustomerBlockHandler类

package com.atguigu.springcloud.alibaba.handler;
import com.alibaba.csp.sentinel.slots.block.BlockException;
import com.atguigu.springcloud.entities.CommonResult;
import com.atguigu.springcloud.entities.Payment;
/**
 * @author wsk
 * @date 2020/3/24 22:04
 */
public class CustomerBlockHandler {

    public static CommonResult handlerException(BlockException exception){
        return new CommonResult(4444,"按客户自定义，global handlerException-----1");
    }
    public static CommonResult handlerException2(BlockException exception){
        return new CommonResult(4444,"按客户自定义，global handlerException-----2");
    }
}

（2）RatelimitController添加方法

@GetMapping("/rateLimit/customerBlockHandler")
@SentinelResource(value = "customerBlockHandler",
        blockHandlerClass = CustomerBlockHandler.class,
        blockHandler = "handlerException2")
public CommonResult customerBlockHandler(){
    return new CommonResult(200,"按客户自定义",new Payment(2020L,"serial002"));
}

启动8401

访问这个接口

然后设置sentinel

平时访问

兜底访问

sentinel熔断
sentinel注解不支持private只支持public

服务熔断采取整合ribbon或openFeign+fallback

1，修改cloudalibaba-provider-payment9003/9004

package com.atguigu.springcloud.controller;
import com.atguigu.springcloud.entities.CommonResult;
import com.atguigu.springcloud.entities.Payment;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import java.util.HashMap;
/**
 * @author wsk
 * @date 2020/3/24 22:36
 */
@RestController
public class PaymentController {

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

    public static HashMap<Long, Payment> hashMap = new HashMap<>();
    static {
        hashMap.put(1L,new Payment(1L,"28adsasadsafas5d1as5fad5as31d3as0"));
        hashMap.put(2L,new Payment(2L,"4das5d5asda4dad5asda5s3dasd53das0"));
        hashMap.put(3L,new Payment(3L,"6ads65d351as3d1as53d1a53d3as13as0"));
    }

    @GetMapping("/paymentSQL/{id}")
    public CommonResult<Payment> paymentSQL(@PathVariable("id") Long id){
        Payment payment = hashMap.get(id);
        CommonResult<Payment> result = new CommonResult(200, "from mysql ,serverPort: " + serverPort);
        return result;
    }
}

2，84作为消费者端调9003/9004实现负载均衡
修改84
第一种情况。没有任何配置的

package com.atguigu.springcloud.controller;

import com.alibaba.csp.sentinel.annotation.SentinelResource;
import com.alibaba.csp.sentinel.slots.block.BlockException;
import com.atguigu.springcloud.entities.CommonResult;
import com.atguigu.springcloud.entities.Payment;
import com.atguigu.springcloud.service.PaymentService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

import javax.annotation.Resource;

/**
 * @author wsk
 * @date 2020/3/24 23:06
 */
@RestController
@Slf4j
public class CircleBreakerController {
    private static final String SERVICE_URL = "http://nacos-payment-provider";

    @Resource
    private RestTemplate restTemplate;

    @RequestMapping("/consumer/fallback/{id}")
   @SentinelResource(value = "fallback") //没有配置
//    @SentinelResource(value = "fallback",fallback = "handlerFallback") //配置了fallback的，fallback只负责业务异常
//    @SentinelResource(value = "fallback",blockHandler = "blockHandler") // 配置了blockHandler，只负责sentinel控制台配置违规
    //@SentinelResource(value = "fallback",fallback = "handlerFallback", blockHandler = "blockHandler",
         //   exceptionsToIgnore = {IllegalArgumentException.class}) // 配置了blockHandler和fallback
    public CommonResult<Payment> fallback(@PathVariable("id") Long id){
        CommonResult<Payment> commonResult = restTemplate.getForObject(SERVICE_URL + "/paymentSQL/" + id, CommonResult.class);
        if(id == 4){
            throw new IllegalArgumentException("IllegalArgumentException,非法参数异常");
        }else if(commonResult.getData() == null){
            throw new NullPointerException("NullPointerException,该ID没有记录，空指针异常");
        }
        return commonResult;
    }
    // 本例是fallback
    public CommonResult handlerFallback(Long id, Throwable e){
        Payment payment = new Payment(id, null);
        return new CommonResult(444, "兜底异常handler，exception内容"+e.getMessage(), payment);
    }

    public CommonResult blockHandler(Long id, BlockException exception){
        Payment payment = new Payment(id, null);
        return new CommonResult<>(445, "blockHandler-sentinel 限流，无此流水号：blockException" + exception.getMessage(), payment);
    }

    // --------------- open feign---------

    @Resource
    private PaymentService paymentService;

    @GetMapping("/consumer/paymentSQL/{id}")
    public CommonResult<Payment> paymentSQL(@PathVariable("id") Long id){
        return paymentService.paymentSQL(id);
    }
}

3，启动nacos，sentinel，9003，9004，84
测试http://localhost:84/consumer/fallback

如果是4，报页面的非法参数异常。。。。

4以外的报空指针异常

第二种情况
@SentinelResource(value = “fallback”,fallback = “handlerFallback”)

加代码。方法

// 本例是fallback
public CommonResult handlerFallback(Long id, Throwable e){
    Payment payment = new Payment(id, null);
    return new CommonResult(444, "兜底异常handler，exception内容"+e.getMessage(), payment);
}

第三种情况

@SentinelResource(value = "fallback",blockHandler = "blockHandler")

加代码

public CommonResult blockHandler(Long id, BlockException exception){
      Payment payment = new Payment(id, null);
      return new CommonResult<>(445, "blockHandler-sentinel 限流，无此流水号：blockException" + exception.getMessage(), payment);
  }

设置sentinel

然后访问接口方法

多访问几次进入兜底

第四种情况

@SentinelResource(value = "fallback",fallback = "handlerFallback", blockHandler = "blockHandler")

放开刚才两个方法
sentinel设置流控规则
qps：1
访问接口。

快速点击进入限流

普通点击走兜底

快速点击fallback4，是走兜底还是限流。是走限流的

异常忽略属性

@SentinelResource(value = "fallback",fallback = "handlerFallback", blockHandler = "blockHandler",
       exceptionsToIgnore = {IllegalArgumentException.class})

然后访问localhost:84/consumer/fallback/4

走的是error page

localhost:84/consumer/fallback/5

走的兜底

                      sentinel服务熔断+openfeign

修改84.
1，pom
新增

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>

2，yml
#激活sentinel对feign的支持

feign:
  sentinel:
    enabled: true

3，主启动类

@SpringBootApplication
@EnableDiscoveryClient
@EnableFeignClients

4，service

package com.atguigu.springcloud.service;
import com.atguigu.springcloud.entities.CommonResult;
import com.atguigu.springcloud.entities.Payment;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
/**
 * @author wsk
 * @date 2020/3/25 9:02
 */
@FeignClient(value = "nacos-payment-provider",fallback = PaymentFallbackService.class)
public interface PaymentService {

    @GetMapping("/paymentSQL/{id}")
    public CommonResult<Payment> paymentSQL(@PathVariable("id") Long id);
}

package com.atguigu.springcloud.service;
import com.atguigu.springcloud.entities.CommonResult;
import com.atguigu.springcloud.entities.Payment;
import org.springframework.stereotype.Component;

/**
 * @author wsk
 * @date 2020/3/25 9:06
 */
@Component
public class PaymentFallbackService implements PaymentService{
    @Override
    public CommonResult<Payment> paymentSQL(Long id) {
        return new CommonResult<>(444,"服务降级返回，------------PaymentFallbackService",new Payment(id,"errorSerial"));
    }
}

5，controller

// --------------- open feign---------

  @Resource
  private PaymentService paymentService;

  @GetMapping("/consumer/paymentSQL/{id}")
  public CommonResult<Payment> paymentSQL(@PathVariable("id") Long id){
      return paymentService.paymentSQL(id);
  }

故意关闭9003

触发降级

                sentinel持久化

当我们配置规则以后，关闭服务。配置规则自动消失。
将限流，熔断这些配置规则持久化进nacos。只要刷新8401某个rest地址。sentinel控制台的流控规则就可以看到。只要nacos里面配置不删除。针对8401上sentinel上的流控规则持续有效

1，修改cloudalibaba-sentinel-service8401
pom新增

<!--springcloud alibaba sentinel-datasource-nacos 后续做持久化用到-->
<dependency>
    <groupId>com.alibaba.csp</groupId>
    <artifactId>sentinel-datasource-nacos</artifactId>
</dependency>

2，yml

server:
  port: 8401
spring:
  application:
    name: cloudalibaba-sentinel-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
        # 默认为8719，如果被占用会自动+1，直到找到为止
        port: 8719
      # 流控规则持久化到nacos
      datasource:
        dsl:
          nacos:
            server-addr: localhost:8848
            data-id: ${spring.application.name}
            group-id: DEFAULT_GROUP
            data-type: json
            rule-type: flow
management:
  endpoints:
    web:
      exposure:
        include: "*"
feign:
  sentinel:
    enabled: true        

3，添加nacos业务规则配置（必须是做了持久化的nacos）
可以用本地的8848 nacos配置

新建配置
DataID：cloudalibaba-sentinel-service
配置格式：json
配置内容：

[
    {
        "resource":"/rateLimit/byUrl",
        "limitApp":"default",
        "grade":1,
        "count":1,
        "strategy":0,
        "controllBehavior":0,
        "clusterMode":false
    }
]

其中各项含义：
resource：资源名称
limitApp：来源应用
grade：阈值类型 0，线程数 1，qps
count：单机阈值
strategy：流控模式，0直接 1关联 2链路
controlBehavior:流程效果 0快速失败 1warm up 2排队等待
clusterMode 是否集群

4，启动8401，访问接口。刷新sentinel发现流控规则有了

停止8401发现
没了

不怕，再重启8401

快速访问刚才那个localhost:8401/rateLimit/byUrl

我并没有重新配置流控。他快速访问就已经生效。说明。sentinel持久化成功

23，seata

seata处理分布式事务

以前的单体应用被拆分成多个应用，分别使用多个独立的数据源（数据库），每个服务内部数据的一致性由本地事务来保证，但全局无法保证，所以出现了分布式事务

一次业务操作需要跨多个数据源或需要跨多个系统进行远程调用，就会产生分布式事务问题

seata是alibaba开源的分布式事务解决方案。致力于在微服务架构下提供高性能和简单易用的分布式事务服务

官网http://seata.io/zh-cn/

全局唯一事务id+三组件（TC,TM,RM）

TC：事务协调器，维护全局事务运行状态，负责协调并驱动全局事务提交或回滚
TM：控制全局事务的边界。负责开启一个全局事务，并最终发起全局提交式全局回滚的决议
RM：控制分支事务，负责分支注册，状态汇报，并接受事务协调器指令，驱动本地事务提交和回滚

seata分布式事务执行原理
1，TM向TC申请开启一个全局事务，全局事务创建成功并生成一个全局唯一的XID
2，XID在微服务调用链路的上下文中传播
3，RM向TC注册分支事务，将其纳入XID对应全局事务的管辖
4，TM向TC发起针对XID的全局提交或回滚决议
5，TC调度XID下管辖的全部后支事务完成提交或回滚请求

                      seata安装配置

1，地址：https://github.com/seata/seata/releases

2,解压到固定的路径
3,修改：自定义事务组名称+事务日志存储模式db+数据库连接信息
4，修改conf下的file.conf
(1)修改service里的

 vgroup_mapping.my_test_tx_group = "fsp_tx_group"

(2)修改store模块的

mode="db"

然后下面改db的配置

url="jdbc:mysql://127.0.0.1:3306/seata"
user="root"
password="ljs"

5，在数据库新建库seata
6，在seata库里建表
建表sql在\seata-server-1.0.0\seata\conf里
db_store.sql

drop table if exists `global_table`;
create table `global_table` (
  `xid` varchar(128)  not null,
  `transaction_id` bigint,
  `status` tinyint not null,
  `application_id` varchar(32),
  `transaction_service_group` varchar(32),
  `transaction_name` varchar(128),
  `timeout` int,
  `begin_time` bigint,
  `application_data` varchar(2000),
  `gmt_create` datetime,
  `gmt_modified` datetime,
  primary key (`xid`),
  key `idx_gmt_modified_status` (`gmt_modified`, `status`),
  key `idx_transaction_id` (`transaction_id`)
);


drop table if exists `branch_table`;
create table `branch_table` (
  `branch_id` bigint not null,
  `xid` varchar(128) not null,
  `transaction_id` bigint ,
  `resource_group_id` varchar(32),
  `resource_id` varchar(256) ,
  `lock_key` varchar(128) ,
  `branch_type` varchar(8) ,
  `status` tinyint,
  `client_id` varchar(64),
  `application_data` varchar(2000),
  `gmt_create` datetime,
  `gmt_modified` datetime,
  primary key (`branch_id`),
  key `idx_xid` (`xid`)
);


drop table if exists `lock_table`;
create table `lock_table` (
  `row_key` varchar(128) not null,
  `xid` varchar(96),
  `transaction_id` long ,
  `branch_id` long,
  `resource_id` varchar(256) ,
  `table_name` varchar(32) ,
  `pk` varchar(36) ,
  `gmt_create` datetime ,
  `gmt_modified` datetime,
  primary key(`row_key`)
);

分支，全局，锁表生成成功

7，修改seata-server-1.0.0\seata\conf目录下的registry.conf配置文件
第三行

type="nacos"
然后找到nacos{
serverAddr="localhost:8848"

8,启动nacos，再启动seata-server.bat。如果dos下出现

表示内存不足。要找到
seata-server.bat里修改

改成这样，改小

-load Registry Provider表示执行成功

            订单/库存/账户数据库准备

都需要先启动nacos，再启动seata
业务：当用户下单时，会在订单服务中创建一个订单。然后通过远程调用库存服务扣减下单商品的库存，再通过远程调用账户服务来扣减用户账户里面的余额。最后订单服务中修改订单状态为已完成

创建业务数据库
seata-order:存储订单的数据库
seata-storage:存储库存的数据库
seata-account:存储账户信息的数据库
库对应表：
order库对应t_order表
storage库对应t_storage表
account库对应t_account表

订单，库存，账户3个库下都需要建各自的回滚日志表
在\seata-server-1.0.0\seata\conf目录下有
db_undo_log.sql

CREATE TABLE `undo_log` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `branch_id` bigint(20) NOT NULL,
  `xid` varchar(100) NOT NULL,
  `context` varchar(128) NOT NULL,
  `rollback_info` longblob NOT NULL,
  `log_status` int(11) NOT NULL,
  `log_created` datetime NOT NULL,
  `log_modified` datetime NOT NULL,
  `ext` varchar(100) DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `ux_undo_log` (`xid`,`branch_id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

在三个库下分别粘贴执行

最终的数据库准备结果

订单。库存。账户微服务编码
下订单–减库存—减余额–改订单状态

订单模块。创建seata-order-service2001
1，pom

<?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>cloud2020</artifactId>
        <groupId>com.atguigu.springcloud</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>seata-order-service2001</artifactId>

    <dependencies>
        <!--nacos-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>
        <!--seata-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-seata</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>io.seata</groupId>
                    <artifactId>seata-all</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>io.seata</groupId>
            <artifactId>seata-all</artifactId>
            <version>1.0.0</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.1.10</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <!--jdbc-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <!--hutool 测试雪花算法-->
        <dependency>
            <groupId>cn.hutool</groupId>
            <artifactId>hutool-captcha</artifactId>
            <version>5.2.0</version>
        </dependency>
    </dependencies>
</project>

2，yml

server:
  port: 2001

spring:
  application:
    name: seata-order-service
  cloud:
    alibaba:
      seata:
        # 自定义事务组名称需要与seata-server中的对应
        tx-service-group: fsp_tx_group
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848
  datasource:
    # 当前数据源操作类型
    type: com.alibaba.druid.pool.DruidDataSource
    # mysql驱动类
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://47.115.93.213:3306/seata_order?useUnicode=true&characterEncoding=UTF-8&useSSL=false&serverTimezone=GMT%2B8
    username: root
    password: ljs
feign:
  hystrix:
    enabled: false
logging:
  level:
    io:
      seata: info
#ribbon的超时时间,这里测试用
ribbon:
   ReadTimeout: 60000
   ConnectTimeout: 60000

mybatis:
  mapper-locations: classpath*:mapper/*.xml

3，file.conf

transport {
  # tcp udt unix-domain-socket
  type = "TCP"
  #NIO NATIVE
  server = "NIO"
  #enable heartbeat
  heartbeat = true
  #thread factory for netty
  thread-factory {
    boss-thread-prefix = "NettyBoss"
    worker-thread-prefix = "NettyServerNIOWorker"
    server-executor-thread-prefix = "NettyServerBizHandler"
    share-boss-worker = false
    client-selector-thread-prefix = "NettyClientSelector"
    client-selector-thread-size = 1
    client-worker-thread-prefix = "NettyClientWorkerThread"
    # netty boss thread size,will not be used for UDT
    boss-thread-size = 1
    #auto default pin or 8
    worker-thread-size = 8
  }
  shutdown {
    # when destroy server, wait seconds
    wait = 3
  }
  serialization = "seata"
  compressor = "none"
}
service {
  #vgroup->rgroup
  # 事务组名称
  vgroup_mapping.fsp_tx_group = "default"
  #only support single node
  default.grouplist = "127.0.0.1:8091"
  #degrade current not support
  enableDegrade = false
  #disable
  disable = false
  #unit ms,s,m,h,d represents milliseconds, seconds, minutes, hours, days, default permanent
  max.commit.retry.timeout = "-1"
  max.rollback.retry.timeout = "-1"
}

client {
  async.commit.buffer.limit = 10000
  lock {
    retry.internal = 10
    retry.times = 30
  }
  report.retry.count = 5
  tm.commit.retry.count = 1
  tm.rollback.retry.count = 1
}

## transaction log store
store {
  ## store mode: file、db
  #mode = "file"
  mode = "db"

  ## file store
  file {
    dir = "sessionStore"

    # branch session size , if exceeded first try compress lockkey, still exceeded throws exceptions
    max-branch-session-size = 16384
    # globe session size , if exceeded throws exceptions
    max-global-session-size = 512
    # file buffer size , if exceeded allocate new buffer
    file-write-buffer-cache-size = 16384
    # when recover batch read size
    session.reload.read_size = 100
    # async, sync
    flush-disk-mode = async
  }

  ## database store
  db {
    ## the implement of javax.sql.DataSource, such as DruidDataSource(druid)/BasicDataSource(dbcp) etc.
    datasource = "dbcp"
    ## mysql/oracle/h2/oceanbase etc.
    db-type = "mysql"
    driver-class-name = "com.mysql.jdbc.Driver"
    url = "jdbc:mysql://47.115.93.213:3306/seata"
    user = "root"
    password = "ljs"
    min-conn = 1
    max-conn = 3
    global.table = "global_table"
    branch.table = "branch_table"
    lock-table = "lock_table"
    query-limit = 100
  }
}
lock {
  ## the lock store mode: local、remote
  mode = "remote"

  local {
    ## store locks in user's database
  }

  remote {
    ## store locks in the seata's server
  }
}
recovery {
  #schedule committing retry period in milliseconds
  committing-retry-period = 1000
  #schedule asyn committing retry period in milliseconds
  asyn-committing-retry-period = 1000
  #schedule rollbacking retry period in milliseconds
  rollbacking-retry-period = 1000
  #schedule timeout retry period in milliseconds
  timeout-retry-period = 1000
}

transaction {
  undo.data.validation = true
  undo.log.serialization = "jackson"
  undo.log.save.days = 7
  #schedule delete expired undo_log in milliseconds
  undo.log.delete.period = 86400000
  undo.log.table = "undo_log"
}

## metrics settings
metrics {
  enabled = false
  registry-type = "compact"
  # multi exporters use comma divided
  exporter-list = "prometheus"
  exporter-prometheus-port = 9898
}

support {
  ## spring
  spring {
    # auto proxy the DataSource bean
    datasource.autoproxy = false
  }
}

4,regustry.conf

registry {
  # file 、nacos 、eureka、redis、zk、consul、etcd3、sofa
  type = "nacos"

  nacos {
    #serverAddr = "localhost"
    serverAddr = "localhost:8848"
    namespace = ""
    cluster = "default"
  }
  eureka {
    serviceUrl = "http://localhost:8761/eureka"
    application = "default"
    weight = "1"
  }
  redis {
    serverAddr = "localhost:6379"
    db = "0"
  }
  zk {
    cluster = "default"
    serverAddr = "127.0.0.1:2181"
    session.timeout = 6000
    connect.timeout = 2000
  }
  consul {
    cluster = "default"
    serverAddr = "127.0.0.1:8500"
  }
  etcd3 {
    cluster = "default"
    serverAddr = "http://localhost:2379"
  }
  sofa {
    serverAddr = "127.0.0.1:9603"
    application = "default"
    region = "DEFAULT_ZONE"
    datacenter = "DefaultDataCenter"
    cluster = "default"
    group = "SEATA_GROUP"
    addressWaitTime = "3000"
  }
  file {
    name = "file.conf"
  }
}

config {
  # file、nacos 、apollo、zk、consul、etcd3
  type = "file"

  nacos {
    serverAddr = "localhost"
    namespace = ""
  }
  consul {
    serverAddr = "127.0.0.1:8500"
  }
  apollo {
    app.id = "seata-server"
    apollo.meta = "http://192.168.1.204:8801"
  }
  zk {
    serverAddr = "127.0.0.1:2181"
    session.timeout = 6000
    connect.timeout = 2000
  }
  etcd3 {
    serverAddr = "http://localhost:2379"
  }
  file {
    name = "file.conf"
  }
}

5,domain
CommonResult

package com.atguigu.springcloud.alibaba.domain;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
/**
 * @author wsk
 * @date 2020/3/25 20:37
 */
@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);
    }
}

Order

package com.atguigu.springcloud.alibaba.domain;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.math.BigDecimal;
/**
 * @author wsk
 * @date 2020/3/25 20:25
 */
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Order {
    private Long id;
    private Long userId;
    private Long productId;
    private Integer count;
    private BigDecimal money;
    private Integer status;
}

6,dao

package com.atguigu.springcloud.alibaba.dao;
import com.atguigu.springcloud.alibaba.domain.Order;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
/**
 * @author wsk
 * @date 2020/3/25 20:41
 */
@Mapper
public interface OrderDao {
    //1 新建订单
    void createOrder(Order order);

    //2 修改订单状态 从0改为1
    void update(@Param("userId") Long userId,@Param("status") Integer status);
}

7,xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.atguigu.springcloud.alibaba.dao.OrderDao">

    <resultMap id="BaseResultMap" type="com.atguigu.springcloud.alibaba.domain.Order">
        <id column="id" property="id" jdbcType="BIGINT"></id>
        <result column="user_id" property="userId" jdbcType="BIGINT"></result>
        <result column="product_id" property="productId" jdbcType="BIGINT"></result>
        <result column="count" property="count" jdbcType="INTEGER"></result>
        <result column="money" property="money" jdbcType="DECIMAL"></result>
        <result column="status" property="status" jdbcType="INTEGER"></result>
    </resultMap>

    <insert id="createOrder" parameterType="com.atguigu.springcloud.alibaba.domain.Order" useGeneratedKeys="true"
            keyProperty="id">
        insert into t_order(user_id,product_id,count,money,status) values (#{userId},#{productId},#{count},#{money},0);
    </insert>

    <update id="update">
        update t_order set status =1 where user_id =#{userId} and status=#{status};
    </update>
</mapper>

8,service
orderService

package com.atguigu.springcloud.alibaba.service;

import com.atguigu.springcloud.alibaba.domain.Order;

/**
 * @author wsk
 * @date 2020/3/25 20:58
 */
public interface OrderService {
    void create(Order order);


}

StorageService

package com.atguigu.springcloud.alibaba.service;

import com.atguigu.springcloud.alibaba.domain.CommonResult;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;

/**
 * @author wsk
 * @date 2020/3/25 21:00
 */
@FeignClient(value = "seata-storage-service")
public interface StorageService {

    @PostMapping(value = "/storage/decrease")
    CommonResult decrease(@RequestParam("productId") Long productId,@RequestParam("count") Integer count);
}

AccountService

package com.atguigu.springcloud.alibaba.service;
import com.atguigu.springcloud.alibaba.domain.CommonResult;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;
import java.math.BigDecimal;

/**
 * @author wsk
 * @date 2020/3/25 21:00
 */
@FeignClient(value = "seata-account-service")
public interface AccountService {

    @PostMapping(value = "/account/decrease")
    CommonResult decrease(@RequestParam("userId") Long userId,@RequestParam("money") BigDecimal money);
}

9,serviceImpl

package com.atguigu.springcloud.alibaba.service.impl;
import com.atguigu.springcloud.alibaba.dao.OrderDao;
import com.atguigu.springcloud.alibaba.domain.Order;
import com.atguigu.springcloud.alibaba.service.AccountService;
import com.atguigu.springcloud.alibaba.service.OrderService;
import com.atguigu.springcloud.alibaba.service.StorageService;
import io.seata.spring.annotation.GlobalTransactional;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Service;
import javax.annotation.Resource;

/**
 * @author wsk
 * @date 2020/3/25 20:59
 */
@Service
@Slf4j
public class OrderServiceImpl implements OrderService {

    @Resource
    private OrderDao orderDao;
    @Resource
    private AccountService accountService;
    @Resource
    private StorageService storageService;

    /**
     * 创建订单->调用库存服务扣减库存->调用账户服务扣减账户余额->修改订单状态
     * 简单说:
     * 下订单->减库存->减余额->改状态
     * GlobalTransactional seata开启分布式事务,异常时回滚,name保证唯一即可
     */
    @Override
    @GlobalTransactional(name = "fsp-create-order",rollbackFor = Exception.class)
    public void create(Order order) {
        log.info("----->开始创建新订单");
        //1 新建订单
        orderDao.createOrder(order);

        log.info("----->订单微服务开始调用库存，做扣减Count");
        //2 扣减库存
        storageService.decrease(order.getProductId(),order.getCount());
        log.info("----->订单微服务开始调用库存，做扣减end");

        log.info("----->订单微服务开始调用账户，做扣减Money");
        //3 扣减账户
        accountService.decrease(order.getUserId(),order.getMoney());
        log.info("----->订单微服务开始调用库存，做扣减end");

        //修改订单状态，从0到1，1代表以及完成
        log.info("----->修改订单状态开始");
        orderDao.update(order.getUserId(),0);
        log.info("----->修改订单状态结束");

        log.info("----->下订单结束了，O(∩_∩)O哈哈~");
    }
}

10.OrderController

package com.atguigu.springcloud.alibaba.controller;

import com.atguigu.springcloud.alibaba.domain.CommonResult;
import com.atguigu.springcloud.alibaba.domain.Order;
import com.atguigu.springcloud.alibaba.service.OrderService;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;

/**
 * @author wsk
 * @date 2020/3/25 21:24
 */
@RestController
public class OrderController {

    @Resource
    private OrderService orderService;
    @GetMapping("/order/create")
    public CommonResult create(Order order){
        orderService.create(order);
        return new CommonResult(200,"订单创建成功");
    }
}

11,config

package com.atguigu.springcloud.alibaba.config;

import com.alibaba.druid.pool.DruidDataSource;
import io.seata.rm.datasource.DataSourceProxy;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.SqlSessionTemplate;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.core.io.support.ResourcePatternResolver;

import javax.sql.DataSource;

/**
 * @author wsk
 * @date 2020/3/25 21:26
 */
@Configuration
@MapperScan({"com.atguigu.springcloud.alibaba.dao"})
public class MyBatisConfig {
    @Value("${mybatis.mapper-locations}")
    private String mapperLocations;

    /**
     * @param sqlSessionFactory SqlSessionFactory
     * @return SqlSessionTemplate
     */
    @Bean
    public SqlSessionTemplate sqlSessionTemplate(SqlSessionFactory sqlSessionFactory) {
        return new SqlSessionTemplate(sqlSessionFactory);
    }

    /**
     * 从配置文件获取属性构造datasource，注意前缀，这里用的是druid，根据自己情况配置,
     * 原生datasource前缀取"spring.datasource"
     *
     * @return
     */
    @Bean
    @ConfigurationProperties(prefix = "spring.datasource")
    public DataSource druidDataSource() {
        return new DruidDataSource();
    }

    /**
     * 构造datasource代理对象，替换原来的datasource
     *
     * @param druidDataSource
     * @return
     */
    @Primary
    @Bean("dataSource")
    public DataSourceProxy dataSourceProxy(DataSource druidDataSource) {
        return new DataSourceProxy(druidDataSource);
    }

    @Bean(name = "sqlSessionFactory")
    public SqlSessionFactory sqlSessionFactoryBean(DataSourceProxy dataSourceProxy) throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSourceProxy);
        ResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();
        bean.setMapperLocations(resolver.getResources(mapperLocations));

        SqlSessionFactory factory;
        try {
            factory = bean.getObject();
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
        return factory;
    }
}

12.主启动类

package com.atguigu.springcloud.alibaba;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.openfeign.EnableFeignClients;

/**
 * @author wsk
 * @date 2020/3/25 20:40
 */
@EnableFeignClients
@EnableDiscoveryClient
@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)//取消数据源的自带创建
public class SeataOrderMainApp2001 {
    public static void main(String[] args) {
        SpringApplication.run(SeataOrderMainApp2001.class,args);
    }
}

库存模块 seataStorageService2002
1,pom跟之前一样
2，xml

server:
  port: 2002


spring:
  application:
    name: seata-storage-service
  cloud:
    alibaba:
      seata:
        # 自定义事务组名称需要与seata-server中的对应
        tx-service-group: fsp_tx_group
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848
  datasource:
    # 当前数据源操作类型
    type: com.alibaba.druid.pool.DruidDataSource
    # mysql驱动类
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://47.115.93.213:3306/seata_storage?useUnicode=true&characterEncoding=UTF-8&useSSL=false&serverTimezone=GMT%2B8
    username: root
    password: ljs
feign:
  hystrix:
    enabled: false
logging:
  level:
    io:
      seata: info
#ribbon的超时时间
ribbon:
  ReadTimeout: 60000
  ConnectTimeout: 60000

mybatis:
  mapper-locations: classpath*:mapper/*.xml

3，file.conf
跟上一个一样

4，registry.conf
跟上一个一样

5，domain
CommonResult跟之前一样
storage

package com.atguigu.springcloud.alibaba.domain;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
/**
 * @author wsk
 * @date 2020/3/25 21:45
 */
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Storage {
    private Long id;

    /**
     * 产品id
     */
    private Long productId;

    /**
     * 总库存
     */
    private Integer total;

    /**
     * 已用库存
     */
    private Integer used;

    /**
     * 剩余库存
     */
    private Integer residue;
}

6，dao

package com.atguigu.springcloud.alibaba.dao;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
/**
 * @author wsk
 * @date 2020/3/25 21:47
 */
@Mapper
public interface StorageDao {
    /**
     * 减库存
     * @param productId
     * @param count
     * @return
     */
    int decrease(@Param("productId") Long productId, @Param("count") Integer count);
}

7，dao.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.atguigu.springcloud.alibaba.dao.StorageDao">

    <resultMap id="BaseResultMap" type="com.atguigu.springcloud.alibaba.domain.Storage">
        <id column="id" property="id" jdbcType="BIGINT"></id>
        <result column="product_id" property="productId" jdbcType="BIGINT"></result>
        <result column="total" property="total" jdbcType="INTEGER"></result>
        <result column="used" property="used" jdbcType="INTEGER"></result>
        <result column="residue" property="residue" jdbcType="INTEGER"></result>
    </resultMap>

    <!--减库存-->
    <update id="decrease">
        update t_storage
        set used =used + #{count},residue= residue - #{count}
        where product_id=#{productId};
    </update>
</mapper>

8,service

package com.atguigu.springcloud.alibaba.service;
/**
 * @author wsk
 * @date 2020/3/25 21:51
 */
public interface StorageService {
    /**
     * 扣减库存
     * @param productId
     * @param count
     */
    void decrease(Long productId,Integer count);
}

9,serviceImpl

package com.atguigu.springcloud.alibaba.service;

import com.atguigu.springcloud.alibaba.dao.StorageDao;
import com.atguigu.springcloud.alibaba.service.StorageService;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;

@Service
public class StorageServiceImpl implements StorageService {

    @Resource
    private StorageDao storageDao;

    /**
     * 减库存
     *
     * @param productId
     * @param count
     * @return
     */
    @Override
    public void decrease(Long productId, Integer count) {
        storageDao.decrease(productId, count);
    }
}



10,controller
package com.atguigu.springcloud.alibaba.controller;
import com.atguigu.springcloud.alibaba.domain.CommonResult;
import com.atguigu.springcloud.alibaba.service.StorageService;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import javax.annotation.Resource;
/**
 * @author wsk
 * @date 2020/3/25 21:55
 */
@RestController
public class StorageController {

    @Resource
    private StorageService storageService;

    @RequestMapping("/storage/decrease")
    public CommonResult decrease(Long productId, Integer count){
        storageService.decrease(productId,count);
        return new CommonResult(200,"扣减库存成功");
    }
}

11,config
和之前一样

12，主启动类和之前一样

seata-account-service2003
1，pom一样
2。xml

server:
  port: 2003
spring:
  application:
    name: seata-account-service
  cloud:
    alibaba:
      seata:
        # 自定义事务组名称需要与seata-server中的对应
        tx-service-group: fsp_tx_group
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848
  datasource:
    # 当前数据源操作类型
    type: com.alibaba.druid.pool.DruidDataSource
    # mysql驱动类
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://47.115.93.213:3306/seata_account?useUnicode=true&characterEncoding=UTF-8&useSSL=false&serverTimezone=GMT%2B8
    username: root
    password: ljs
feign:
  hystrix:
    enabled: false
logging:
  level:
    io:
      seata: info
#ribbon的超时时间
ribbon:
  ReadTimeout: 60000
  ConnectTimeout: 60000

mybatis:
  mapper-locations: classpath*:mapper/*.xml

3，file.conf
一样
4，registry.conf
一样
5，domain
CommonResult一样
Account

package com.atguigu.springcloud.alibaba.domain;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

/**
 * 账户实体类
 *
 * @author zzyy
 * @date 2020/3/8 12:28
 **/
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Account {
    private Long id;

    /**
     * 用户id
     */
    private Long userId;

    /**
     * 总额度
     */
    private Integer total;

    /**
     * 已用额度
     */
    private Integer used;

    /**
     * 剩余额度
     */
    private Integer residue;
}

6，dao

package com.atguigu.springcloud.alibaba.dao;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import java.math.BigDecimal;
/**
 * @author wsk
 * @date 2020/3/25 22:05
 */
@Mapper
public interface AccountDao {

    /**
     * 扣减账户余额
     * @param userId
     * @param money
     */
    void decrease(@Param("userId") Long userId, @Param("money")BigDecimal money);
}

7，dao.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.atguigu.springcloud.alibaba.dao.AccountDao">

    <update id="decrease">
        update t_account set residue = residue- #{money},used = used + #{money}
        where user_id =#{userId};
    </update>
</mapper>

8，service

package com.atguigu.springcloud.alibaba.service;
import org.springframework.web.bind.annotation.RequestParam;
import java.math.BigDecimal;
/**
 * @author wsk
 * @date 2020/3/25 22:09
 */
public interface AccountService {
    /**
     * 扣减账户余额
     */
    void decrease(@RequestParam("userId") Long userId, @RequestParam("money")BigDecimal money);
}

9，serviceImpl

package com.atguigu.springcloud.alibaba.service.impl;
import com.atguigu.springcloud.alibaba.dao.AccountDao;
import com.atguigu.springcloud.alibaba.service.AccountService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import java.math.BigDecimal;
/**
 * @author wsk
 * @date 2020/3/25 22:10
 */
@Service
public class AccountServiceImpl implements AccountService {

    private static final Logger LOGGER = LoggerFactory.getLogger(AccountServiceImpl.class);

    @Resource
    AccountDao accountDao;

    @Override
    public void decrease(Long userId, BigDecimal money) {
        LOGGER.info("------>account-service中扣减账户余额开始");
        //模拟异常，全局事务回滚
       // int age=10/0;
        accountDao.decrease(userId,money);
        LOGGER.info("------>account-service中扣减账户余额结束");
    }
}

10，controller

package com.atguigu.springcloud.alibaba.controller;
import com.atguigu.springcloud.alibaba.domain.CommonResult;
import com.atguigu.springcloud.alibaba.service.AccountService;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import javax.annotation.Resource;
import java.math.BigDecimal;
/**
 * @author wsk
 * @date 2020/3/25 22:14
 */
@RestController
public class AccountController {

    @Resource
    AccountService accountService;

    @RequestMapping("/account/decrease")
    public CommonResult decrease(@RequestParam("userId") Long userId, @RequestParam("money")BigDecimal money){
        accountService.decrease(userId,money);
        return new CommonResult(200,"扣减账户余额成功");
    }
}

11，config
一样

12，主启动类
一样

然后访问localhost:2001/order/create?userId=1&productId=1&count=10&money=100

将会完成数据库操作

这时候在AccountServiceImpl里模拟异常
int age=10/0;

将会导致数据库。。。。。数据不一致的问题。。。

如何让全局事务回滚？

在事务发起者OrderServiceImpl方法前上写
@GlobalTransactional(name = “fsp-create-order”,rollbackFor = Exception.class)

                              seata原理

尽量使用1.0版本，支持集群，1.0版本支持大规模商用
TC：seata服务器
TM：事务的发起方
RM：数据库

AT模式：两阶段提交
一阶段：加载。seata拦截业务SQL在我们执行sql前seata保存到 before image
执行业务sql后保存成 after image。再加一个行锁。保证了一个阶段的原子性

二阶段：业务sql在一阶段已经提交至数据库。seata框架只需将一阶段保存的快照数据（after和before和行锁）删掉。完成数据的清除即可

二阶段回滚：
利用反向补偿机制。seata回滚。阶段已经执行的业务sql，还原业务数据。回滚则用before image还原业务数据。还原前校验脏写。对比数据库当前业务数据库和
after image的数据完全一致，则没有脏写。出现脏写。则转人工处理

本文地址：https://blog.csdn.net/ljs13168734665/article/details/107125778