公司名字大全推荐,优化方案生物,建站平台网,宁夏快速自助制作网站Spring Cloud 学习笔记#xff08;2 / 3#xff09;
Spring Cloud 学习笔记#xff08;3 / 3#xff09;
---01_前言闲聊和课程说明02_零基础微服务架构理论入门03_第二季Boot和Cloud版本选型04_Cloud组件停更说明05_父工程Project空间新建06_父工程pom文件07_复习Depend…Spring Cloud 学习笔记2 / 3
Spring Cloud 学习笔记3 / 3
---01_前言闲聊和课程说明02_零基础微服务架构理论入门03_第二季Boot和Cloud版本选型04_Cloud组件停更说明05_父工程Project空间新建06_父工程pom文件07_复习DependencyManagement和Dependencies08_支付模块构建(上)09_支付模块构建(中)10_支付模块构建(下)11_热部署Devtools12_消费者订单模块(上)13_消费者订单模块(下)14_工程重构15_Eureka基础知识16_EurekaServer服务端安装17_支付微服务8001入驻进EurekaServer18_订单微服务80入驻进EurekaServer19_Eureka集群原理说明20_Eureka集群环境构建21_订单支付两微服务注册进Eureka集群22_支付微服务集群配置23_actuator微服务信息完善24_服务发现Discovery25_Eureka自我保护理论知识26_怎么禁止自我保护27_Eureka停更说明28_支付服务注册进zookeeper29_临时还是持久节点30_订单服务注册进zookeeper31_Consul简介32_安装并运行Consul33_服务提供者注册进Consul34_服务消费者注册进Consul35_三个注册中心异同点36_Ribbon入门介绍37_Ribbon的负载均衡和Rest调用38_Ribbon默认自带的负载规则39_Ribbon负载规则替换40_Ribbon默认负载轮询算法原理41_RoundRobinRule源码分析42_Ribbon之手写轮询算法43_OpenFeign是什么44_OpenFeign服务调用45_OpenFeign超时控制46_OpenFeign日志增强47_Hystrix是什么48_Hystrix停更进维49_Hystrix的服务降级熔断限流概念初讲50_Hystrix支付微服务构建51_JMeter高并发压测后卡顿52_订单微服务调用支付服务出现卡顿53_降级容错解决的维度要求54_Hystrix之服务降级支付侧fallback55_Hystrix之服务降级订单侧fallback--
01_前言闲聊和课程说明
教学视频
源码文件1、源码文件2
02_零基础微服务架构理论入门
什么是微服务 In short, the microservice architectural style is an approach to developing a single application as a suite of small services, each running in its own process and communicating with lightweight mechanisms, often an HTTP resource API. These services are built around business capabilities and independently deployable by fully automated deployment machinery. There is a bare minimum of centralized management of these services, which may be written in different programming languages and use different data storage technologies.——James Lewis and Martin Fowler (2014) 微服务是一种架构风格一个应用拆分为一组小型服务每个服务运行在自己的进程内也就是可独立部署和升级服务之间使用轻量级HTTP交互服务围绕业务功能拆分可以由全自动部署机制独立部署去中心化服务自治。服务可以使用不同的语言、不同的存储技术
主题词01现代数字化生活-落地维度
手机PC智能家居…
主题词02分布式微服务架构-落地维度
满足哪些维度支撑起这些维度的具体技术 服务调用服务降级服务注册与发先服务熔断负载均衡服务消息队列服务网关配置中心管理自动化构建部署服务监控全链路追踪服务定时任务调度操作
Spring Cloud简介
是什么符合微服务技术维度
SpringCloud分布式微服务架构的站式解决方案是多种微服务架构落地技术的集合体俗称微服务全家桶
猜猜SpringCloud这个大集合里有多少种技术? SpringCloud俨然已成为微服务开发的主流技术栈在国内开发者社区非常火爆。
“微”力十足互联网大厂微服务架构案例
京东的 阿里的 京东物流的 Spring Cloud技术栈 总结 03_第二季Boot和Cloud版本选型 Spring Boot 2.X 版 源码地址Spring Boot 2 的新特性通过上面官网发现Boot官方强烈建议你升级到2.X以上版本 Spring Cloud H版 源码地址官网 Spring Boot 与 Spring Cloud 兼容性查看 文档JSON接口 接下来开发用到的组件版本 Cloud - Hoxton.SR1Boot - 2.2.2.RELEASECloud Alibaba - 2.1.0.RELEASEJava - Java 8Maven - 3.5及以上MySQL - 5.7及以上
04_Cloud组件停更说明 停更引发的“升级惨案” 停更不停用被动修复bugs不再接受合并请求不再发布新版本 Cloud升级 服务注册中心 × Eureka√ Zookeeper√ Consul√ Nacos 服务调用 √ Ribbon√ LoadBalancer 服务调用2 × Feign√ OpenFeign 服务降级 × Hystrix√ resilience4j√ sentienl 服务网关 × Zuul! Zuul2√ gateway 服务配置 × Config√ Nacos 服务总线 × Bus√ Nacos
Spring Cloud官方文档
Spring Cloud中文文档
Spring Boot官方文档
05_父工程Project空间新建
约定 配置 编码
创建微服务cloud整体聚合父工程Project有8个关键步骤
New Project - maven工程 - create from archetype: maven-archetype-site聚合总父工程名字Maven选版本工程名字字符编码 - Settings - File encoding注解生效激活 - Settings - Annotation ProcessorsJava编译版本选8File Type过滤 - Settings - File Type archetype 英 [ˈɑːkitaɪp] 美 [ˈɑːrkitaɪp] n. 典型 site 英 [saɪt] 美 [saɪt] n. (建筑物、城镇等的)地点位置建筑工地;现场;发生地;场所;网站;站点 v. 使坐落在;为…选址 06_父工程pom文件
?xml version1.0 encodingUTF-8?project xmlnshttp://maven.apache.org/POM/4.0.0 xmlns:xsihttp://www.w3.org/2001/XMLSchema-instancexsi:schemaLocationhttp://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsdmodelVersion4.0.0/modelVersion groupIdcom.lun/groupIdartifactIdLearnCloud/artifactIdversion1.0.0-SNAPSHOT/versionpackagingpom/packaging!-- 这里添加注意不是jar或war --!-- 统一管理jar包版本 --propertiesproject.build.sourceEncodingUTF-8/project.build.sourceEncodingmaven.compiler.source1.8/maven.compiler.sourcemaven.compiler.target1.8/maven.compiler.targetjunit.version4.12/junit.versionlog4j.version1.2.17/log4j.versionlombok.version1.16.18/lombok.versionmysql.version5.1.47/mysql.versiondruid.version1.1.16/druid.versionmybatis.spring.boot.version1.3.0/mybatis.spring.boot.version/properties!-- 子模块继承之后提供作用锁定版本子modlue不用写groupId和version --dependencyManagementdependencies!--spring boot 2.2.2--dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-dependencies/artifactIdversion2.2.2.RELEASE/versiontypepom/typescopeimport/scope/dependency!--spring cloud Hoxton.SR1--dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-dependencies/artifactIdversionHoxton.SR1/versiontypepom/typescopeimport/scope/dependency!--spring cloud alibaba 2.1.0.RELEASE--dependencygroupIdcom.alibaba.cloud/groupIdartifactIdspring-cloud-alibaba-dependencies/artifactIdversion2.1.0.RELEASE/versiontypepom/typescopeimport/scope/dependencydependencygroupIdmysql/groupIdartifactIdmysql-connector-java/artifactIdversion${mysql.version}/version/dependencydependencygroupIdcom.alibaba/groupIdartifactIddruid/artifactIdversion${druid.version}/version/dependencydependencygroupIdorg.mybatis.spring.boot/groupIdartifactIdmybatis-spring-boot-starter/artifactIdversion${mybatis.spring.boot.version}/version/dependencydependencygroupIdjunit/groupIdartifactIdjunit/artifactIdversion${junit.version}/version/dependencydependencygroupIdlog4j/groupIdartifactIdlog4j/artifactIdversion${log4j.version}/version/dependencydependencygroupIdorg.projectlombok/groupIdartifactIdlombok/artifactIdversion${lombok.version}/versionoptionaltrue/optional/dependency/dependencies/dependencyManagementbuildpluginsplugingroupIdorg.springframework.boot/groupIdartifactIdspring-boot-maven-plugin/artifactIdconfigurationforktrue/forkaddResourcestrue/addResources/configuration/plugin/plugins/build/project07_复习DependencyManagement和Dependencies
Maven使用dependencyManagement元素来提供了一种管理依赖版本号的方式。
通常会在一个组织或者项目的最顶层的父POM中看到dependencyManagement元素。
使用pom.xml中的dependencyManagement元素能让所有在子项目中引用个依赖而不用显式的列出版本量。
Maven会沿着父子层次向上走直到找到一个拥有dependencyManagement元素的项目然后它就会使用这个 dependencyManagement元素中指定的版本号。
dependencyManagementdependenciesdependencygroupIdmysq1/groupIdartifactIdmysql-connector-java/artifactIdversion5.1.2/version/dependencydependencies
/dependencyManagement然后在子项目里就可以添加mysql-connector时可以不指定版本号例如
dependenciesdependencygroupIdmysq1/groupIdartifactIdmysql-connector-java/artifactId/dependency
/dependencies这样做的好处就是如果有多个子项目都引用同一样依赖则可以避免在每个使用的子项目里都声明一个版本号这样当想升级或切换到另一个版本时只需要在顶层父容器里更新而不需要一个一个子项目的修改另外如果某个子项目需要另外的一个版本只需要声明version就可。
dependencyManagement里只是声明依赖并不实现引入因此子项目需要显示的声明需要用的依赖。如果不在子项目中声明依赖是不会从父项目中继承下来的只有在子项目中写了该依赖项,并且没有指定具体版本才会从父项目中继承该项并且version和scope都读取自父pom。如果子项目中指定了版本号那么会使用子项目中指定的jar版本。 IDEA右侧旁的Maven插件有Toggle Skip Tests Mode按钮这样maven可以跳过单元测试 父工程创建完成执行mvn : install将父工程发布到仓库方便子工程继承。
08_支付模块构建(上)
创建微服务模块套路
建Module改POM写YML主启动业务类
#mermaid-svg-ICFmCoifB3nspCLh {font-family:"trebuchet ms",verdana,arial,sans-serif;font-size:16px;fill:#333;}#mermaid-svg-ICFmCoifB3nspCLh .error-icon{fill:#552222;}#mermaid-svg-ICFmCoifB3nspCLh .error-text{fill:#552222;stroke:#552222;}#mermaid-svg-ICFmCoifB3nspCLh .edge-thickness-normal{stroke-width:2px;}#mermaid-svg-ICFmCoifB3nspCLh .edge-thickness-thick{stroke-width:3.5px;}#mermaid-svg-ICFmCoifB3nspCLh .edge-pattern-solid{stroke-dasharray:0;}#mermaid-svg-ICFmCoifB3nspCLh .edge-pattern-dashed{stroke-dasharray:3;}#mermaid-svg-ICFmCoifB3nspCLh .edge-pattern-dotted{stroke-dasharray:2;}#mermaid-svg-ICFmCoifB3nspCLh .marker{fill:#333333;stroke:#333333;}#mermaid-svg-ICFmCoifB3nspCLh .marker.cross{stroke:#333333;}#mermaid-svg-ICFmCoifB3nspCLh svg{font-family:"trebuchet ms",verdana,arial,sans-serif;font-size:16px;}#mermaid-svg-ICFmCoifB3nspCLh .label{font-family:"trebuchet ms",verdana,arial,sans-serif;color:#333;}#mermaid-svg-ICFmCoifB3nspCLh .cluster-label text{fill:#333;}#mermaid-svg-ICFmCoifB3nspCLh .cluster-label span{color:#333;}#mermaid-svg-ICFmCoifB3nspCLh .label text,#mermaid-svg-ICFmCoifB3nspCLh span{fill:#333;color:#333;}#mermaid-svg-ICFmCoifB3nspCLh .node rect,#mermaid-svg-ICFmCoifB3nspCLh .node circle,#mermaid-svg-ICFmCoifB3nspCLh .node ellipse,#mermaid-svg-ICFmCoifB3nspCLh .node polygon,#mermaid-svg-ICFmCoifB3nspCLh .node path{fill:#ECECFF;stroke:#9370DB;stroke-width:1px;}#mermaid-svg-ICFmCoifB3nspCLh .node .label{text-align:center;}#mermaid-svg-ICFmCoifB3nspCLh .node.clickable{cursor:pointer;}#mermaid-svg-ICFmCoifB3nspCLh .arrowheadPath{fill:#333333;}#mermaid-svg-ICFmCoifB3nspCLh .edgePath .path{stroke:#333333;stroke-width:2.0px;}#mermaid-svg-ICFmCoifB3nspCLh .flowchart-link{stroke:#333333;fill:none;}#mermaid-svg-ICFmCoifB3nspCLh .edgeLabel{background-color:#e8e8e8;text-align:center;}#mermaid-svg-ICFmCoifB3nspCLh .edgeLabel rect{opacity:0.5;background-color:#e8e8e8;fill:#e8e8e8;}#mermaid-svg-ICFmCoifB3nspCLh .cluster rect{fill:#ffffde;stroke:#aaaa33;stroke-width:1px;}#mermaid-svg-ICFmCoifB3nspCLh .cluster text{fill:#333;}#mermaid-svg-ICFmCoifB3nspCLh .cluster span{color:#333;}#mermaid-svg-ICFmCoifB3nspCLh div.mermaidTooltip{position:absolute;text-align:center;max-width:200px;padding:2px;font-family:"trebuchet ms",verdana,arial,sans-serif;font-size:12px;background:hsl(80, 100%, 96.2745098039%);border:1px solid #aaaa33;border-radius:2px;pointer-events:none;z-index:100;}#mermaid-svg-ICFmCoifB3nspCLh :root{--mermaid-font-family:"trebuchet ms",verdana,arial,sans-serif;}客户端消费者80order微服务提供者8001payment创建cloud-provider-payment8001微服务提供者支付Module模块
1.建名为cloud-provider-payment8001的Maven工程
2.改POM
?xml version1.0 encodingUTF-8?
project xmlnshttp://maven.apache.org/POM/4.0.0xmlns:xsihttp://www.w3.org/2001/XMLSchema-instancexsi:schemaLocationhttp://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsdparentartifactIdLearnCloud/artifactIdgroupIdcom.lun/groupIdversion1.0.0-SNAPSHOT/version/parentmodelVersion4.0.0/modelVersionartifactIdcloud-provider-payment8001/artifactIddependencies!--包含了sleuthzipkin--dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-zipkin/artifactId/dependency!--eureka-client--dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-netflix-eureka-client/artifactId/dependency!-- 引入自己定义的api通用包可以使用Payment支付Entity --!--dependencygroupIdcom.atguigu.springcloud/groupIdartifactIdcloud-api-commons/artifactIdversion${project.version}/version/dependency--dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-web/artifactId/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-actuator/artifactId/dependencydependencygroupIdorg.mybatis.spring.boot/groupIdartifactIdmybatis-spring-boot-starter/artifactId/dependencydependencygroupIdcom.alibaba/groupIdartifactIddruid-spring-boot-starter/artifactIdversion1.1.10/version/dependency!--mysql-connector-java--dependencygroupIdmysql/groupIdartifactIdmysql-connector-java/artifactId/dependency!--jdbc--dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-jdbc/artifactId/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-devtools/artifactIdscoperuntime/scopeoptionaltrue/optional/dependencydependencygroupIdorg.projectlombok/groupIdartifactIdlombok/artifactIdoptionaltrue/optional/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-test/artifactIdscopetest/scope/dependency/dependencies/project3.写YML
server:port: 8001spring:application:name: cloud-payment-servicedatasource:type: com.alibaba.druid.pool.DruidDataSource # 当前数据源操作类型driver-class-name: org.gjt.mm.mysql.Driver # mysql驱动包url: jdbc:mysql://localhost:3306/my?useUnicodetruecharacterEncodingutf-8useSSLfalseusername: rootpassword: 1234mybatis:mapperLocations: classpath:mapper/*.xmltype-aliases-package: com.lun.springcloud.entities # 所有Entity别名类所在包
4.主启动
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;SpringBootApplication
public class PaymentMain001 {public static void main(String[] args) {SpringApplication.run(PaymentMain001.class, args);}
}09_支付模块构建(中)
5.业务类
SQL
CREATE TABLE payment(id bigint(20) NOT NULL AUTO_INCREMENT COMMENT ID,serial varchar(200) DEFAULT ,PRIMARY KEY (id)
)ENGINEInnoDB AUTO_INCREMENT1 DEFAULT CHARSETutf8mb4Entities
实体类Payment
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;import java.io.Serializable;Data
AllArgsConstructor
NoArgsConstructor
public class Payment implements Serializable {private Long id;private String serial;
}JSON封装体CommonResult
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;Data
AllArgsConstructor
NoArgsConstructor
public class CommonResultT{private Integer code;private String message;private T data;public CommonResult(Integer code, String message){this(code, message, null);}
}DAO
接口PaymentDao
import com.atguigu.springcloud.entities.Payment;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;/***/
Mapper
//Repository不用Spring的
public interface PaymentDao
{public int create(Payment payment);public Payment getPaymentById(Param(id) Long id);
}MyBatis映射文件PaymentMapper.xml路径resources/mapper/PaymentMapper.xml
?xml version1.0 encodingUTF-8 ?
!DOCTYPE mapper PUBLIC -//mybatis.org//DTD Mapper 3.0//EN http://mybatis.org/dtd/mybatis-3-mapper.dtd mapper namespacecom.lun.springcloud.dao.PaymentDaoinsert idcreate parameterTypePayment useGeneratedKeystrue keyPropertyidinsert into payment(serial) values(#{serial});/insertresultMap idBaseResultMap typecom.lun.springcloud.entities.Paymentid columnid propertyid jdbcTypeBIGINT/id columnserial propertyserial jdbcTypeVARCHAR//resultMapselect idgetPaymentById parameterTypeLong resultMapBaseResultMapselect * from payment where id#{id};/select/mapperService
接口PaymentService
import com.lun.springcloud.entities.Payment;
import org.apache.ibatis.annotations.Param;/***/
public interface PaymentService
{public int create(Payment payment);public Payment getPaymentById(Param(id) Long id);
}
实现类
import com.lun.springcloud.dao.PaymentDao;
import com.lun.springcloud.entities.Payment;
import com.lun.springcloud.service.PaymentService;
import org.apache.ibatis.annotations.Param;
import org.springframework.stereotype.Service;import javax.annotation.Resource;/***/
Service
public class PaymentServiceImpl implements PaymentService
{Resourceprivate PaymentDao paymentDao;public int create(Payment payment){return paymentDao.create(payment);}public Payment getPaymentById(Long id){return paymentDao.getPaymentById(id);}
}Controller
import com.lun.springcloud.entities.CommonResult;
import com.lun.springcloud.entities.Payment;
import com.lun.springcloud.service.PaymentService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.web.bind.annotation.*;
import org.springframework.cloud.client.discovery.DiscoveryClient;import javax.annotation.Resource;
import java.util.List;
import java.util.concurrent.TimeUnit;/***/
RestController
Slf4j
public class PaymentController{Resourceprivate PaymentService paymentService;PostMapping(value /payment/create)public CommonResult create(Payment payment){int result paymentService.create(payment);log.info(*****插入结果result);if(result 0){return new CommonResult(200,插入数据库成功,serverPort: serverPort,result);}else{return new CommonResult(444,插入数据库失败,null);}}GetMapping(value /payment/get/{id})public CommonResultPayment getPaymentById(PathVariable(id) Long id){Payment payment paymentService.getPaymentById(id);if(payment ! null){return new CommonResult(200,查询成功,serverPort: serverPort,payment);}else{return new CommonResult(444,没有对应记录,查询ID: id,null);}}
}10_支付模块构建(下)
6.测试
浏览器 - http://localhost:8001/payment/get/1Postman - http://localhost:8001/payment/create?seriallun2
7.小总结
创建微服务模块套路
建Module改POM写YML主启动业务类
11_热部署Devtools
开发时使用生产环境关闭
1.Adding devtools to your project
dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-devtools/artifactIdscoperuntime/scopeoptionaltrue/optional
/dependency2.Adding plugin to your pom.xml
下段配置复制到聚合父类总工程的pom.xml
build!--finalName你的工程名/finalName单一工程时添加--pluginsplugingroupIdorg.springframework.boot/groupIdartifactIdspring-boot-maven-plugin/artifactIdconfigurationforktrue/forkaddResourcestrue/addResources/configuration/plugin/plugins
/build3.Enabling automatic build
File - Settings(New Project Settings-Settings for New Projects) -Complier
下面项勾选
Automatically show first error in editorDisplay notification on build completionBuild project automaticallyCompile independent modules in parallel
4.Update the value of
键入Ctrl Shift Alt / 打开Registry勾选 compiler.automake.allow.when.app.running actionSystem.assertFocusAccessFromEdt
5.重启IDEA
12_消费者订单模块(上)
1.建Module
创建名为cloud-consumer-order80的maven工程。
2.改POM
?xml version1.0 encodingUTF-8?project xmlnshttp://maven.apache.org/POM/4.0.0 xmlns:xsihttp://www.w3.org/2001/XMLSchema-instancexsi:schemaLocationhttp://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsdparentartifactIdLearnCloud/artifactIdgroupIdcom.lun/groupIdversion1.0.0-SNAPSHOT/version/parentmodelVersion4.0.0/modelVersionartifactIdcloud-consumer-order80/artifactIdpropertiesproject.build.sourceEncodingUTF-8/project.build.sourceEncodingmaven.compiler.source1.7/maven.compiler.sourcemaven.compiler.target1.7/maven.compiler.target/propertiesdependenciesdependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-web/artifactId/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-actuator/artifactId/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-devtools/artifactIdscoperuntime/scopeoptionaltrue/optional/dependencydependencygroupIdorg.projectlombok/groupIdartifactIdlombok/artifactIdoptionaltrue/optional/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-test/artifactIdscopetest/scope/dependency/dependencies
/project
3.写YML
server:port: 804.主启动
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;/*** Hello world!**/
SpringBootApplication
public class OrderMain80
{public static void main( String[] args ){SpringApplication.run(OrderMain80.class, args);}
}5.业务类
实体类
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;import java.io.Serializable;Data
AllArgsConstructor
NoArgsConstructor
public class Payment implements Serializable {private Long id;private String serial;
}import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;Data
AllArgsConstructor
NoArgsConstructor
public class CommonResultT{private Integer code;private String message;private T data;public CommonResult(Integer code, String message){this(code, message, null);}
}控制层
import com.lun.springcloud.entities.CommonResult;
import com.lun.springcloud.entities.Payment;
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.RestController;
import org.springframework.web.client.RestTemplate;import javax.annotation.Resource;Slf4j
RestController
public class OrderController {public static final String PAYMENT_URL http://localhost:8001;Resourceprivate RestTemplate restTemplate;GetMapping(/consumer/payment/create)public CommonResultPayment create(Payment payment){return restTemplate.postForObject(PAYMENT_URL/payment/create, payment, CommonResult.class);}GetMapping(/consumer/payment/get/{id})public CommonResultPayment getPayment(PathVariable(id) Long id){return restTemplate.getForObject(PAYMENT_URL/payment/get/id, CommonResult.class);}
}配置类
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.client.RestTemplate;Configuration
public class ApplicationContextConfig {Beanpublic RestTemplate getRestTemplate(){return new RestTemplate();}}6.测试
运行cloud-consumer-order80与cloud-provider-payment8001两工程
浏览器 - http://localhost/consumer/payment/get/1
RestTemplate
RestTemplate提供了多种便捷访问远程Http服务的方法是一种简单便捷的访问restful服务模板类是Spring提供的用于访问Rest服务的客户端模板工具集
官网地址
使用
使用restTemplate访问restful接口非常的简单粗暴无脑。(url, requestMap, ResponseBean.class)这三个参数分别代表。REST请求地址、请求参数、HTTP响应转换被转换成的对象类型。
13_消费者订单模块(下)
浏览器 - http://localhost/consumer/payment/create?seriallun3
虽然返回成功但是观测数据库中并没有创建serial为lun3的行。
解决之道在loud-provider-payment8001工程的PaymentController中添加RequestBody注解。
public class PaymentController
{PostMapping(value /payment/create)public CommonResult create(RequestBody/*添加到这里*/ Payment payment){...}
}通过修改idea的workspace.xml的方式来快速打开Run Dashboard窗口这个用来显示哪些Spring Boot工程运行停止等信息。我idea 2020.1版本在名为Services窗口就可以显示哪些Spring Boot工程运行停止等信息出来所以这仅作记录参考。 开启Run DashBoard 打开工程路径下的.idea文件夹的workspace.xml 在component nameRunDashboard中修改或添加以下代码
option nameconfigurationTypessetoption valueSpringBootApplicationConfigurationType//set
/option由于idea版本差异可能需要关闭重启。
14_工程重构
观察cloud-consumer-order80与cloud-provider-payment8001两工程有重复代码entities包下的实体坏味道重构。
1.新建 - cloud-api-commons
2.POM
?xml version1.0 encodingUTF-8?
project xmlnshttp://maven.apache.org/POM/4.0.0xmlns:xsihttp://www.w3.org/2001/XMLSchema-instancexsi:schemaLocationhttp://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsdparentartifactIdLearnCloud/artifactIdgroupIdcom.lun.springcloud/groupIdversion1.0.0-SNAPSHOT/version/parentmodelVersion4.0.0/modelVersionartifactIdcloud-api-commons/artifactIddependenciesdependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-devtools/artifactIdscoperuntime/scopeoptionaltrue/optional/dependencydependencygroupIdorg.projectlombok/groupIdartifactIdlombok/artifactIdoptionaltrue/optional/dependencydependencygroupIdcn.hutool/groupIdartifactIdhutool-all/artifactIdversion5.1.0/version/dependency/dependencies/project3.entities
将cloud-consumer-order80与cloud-provider-payment8001两工程的公有entities包移至cloud-api-commons工程下。
4.maven clean、install cloud-api-commons工程以供给cloud-consumer-order80与cloud-provider-payment8001两工程调用。
5.订单80和支付8001分别改造
将cloud-consumer-order80与cloud-provider-payment8001两工程的公有entities包移除引入cloud-api-commons依赖
dependencygroupIdcom.lun.springcloud/groupIdartifactIdcloud-api-commons/artifactIdversion${project.version}/version
/dependency6.测试
15_Eureka基础知识
什么是服务治理
Spring Cloud封装了Netflix 公司开发的Eureka模块来实现服务治理
在传统的RPC远程调用框架中管理每个服务与服务之间依赖关系比较复杂管理比较复杂所以需要使用服务治理管理服务于服务之间依赖关系可以实现服务调用、负载均衡、容错等实现服务发现与注册。
什么是服务注册与发现
Eureka采用了CS的设计架构Eureka Sever作为服务注册功能的服务器它是服务注册中心。而系统中的其他微服务使用Eureka的客户端连接到 Eureka Server并维持心跳连接。这样系统的维护人员就可以通过Eureka Server来监控系统中各个微服务是否正常运行。
在服务注册与发现中有一个注册中心。当服务器启动的时候会把当前自己服务器的信息比如服务地址通讯地址等以别名方式注册到注册中心上。另一方(消费者服务提供者)以该别名的方式去注册中心上获取到实际的服务通讯地址然后再实现本地RPC调用RPC远程调用框架核心设计思想:在于注册中心因为使用注册中心管理每个服务与服务之间的一个依赖关系(服务治理概念)。在任何RPC远程框架中都会有一个注册中心存放服务地址相关信息(接口地址) Eureka包含两个组件:Eureka Server和Eureka Client
Eureka Server提供服务注册服务
各个微服务节点通过配置启动后会在EurekaServer中进行注册这样EurekaServer中的服务注册表中将会存储所有可用服务节点的信息服务节点的信息可以在界面中直观看到。
EurekaClient通过注册中心进行访问
它是一个Java客户端用于简化Eureka Server的交互客户端同时也具备一个内置的、使用轮询(round-robin)负载算法的负载均衡器。在应用启动后将会向Eureka Server发送心跳(默认周期为30秒)。如果Eureka Server在多个心跳周期内没有接收到某个节点的心跳EurekaServer将会从服务注册表中把这个服务节点移除默认90秒)
16_EurekaServer服务端安装
IDEA生成eurekaServer端服务注册中心类似物业公司
1.创建名为cloud-eureka-server7001的Maven工程
2.修改pom.xml
!-- eureka新旧版本 --
!-- 以前的老版本2018--
dependencygroupidorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-eureka/artifactId
/dependency!-- 现在新版本2020.2--!-- 我们使用最新的 --
dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-netflix-eureka-server/artifactId
/dependency?xml version1.0 encodingUTF-8?
project xmlnshttp://maven.apache.org/POM/4.0.0xmlns:xsihttp://www.w3.org/2001/XMLSchema-instancexsi:schemaLocationhttp://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsdparentartifactIdLearnCloud/artifactIdgroupIdcom.lun.springcloud/groupIdversion1.0.0-SNAPSHOT/version/parentmodelVersion4.0.0/modelVersionartifactIdcloud-eureka-server7001/artifactIddependencies!--eureka-server--dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-netflix-eureka-server/artifactId/dependency!-- 引入自己定义的api通用包可以使用Payment支付Entity --dependencygroupIdcom.lun.springcloud/groupIdartifactIdcloud-api-commons/artifactIdversion${project.version}/version/dependency!--boot web actuator--dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-web/artifactId/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-actuator/artifactId/dependency!--一般通用配置--dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-devtools/artifactIdscoperuntime/scopeoptionaltrue/optional/dependencydependencygroupIdorg.projectlombok/groupIdartifactIdlombok/artifactId/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-test/artifactIdscopetest/scope/dependencydependencygroupIdjunit/groupIdartifactIdjunit/artifactId/dependency/dependencies/project3.添加application.yml
server:port: 7001eureka:instance:hostname: locathost #eureka服务端的实例名称client:#false表示不向注册中心注册自己。register-with-eureka: false#false表示自己端就是注册中心我的职责就是维护服务实例并不需要去检索服务fetch-registry: falseservice-url:#设置与Eureka server交互的地址查询服务和注册服务都需要依赖这个地址。defaultZone: http://${eureka.instance.hostname}:${server.port}/eureka/4.主启动
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;SpringBootApplication
EnableEurekaServer
public class EurekaMain7001 {public static void main(String[] args) {SpringApplication.run(EurekaMain7001.class, args);}
}
5.测试运行EurekaMain7001浏览器输入http://localhost:7001/回车会查看到Spring Eureka服务主页。
17_支付微服务8001入驻进EurekaServer
EurekaClient端cloud-provider-payment8001将注册进EurekaServer成为服务提供者provider类似学校对外提供授课服务。
1.修改cloud-provider-payment8001
2.改POM
添加spring-cloud-starter-netflix-eureka-client依赖
dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-netflix-eureka-client/artifactId
/dependency3.写YML
eureka:client:#表示是否将自己注册进Eurekaserver默认为true。register-with-eureka: true#是否从EurekaServer抓取已有的注册信息默认为true。单节点无所谓集群必须设置为true才能配合ribbon使用负载均衡fetchRegistry: trueservice-url:defaultZone: http://localhost:7001/eureka4.主启动
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;SpringBootApplication
EnableEurekaClient//-----添加该注解
public class PaymentMain001 {public static void main(String[] args) {SpringApplication.run(PaymentMain001.class, args);}
}5.测试 启动cloud-provider-payment8001和cloud-eureka-server7001工程。 浏览器输入 - http://localhost:7001/ 主页内的Instances currently registered with Eureka会显示cloud-provider-payment8001的配置文件application.yml设置的应用名cloud-payment-service
spring:application:name: cloud-payment-service6.自我保护机制
EMERGENCY! EUREKA MAY BE INCORRECTLY CLAIMING INSTANCES ARE UP WHEN THEY’RE NOT. RENEWALS ARELESSER THAN THRESHOLD AND HENCFT ARE NOT BEING EXPIRED JUST TO BE SAFE.
紧急情况EUREKA可能错误地声称实例在没有启动的情况下启动了。续订小于阈值因此实例不会为了安全而过期。
18_订单微服务80入驻进EurekaServer
EurekaClient端cloud-consumer-order80将注册进EurekaServer成为服务消费者consumer类似来上课消费的同学
1.cloud-consumer-order80
2.POM
dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-netflix-eureka-client/artifactId
/dependency3.YML
server:port: 80spring:application:name: cloud-order-serviceeureka:client:#表示是否将自己注册进Eurekaserver默认为true。register-with-eureka: true#是否从EurekaServer抓取已有的注册信息默认为true。单节点无所谓集群必须设置为true才能配合ribbon使用负载均衡fetchRegistry: trueservice-url:defaultZone: http://localhost:7001/eureka4.主启动
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;SpringBootApplication
EnableEurekaClient//--- 添加该标签
public class OrderMain80
{public static void main( String[] args ){SpringApplication.run(OrderMain80.class, args);}
}5.测试
启动cloud-provider-payment8001、cloud-eureka-server7001和cloud-consumer-order80这三工程。浏览器输入 http://localhost:7001 , 在主页的Instances currently registered with Eureka将会看到cloud-provider-payment8001、cloud-consumer-order80两个工程名。 注意application.yml配置中层次缩进和空格两者不能少否则会抛出异常Failed to bind properties under eureka.client.service-url to java.util.Map java.lang.String, java.lang.String。
19_Eureka集群原理说明
1.Eureka集群原理说明 服务注册将服务信息注册进注册中心
服务发现从注册中心上获取服务信息
实质存key服务命取value闭用地址
1先启动eureka注主册中心
2启动服务提供者payment支付服务
3支付服务启动后会把自身信息(比服务地址L以别名方式注朋进eureka
4消费者order服务在需要调用接口时使用服务别名去注册中心获取实际的RPC远程调用地址
5消去者导调用地址后底屋实际是利用HttpClient技术实现远程调用
6消费者实癸导服务地址后会缓存在本地jvm内存中默认每间隔30秒更新—次服务调用地址
问题:微服务RPC远程服务调用最核心的是什么 高可用试想你的注册中心只有一个only one万一它出故障了会导致整个为服务环境不可用。
解决办法搭建Eureka注册中心集群实现负载均衡故障容错。
互相注册相互守望。
20_Eureka集群环境构建
创建cloud-eureka-server7002工程过程参考16_EurekaServer服务端安装
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127.0.0.1 eureka7001.com
127.0.0.1 eureka7002.com修改cloud-eureka-server7001配置文件
server:port: 7001eureka:instance:hostname: eureka7001.com #eureka服务端的实例名称client:register-with-eureka: false #false表示不向注册中心注册自己。fetch-registry: false #false表示自己端就是注册中心我的职责就是维护服务实例并不需要去检索服务service-url:#集群指向其它eurekadefaultZone: http://eureka7002.com:7002/eureka/#单机就是7001自己#defaultZone: http://eureka7001.com:7001/eureka/修改cloud-eureka-server7002配置文件
server:port: 7002eureka:instance:hostname: eureka7002.com #eureka服务端的实例名称client:register-with-eureka: false #false表示不向注册中心注册自己。fetch-registry: false #false表示自己端就是注册中心我的职责就是维护服务实例并不需要去检索服务service-url:#集群指向其它eurekadefaultZone: http://eureka7001.com:7001/eureka/#单机就是7002自己#defaultZone: http://eureka7002.com:7002/eureka/实践的时候遇到异常情况
在开启cloud-eureka-server7002时开启失败说7002端口被占用然后在cmd中输入netstat -ano | find 7002查不到任何东西。
纳闷一阵重启电脑问题解决。
21_订单支付两微服务注册进Eureka集群
将支付服务8001微服务订单服务80微服务发布到上面2台Eureka集群配置中
将它们的配置文件的eureka.client.service-url.defaultZone进行修改
eureka:client:#表示是否将自己注册进Eurekaserver默认为true。register-with-eureka: true#是否从EurekaServer抓取已有的注册信息默认为true。单节点无所谓集群必须设置为true才能配合ribbon使用负载均衡fetchRegistry: trueservice-url:defaultZone: http://eureka7001.com:7001/eureka, http://eureka7002.com:7002/eureka测试01 先要启动EurekaServer7001/7002服务再要启动服务提供者provider8001再要启动消费者80浏览器输入 - http://localhost/consumer/payment/get/1
22_支付微服务集群配置
支付服务提供者8001集群环境构建
参考cloud-provicer-payment8001
1.新建cloud-provider-payment8002
2.改POM
3.写YML - 端口8002
4.主启动
5.业务类
6.修改8001/8002的Controller添加serverPort
RestController
Slf4j
public class PaymentController{Value(${server.port})private String serverPort;//添加serverPortPostMapping(value /payment/create)public CommonResult create(RequestBody Payment payment){int result paymentService.create(payment);log.info(*****插入结果 result);if(result 0) {return new CommonResult(200,插入数据库成功,serverPort: serverPort/*添加到此处*/, result);}else{return new CommonResult(444,插入数据库失败,null);}}
}负载均衡
cloud-consumer-order80订单服务访问地址不能写死
Slf4j
RestController
public class OrderController {//public static final String PAYMENT_URL http://localhost:8001;public static final String PAYMENT_URL http://CLOUD-PAYMENT-SERVICE;...
}使用LoadBalanced注解赋予RestTemplate负载均衡的能力
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
public class ApplicationContextConfig {BeanLoadBalanced//使用LoadBalanced注解赋予RestTemplate负载均衡的能力public RestTemplate getRestTemplate(){return new RestTemplate();}}ApplicationContextBean - 提前说一下Ribbon的负载均衡功能
测试
先要启动EurekaServer7001/7002服务
再要启动服务提供者provider8001/8002服务
浏览器输入 - http://localhost/consumer/payment/get/31
结果负载均衡效果达到8001/8002端口交替出现
Ribbon和Eureka整合后Consumer可以直接调用服务而不用再关心地址和端口号且该服务还有负载功能。
相互注册相互守望 23_actuator微服务信息完善
主机名称服务名称修改也就是将IP地址换成可读性高的名字
修改cloud-provider-payment8001cloud-provider-payment8002
修改部分 - YML - eureka.instance.instance-id
eureka:...instance:instance-id: payment8001 #添加此处eureka:...instance:instance-id: payment8002 #添加此处修改之后
eureka主页将显示payment8001payment8002代替原来显示的IP地址。 访问信息有IP信息提示就是将鼠标指针移至payment8001payment8002名下会有IP地址提示
修改部分 - YML - eureka.instance.prefer-ip-address
eureka:...instance:instance-id: payment8001 prefer-ip-address: true #添加此处eureka:...instance:instance-id: payment8002prefer-ip-address: true #添加此处24_服务发现Discovery
对于注册进eureka里面的微服务可以通过服务发现来获得该服务的信息
修改cloud-provider-payment8001的Controller
RestController
Slf4j
public class PaymentController{...Resourceprivate DiscoveryClient discoveryClient;...GetMapping(value /payment/discovery)public Object discovery(){ListString services discoveryClient.getServices();for (String element : services) {log.info(*****element: element);}ListServiceInstance instances discoveryClient.getInstances(CLOUD-PAYMENT-SERVICE);for (ServiceInstance instance : instances) {log.info(instance.getServiceId()\tinstance.getHost()\tinstance.getPort()\tinstance.getUri());}return this.discoveryClient;}
}8001主启动类
SpringBootApplication
EnableEurekaClient
EnableDiscoveryClient//添加该注解
public class PaymentMain001 {public static void main(String[] args) {SpringApplication.run(PaymentMain001.class, args);}
}
自测
先要启动EurekaSeryer
再启动8001主启动类需要稍等一会儿
浏览器输入http://localhost:8001/payment/discovery
浏览器输出
{services:[cloud-payment-service],order:0}后台输出
*****element: cloud-payment-service
CLOUD-PAYMENT-SERVICE 192.168.199.218 8001 http://192.168.199.218:800125_Eureka自我保护理论知识
概述
保护模式主要用于一组客户端和Eureka Server之间存在网络分区场景下的保护。一旦进入保护模式Eureka Server将会尝试保护其服务注册表中的信息不再删除服务注册表中的数据也就是不会注销任何微服务。
如果在Eureka Server的首页看到以下这段提示则说明Eureka进入了保护模式:
EMERGENCY! EUREKA MAY BE INCORRECTLY CLAIMING INSTANCES ARE UP WHEN THEY’RE NOT. RENEWALS ARE LESSER THANTHRESHOLD AND HENCE THE INSTANCES ARE NOT BEING EXPIRED JUSTTO BE SAFE
导致原因
一句话某时刻某一个微服务不可用了Eureka不会立刻清理依旧会对该微服务的信息进行保存。
属于CAP里面的AP分支。
为什么会产生Eureka自我保护机制?
为了EurekaClient可以正常运行防止与EurekaServer网络不通情况下EurekaServer不会立刻将EurekaClient服务剔除
什么是自我保护模式?
默认情况下如果EurekaServer在一定时间内没有接收到某个微服务实例的心跳EurekaServer将会注销该实例(默认90秒)。但是当网络分区故障发生(延时、卡顿、拥挤)时微服务与EurekaServer之间无法正常通信以上行为可能变得非常危险了——因为微服务本身其实是健康的此时本不应该注销这个微服务。Eureka通过“自我保护模式”来解决这个问题——当EurekaServer节点在短时间内丢失过多客户端时(可能发生了网络分区故障)那么这个节点就会进入自我保护模式。 自我保护机制∶默认情况下EurekaClient定时向EurekaServer端发送心跳包
如果Eureka在server端在一定时间内(默认90秒)没有收到EurekaClient发送心跳包便会直接从服务注册列表中剔除该服务但是在短时间( 90秒中)内丢失了大量的服务实例心跳这时候Eurekaserver会开启自我保护机制不会剔除该服务该现象可能出现在如果网络不通但是EurekaClient为出现宕机此时如果换做别的注册中心如果一定时间内没有收到心跳会将剔除该服务这样就出现了严重失误因为客户端还能正常发送心跳只是网络延迟问题而保护机制是为了解决此问题而产生的)。
在自我保护模式中Eureka Server会保护服务注册表中的信息不再注销任何服务实例。
它的设计哲学就是宁可保留错误的服务注册信息也不盲目注销任何可能健康的服务实例。一句话讲解好死不如赖活着。
综上自我保护模式是一种应对网络异常的安全保护措施。它的架构哲学是宁可同时保留所有微服务健康的微服务和不健康的微服务都会保留也不盲目注销任何健康的微服务。使用自我保护模式可以让Eureka集群更加的健壮、稳定。
26_怎么禁止自我保护
在eurekaServer端7001处设置关闭自我保护机制
出厂默认自我保护机制是开启的
使用eureka.server.enable-self-preservation false可以禁用自我保护模式
eureka:...server:#关闭自我保护机制保证不可用服务被及时踢除enable-self-preservation: falseeviction-interval-timer-in-ms: 2000关闭效果
spring-eureka主页会显示出一句
THE SELF PRESERVATION MODE IS TURNED OFF. THIS MAY NOT PROTECT INSTANCE EXPIRY IN CASE OF NETWORK/OTHER PROBLEMS. 生产者客户端eureakeClient端8001
默认
eureka.instance.lease-renewal-interval-in-seconds30
eureka.instance.lease-expiration-duration-in-seconds90
eureka:...instance:instance-id: payment8001prefer-ip-address: true#心跳检测与续约时间#开发时没置小些保证服务关闭后注册中心能即使剔除服务#Eureka客户端向服务端发送心跳的时间间隔单位为秒(默认是30秒)lease-renewal-interval-in-seconds: 1#Eureka服务端在收到最后一次心跳后等待时间上限单位为秒(默认是90秒)超时将剔除服务lease-expiration-duration-in-seconds: 2测试 7001和8001都配置完成先启动7001再启动8001
结果先关闭8001马上被删除了
27_Eureka停更说明
https://github.com/Netflix/eureka/wiki Eureka 2.0 (Discontinued) The existing open source work on eureka 2.0 is discontinued. The code base and artifacts that were released as part of the existing repository of work on the 2.x branch is considered use at your own risk. Eureka 1.x is a core part of Netflix’s service discovery system and is still an active project. 我们用ZooKeeper代替Eureka功能。
28_支付服务注册进zookeeper
注册中心Zookeeper
zookeeper是一个分布式协调工具可以实现注册中心功能
关闭Linux服务器防火墙后启动zookeeper服务器
用到的Linux命令行
systemctl stop firewalld关闭防火墙systemctl status firewalld查看防火墙状态ipconfig查看IP地址ping查验结果
zookeeper服务器取代Eureka服务器zk作为服务注册中心 视频里是用虚拟机CentOS开启ZooKeeper我打算在本机启动ZooKeeper具体操作参考ZooKeeper学习笔记。
服务提供者
1.新建名为cloud-provider-payment8004的Maven工程。
2.POM
?xml version1.0 encodingUTF-8?
project xmlnshttp://maven.apache.org/POM/4.0.0xmlns:xsihttp://www.w3.org/2001/XMLSchema-instancexsi:schemaLocationhttp://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsdparentartifactIdLearnCloud/artifactIdgroupIdcom.lun.springcloud/groupIdversion1.0.0-SNAPSHOT/version/parentmodelVersion4.0.0/modelVersionartifactIdcloud-provider-payment8004/artifactIddependencies!-- SpringBoot整合Web组件 --dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-web/artifactId/dependencydependency!-- 引入自己定义的api通用包可以使用Payment支付Entity --groupIdcom.lun.springcloud/groupIdartifactIdcloud-api-commons/artifactIdversion${project.version}/version/dependency!-- SpringBoot整合zookeeper客户端 --dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-zookeeper-discovery/artifactId!--先排除自带的zookeeper3.5.3 防止与3.4.9起冲突--exclusionsexclusiongroupIdorg.apache.zookeeper/groupIdartifactIdzookeeper/artifactId/exclusion/exclusions/dependency!--添加zookeeper3.4.9版本--dependencygroupIdorg.apache.zookeeper/groupIdartifactIdzookeeper/artifactIdversion3.4.9/version/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-devtools/artifactIdscoperuntime/scopeoptionaltrue/optional/dependencydependencygroupIdorg.projectlombok/groupIdartifactIdlombok/artifactIdoptionaltrue/optional/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-test/artifactIdscopetest/scope/dependency/dependencies/project3.YML
#8004表示注册到zookeeper服务器的支付服务提供者端口号
server:port: 8004#服务别名----注册zookeeper到注册中心名称
spring:application:name: cloud-provider-paymentcloud:zookeeper:connect-string: 127.0.0.1:2181 # 192.168.111.144:2181 #4.主启动类
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;SpringBootApplication
EnableDiscoveryClient//该注解用于向使用consul或者zookeeper作为注册中心时注册服务
public class PaymentMain8004 {public static void main(String[] args) {SpringApplication.run(PaymentMain8004.class, args);}
}5.Controller
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;import java.util.UUID;RestController
Slf4j
public class PaymentController
{Value(${server.port})private String serverPort;RequestMapping(value /payment/zk)public String paymentzk(){return springcloud with zookeeper: serverPort\t UUID.randomUUID().toString();}
}
6.启动8004注册进zookeeper要先启动zookeeper的server 验证测试浏览器 - http://localhost:8004/payment/zk 验证测试2 接着用zookeeper客户端操作
[zk: localhost:2181(CONNECTED) 0] ls /
[services, zookeeper]
[zk: localhost:2181(CONNECTED) 1] ls /services/cloud-provider-payment
[a4567f50-6ad9-47a3-9fbb-7391f41a9f3d]
[zk: localhost:2181(CONNECTED) 2] get /services/cloud-provider-payment/a4567f50-6ad9-47a3-9fbb-7391f41a9f3d
{name:cloud-provider-payment,id:a4567f50-6ad9-47a3-9fbb-7391f41a9f3d,address:192.168.199.218,port:8004,ss
lPort:null,payload:{class:org.springframework.cloud.zookeeper.discovery.ZookeeperInstance,id:application-1,
name:cloud-provider-payment,metadata:{}},registrationTimeUTC:1612811116918,serviceType:DYNAMIC,uriSpec:{pa
rts:[{value:scheme,variable:true},{value:://,variable:false},{value:address,variable:true},{value:
:,variable:false},{value:port,variable:true}]}}
[zk: localhost:2181(CONNECTED) 3]json格式化get /services/cloud-provider-payment/a4567f50-6ad9-47a3-9fbb-7391f41a9f3d的结果
{name: cloud-provider-payment, id: a4567f50-6ad9-47a3-9fbb-7391f41a9f3d, address: 192.168.199.218, port: 8004, sslPort: null, payload: {class: org.springframework.cloud.zookeeper.discovery.ZookeeperInstance, id: application-1, name: cloud-provider-payment, metadata: { }}, registrationTimeUTC: 1612811116918, serviceType: DYNAMIC, uriSpec: {parts: [{value: scheme, variable: true}, {value: ://, variable: false}, {value: address, variable: true}, {value: :, variable: false}, {value: port, variable: true}]}
}29_临时还是持久节点
ZooKeeper的服务节点是临时节点没有Eureka那含情脉脉。
30_订单服务注册进zookeeper
1.新建cloud-consumerzk-order80
2.POM
?xml version1.0 encodingUTF-8?
project xmlnshttp://maven.apache.org/POM/4.0.0xmlns:xsihttp://www.w3.org/2001/XMLSchema-instancexsi:schemaLocationhttp://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsdparentartifactIdLearnCloud/artifactIdgroupIdcom.lun.springcloud/groupIdversion1.0.0-SNAPSHOT/version/parentmodelVersion4.0.0/modelVersionartifactIdcloud-consumerzk-order80/artifactIddependencies!-- SpringBoot整合Web组件 --dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-web/artifactId/dependency!-- SpringBoot整合zookeeper客户端 --dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-zookeeper-discovery/artifactId!--先排除自带的zookeeper--exclusionsexclusiongroupIdorg.apache.zookeeper/groupIdartifactIdzookeeper/artifactId/exclusion/exclusions/dependency!--添加zookeeper3.4.9版本--dependencygroupIdorg.apache.zookeeper/groupIdartifactIdzookeeper/artifactIdversion3.4.9/version/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-devtools/artifactIdscoperuntime/scopeoptionaltrue/optional/dependencydependencygroupIdorg.projectlombok/groupIdartifactIdlombok/artifactIdoptionaltrue/optional/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-test/artifactIdscopetest/scope/dependency/dependencies/project3.YML
server:port: 80#服务别名----注册zookeeper到注册中心名称
spring:application:name: cloud-consumer-ordercloud:zookeeper:connect-string: 127.0.0.1:2181 # 192.168.111.144:2181 #4.主启动
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;SpringBootApplication
EnableDiscoveryClient
public class OrderZKMain80 {public static void main(String[] args) {SpringApplication.run(OrderZKMain80.class, args);}
}5.业务类
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
public class ApplicationContextConfig
{BeanLoadBalancedpublic RestTemplate getRestTemplate(){return new RestTemplate();}
}import javax.annotation.Resource;RestController
Slf4j
public class OrderZKController
{public static final String INVOKE_URL http://cloud-provider-payment;Resourceprivate RestTemplate restTemplate;GetMapping(value /consumer/payment/zk)public String paymentInfo(){String result restTemplate.getForObject(INVOKE_URL/payment/zk,String.class);return result;}
}6.验证测试
运行ZooKeeper服务端cloud-consumerzk-order80cloud-provider-payment8004。
打开ZooKeeper客户端
[zk: localhost:2181(CONNECTED) 0] ls /
[services, zookeeper]
[zk: localhost:2181(CONNECTED) 1] ls /services
[cloud-consumer-order, cloud-provider-payment]
[zk: localhost:2181(CONNECTED) 2]7.访问测试地址 - http://localhost/consumer/payment/zk
31_Consul简介
Consul官网
Consul下载地址 What is Consul? Consul is a service mesh solution providing a full featured control plane with service discovery, configuration, and segmentation functionality. Each of these features can be used individually as needed, or they can be used together to build a full service mesh. Consul requires a data plane and supports both a proxy and native integration model. Consul ships with a simple built-in proxy so that everything works out of the box, but also supports 3rd party proxy integrations such as Envoy. link Consul是一个服务网格解决方案它提供了一个功能齐全的控制平面具有服务发现、配置和分段功能。这些特性中的每一个都可以根据需要单独使用也可以一起用于构建全服务网格。Consul需要一个数据平面并支持代理和本机集成模型。Consul船与一个简单的内置代理使一切工作的开箱即用但也支持第三方代理集成如Envoy。 consul 英 [ˈkɒnsl] 美 [ˈkɑːnsl] n. 领事 Consul是一套开源的分布式服务发现和配置管理系统由HashiCorp 公司用Go语言开发。
提供了微服务系统中的服务治理、配置中心、控制总线等功能。这些功能中的每一个都可以根据需要单独使用也可以一起使用以构建全方位的服务网格总之Consul提供了一种完整的服务网格解决方案。
它具有很多优点。包括基于raft协议比较简洁支持健康检查同时支持HTTP和DNS协议支持跨数据中心的WAN集群提供图形界面跨平台支持Linux、Mac、Windows。 The key features of Consul are: Service Discovery: Clients of Consul can register a service, such as api or mysql, and other clients can use Consul to discover providers of a given service. Using either DNS or HTTP, applications can easily find the services they depend upon.Health Checking: Consul clients can provide any number of health checks, either associated with a given service (“is the webserver returning 200 OK”), or with the local node (“is memory utilization below 90%”). This information can be used by an operator to monitor cluster health, and it is used by the service discovery components to route traffic away from unhealthy hosts.KV Store: Applications can make use of Consul’s hierarchical key/value store for any number of purposes, including dynamic configuration, feature flagging, coordination, leader election, and more. The simple HTTP API makes it easy to use.Secure Service Communication: Consul can generate and distribute TLS certificates for services to establish mutual TLS connections. Intentions can be used to define which services are allowed to communicate. Service segmentation can be easily managed with intentions that can be changed in real time instead of using complex network topologies and static firewall rules.Multi Datacenter: Consul supports multiple datacenters out of the box. This means users of Consul do not have to worry about building additional layers of abstraction to grow to multiple regions. link 能干嘛
服务发现 - 提供HTTP和DNS两种发现方式。健康监测 - 支持多种方式HTTP、TCP、Docker、Shell脚本定制化KV存储 - Key、Value的存储方式多数据中心 - Consul支持多数据中心可视化Web界面
怎么玩
32_安装并运行Consul
官网安装说明
windows版解压缩后得consul.exe打开cmd
查看版本consul -v
D:\Consulconsul -v
Consul v1.9.3
Revision f55da9306
Protocol 2 spoken by default, understands 2 to 3 (agent will automatically use protocol 2 when speaking to compatible agents)开发模式启动consul agent -dev
浏览器输入 - http://localhost:8500/ - 打开Consul控制页。
33_服务提供者注册进Consul
1.新建Module支付服务provider8006
2.POM
?xml version1.0 encodingUTF-8?
project xmlnshttp://maven.apache.org/POM/4.0.0xmlns:xsihttp://www.w3.org/2001/XMLSchema-instancexsi:schemaLocationhttp://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsdparentartifactIdLearnCloud/artifactIdgroupIdcom.lun.springcloud/groupIdversion1.0.0-SNAPSHOT/version/parentmodelVersion4.0.0/modelVersionartifactIdcloud-providerconsul-payment8006/artifactIddependencies!-- 引入自己定义的api通用包可以使用Payment支付Entity --dependencygroupIdcom.lun.springcloud/groupIdartifactIdcloud-api-commons/artifactIdversion${project.version}/version/dependency!--SpringCloud consul-server --dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-consul-discovery/artifactId/dependency!-- SpringBoot整合Web组件 --dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-web/artifactId/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-actuator/artifactId/dependency!--日常通用jar包配置--dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-devtools/artifactIdscoperuntime/scopeoptionaltrue/optional/dependencydependencygroupIdorg.projectlombok/groupIdartifactIdlombok/artifactIdoptionaltrue/optional/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-test/artifactIdscopetest/scope/dependencydependencygroupIdcn.hutool/groupIdartifactIdhutool-all/artifactIdversionRELEASE/versionscopetest/scope/dependencydependencygroupIdcn.hutool/groupIdartifactIdhutool-all/artifactIdversionRELEASE/versionscopetest/scope/dependency/dependencies/project3.YML
###consul服务端口号
server:port: 8006spring:application:name: consul-provider-payment
####consul注册中心地址cloud:consul:host: localhostport: 8500discovery:#hostname: 127.0.0.1service-name: ${spring.application.name}4.主启动类
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;SpringBootApplication
EnableDiscoveryClient
public class PaymentMain8006
{public static void main(String[] args) {SpringApplication.run(PaymentMain8006.class, args);}
}5.业务类Controller
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;import java.util.UUID;RestController
Slf4j
public class PaymentController
{Value(${server.port})private String serverPort;RequestMapping(value /payment/consul)public String paymentConsul(){return springcloud with consul: serverPort\t UUID.randomUUID().toString();}
}
6.验证测试
http://localhost:8006/payment/consulhttp://localhost:8500 - 会显示provider8006
34_服务消费者注册进Consul
1.新建Module消费服务order80 - cloud-consumerconsul-order80
2.POM
?xml version1.0 encodingUTF-8?
project xmlnshttp://maven.apache.org/POM/4.0.0xmlns:xsihttp://www.w3.org/2001/XMLSchema-instancexsi:schemaLocationhttp://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsdparentartifactIdLearnCloud/artifactIdgroupIdcom.lun.springcloud/groupIdversion1.0.0-SNAPSHOT/version/parentmodelVersion4.0.0/modelVersionartifactIdcloud-consumerconsul-order80/artifactIddependencies!--SpringCloud consul-server --dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-consul-discovery/artifactId/dependency!-- SpringBoot整合Web组件 --dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-web/artifactId/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-actuator/artifactId/dependency!--日常通用jar包配置--dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-devtools/artifactIdscoperuntime/scopeoptionaltrue/optional/dependencydependencygroupIdorg.projectlombok/groupIdartifactIdlombok/artifactIdoptionaltrue/optional/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-test/artifactIdscopetest/scope/dependency/dependencies
/project3.YML
###consul服务端口号
server:port: 80spring:application:name: cloud-consumer-order
####consul注册中心地址cloud:consul:host: localhostport: 8500discovery:#hostname: 127.0.0.1service-name: ${spring.application.name}4.主启动类
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;SpringBootApplication
EnableDiscoveryClient //该注解用于向使用consul或者zookeeper作为注册中心时注册服务
public class OrderConsulMain80
{public static void main(String[] args) {SpringApplication.run(OrderConsulMain80.class, args);}
}
5.配置Bean
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
public class ApplicationContextConfig
{BeanLoadBalancedpublic RestTemplate getRestTemplate(){return new RestTemplate();}
}6.Controller
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;import javax.annotation.Resource;RestController
Slf4j
public class OrderConsulController
{public static final String INVOKE_URL http://consul-provider-payment;Resourceprivate RestTemplate restTemplate;GetMapping(value /consumer/payment/consul)public String paymentInfo(){String result restTemplate.getForObject(INVOKE_URL/payment/consul,String.class);return result;}
}7.验证测试
运行consulcloud-providerconsul-payment8006cloud-consumerconsul-order80
http://localhost:8500/ 主页会显示出consulcloud-providerconsul-payment8006cloud-consumerconsul-order80三服务。
8.访问测试地址 - http://localhost/consumer/payment/consul
35_三个注册中心异同点
组件名语言CAP服务健康检查对外暴露接口Spring Cloud集成EurekaJavaAP可配支持HTTPConsulGoCP支持HTTP/DNSZookeeperJavaCP支持客户端已集成
CAP CConsistency (强一致性) AAvailability (可用性) PPartition tolerance 分区容错性) 最多只能同时较好的满足两个。
CAP理论的核心是一个分布式系统不可能同时很好的满足一致性可用性和分区容错性这三个需求。
因此根据CAP原理将NoSQL数据库分成了满足CA原则、满足CP原则和满足AP原则三大类:
CA - 单点集群满足—致性可用性的系统通常在可扩展性上不太强大。CP - 满足一致性分区容忍必的系统通常性能不是特别高。AP - 满足可用性分区容忍性的系统通常可能对一致性要求低一些。 AP架构Eureka
当网络分区出现后为了保证可用性系统B可以返回旧值保证系统的可用性。
结论违背了一致性C的要求只满足可用性和分区容错即AP CP架构ZooKeeper/Consul
当网络分区出现后为了保证一致性就必须拒接请求否则无法保证一致性。
结论违背了可用性A的要求只满足一致性和分区容错即CP。 CP 与 AP 对立同一的矛盾关系。
36_Ribbon入门介绍
Spring Cloud Ribbon是基于Netflix Ribbon实现的一套客户端负载均衡的工具。
简单的说Ribbon是Netflix发布的开源项目主要功能是提供客户端的软件负载均衡算法和服务调用。Ribbon客户端组件提供一系列完善的配置项如连接超时重试等。
简单的说就是在配置文件中列出Load Balancer(简称LB)后面所有的机器Ribbon会自动的帮助你基于某种规则(如简单轮询随机连接等去连接这些机器。我们很容易使用Ribbon实现自定义的负载均衡算法。 ribbon 英 [ˈrɪbən] 美 [ˈrɪbən] n. (用于捆绑或装饰的)带子;丝带;带状物;狭长的东西;绶带;勋带 Github - Ribbon
Ribbon目前也进入维护模式。
Ribbon未来可能被Spring Cloud LoadBalacer替代。
LB负载均衡(Load Balance)是什么
简单的说就是将用户的请求平摊的分配到多个服务上从而达到系统的HA (高可用)。
常见的负载均衡有软件NginxLVS硬件F5等。
Ribbon本地负载均衡客户端VS Nginx服务端负载均衡区别
Nginx是服务器负载均衡客户端所有请求都会交给nginx然后由nginx实现转发请求。即负载均衡是由服务端实现的。 Ribbon本地负载均衡在调用微服务接口时候会在注册中心上获取注册信息服务列表之后缓存到JVM本地从而在本地实现RPC远程服务调用技术。
集中式LB
即在服务的消费方和提供方之间使用独立的LB设施(可以是硬件如F5, 也可以是软件如nginx)由该设施负责把访问请求通过某种策略转发至服务的提供方;
进程内LB
将LB逻辑集成到消费方消费方从服务注册中心获知有哪些地址可用然后自己再从这些地址中选择出一个合适的服务器。
Ribbon就属于进程内LB它只是一个类库集成于消费方进程消费方通过它来获取到服务提供方的地址。
一句话
负载均衡 RestTemplate调用
37_Ribbon的负载均衡和Rest调用
架构说明
总结Ribbon其实就是一个软负载均衡的客户端组件它可以和其他所需请求的客户端结合使用和Eureka结合只是其中的一个实例。 Ribbon在工作时分成两步 第一步先选择EurekaServer ,它优先选择在同一个区域内负载较少的server。 第二步再根据用户指定的策略在从server取到的服务注册列表中选择一个地址。
其中Ribbon提供了多种策略比如轮询、随机和根据响应时间加权。
POM
先前工程项目没有引入spring-cloud-starter-ribbon也可以使用ribbon。
dependencygroupldorg.springframework.cloud/groupldartifactldspring-cloud-starter-netflix-ribbon/artifactid
/dependency这是因为spring-cloud-starter-netflix-eureka-client自带了spring-cloud-starter-ribbon引用。
二说RestTemplate的使用
RestTemplate Java Doc
getForObject() / getForEntity() - GET请求方法
getForObject()返回对象为响应体中数据转化成的对象基本上可以理解为Json。
getForEntity()返回对象为ResponseEntity对象包含了响应中的一些重要信息比如响应头、响应状态码、响应体等。
GetMapping(/consumer/payment/getForEntity/{id})
public CommonResultPayment getPayment2(PathVariable(id) Long id)
{ResponseEntityCommonResult entity restTemplate.getForEntity(PAYMENT_URL/payment/get/id,CommonResult.class);if(entity.getStatusCode().is2xxSuccessful()){return entity.getBody();//getForObject()}else{return new CommonResult(444,操作失败);}
}postForObject() / postForEntity() - POST请求方法
38_Ribbon默认自带的负载规则
lRule根据特定算法中从服务列表中选取一个要访问的服务 RoundRobinRule 轮询RandomRule 随机RetryRule 先按照RoundRobinRule的策略获取服务如果获取服务失败则在指定时间内会进行重WeightedResponseTimeRule 对RoundRobinRule的扩展响应速度越快的实例选择权重越大越容易被选择BestAvailableRule 会先过滤掉由于多次访问故障而处于断路器跳闸状态的服务然后选择一个并发量最小的服务AvailabilityFilteringRule 先过滤掉故障实例再选择并发较小的实例ZoneAvoidanceRule 默认规则,复合判断server所在区域的性能和server的可用性选择服务器
39_Ribbon负载规则替换
1.修改cloud-consumer-order80
2.注意配置细节
官方文档明确给出了警告:
这个自定义配置类不能放在ComponentScan所扫描的当前包下以及子包下
否则我们自定义的这个配置类就会被所有的Ribbon客户端所共享达不到特殊化定制的目的了。
也就是说不要将Ribbon配置类与主启动类同包
3.新建package - com.lun.myrule
4.在com.lun.myrule下新建MySelfRule规则类
import com.netflix.loadbalancer.IRule;
import com.netflix.loadbalancer.RandomRule;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;Configuration
public class MySelfRule {Beanpublic IRule myRule(){return new RandomRule();}
}5.主启动类添加RibbonClient
import com.lun.myrule.MySelfRule;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.cloud.netflix.ribbon.RibbonClient;SpringBootApplication
EnableEurekaClient
//添加到此处
RibbonClient(name CLOUD-PAYMENT-SERVICE, configuration MySelfRule.class)
public class OrderMain80
{public static void main( String[] args ){SpringApplication.run(OrderMain80.class, args);}
}6.测试
开启cloud-eureka-server7001cloud-consumer-order80cloud-provider-payment8001cloud-provider-payment8002
浏览器-输入http://localhost/consumer/payment/get/1
返回结果中的serverPort在8001与8002两种间反复横跳。
40_Ribbon默认负载轮询算法原理
默认负载轮训算法: rest接口第几次请求数 % 服务器集群总数量 实际调用服务器位置下标每次服务重启动后rest接口计数从1开始。
ListServicelnstance instances discoveryClient.getInstances(CLOUD-PAYMENT-SERVICE);
如:
List [0] instances 127.0.0.1:8002List [1] instances 127.0.0.1:8001
8001 8002组合成为集群它们共计2台机器集群总数为2按照轮询算法原理
当总请求数为1时:1%21对应下标位置为1则获得服务地址为127.0.0.1:8001当总请求数位2时:2%2О对应下标位置为0则获得服务地址为127.0.0.1:8002当总请求数位3时:3%21对应下标位置为1则获得服务地址为127.0.0.1:8001当总请求数位4时:4%2О对应下标位置为0则获得服务地址为127.0.0.1:8002如此类推…
41_RoundRobinRule源码分析
public interface IRule{/** choose one alive server from lb.allServers or* lb.upServers according to key* * return choosen Server object. NULL is returned if none* server is available *///重点关注这方法public Server choose(Object key);public void setLoadBalancer(ILoadBalancer lb);public ILoadBalancer getLoadBalancer();
}package com.netflix.loadbalancer;import com.netflix.client.config.IClientConfig;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;/*** The most well known and basic load balancing strategy, i.e. Round Robin Rule.** author stonse* author Nikos Michalakis nikosnetflix.com**/
public class RoundRobinRule extends AbstractLoadBalancerRule {private AtomicInteger nextServerCyclicCounter;private static final boolean AVAILABLE_ONLY_SERVERS true;private static final boolean ALL_SERVERS false;private static Logger log LoggerFactory.getLogger(RoundRobinRule.class);public RoundRobinRule() {nextServerCyclicCounter new AtomicInteger(0);}public RoundRobinRule(ILoadBalancer lb) {this();setLoadBalancer(lb);}//重点关注这方法。public Server choose(ILoadBalancer lb, Object key) {if (lb null) {log.warn(no load balancer);return null;}Server server null;int count 0;while (server null count 10) {ListServer reachableServers lb.getReachableServers();ListServer allServers lb.getAllServers();int upCount reachableServers.size();int serverCount allServers.size();if ((upCount 0) || (serverCount 0)) {log.warn(No up servers available from load balancer: lb);return null;}int nextServerIndex incrementAndGetModulo(serverCount);server allServers.get(nextServerIndex);if (server null) {/* Transient. */Thread.yield();continue;}if (server.isAlive() (server.isReadyToServe())) {return (server);}// Next.server null;}if (count 10) {log.warn(No available alive servers after 10 tries from load balancer: lb);}return server;}/*** Inspired by the implementation of {link AtomicInteger#incrementAndGet()}.** param modulo The modulo to bound the value of the counter.* return The next value.*/private int incrementAndGetModulo(int modulo) {for (;;) {int current nextServerCyclicCounter.get();int next (current 1) % modulo;//求余法if (nextServerCyclicCounter.compareAndSet(current, next))return next;}}Overridepublic Server choose(Object key) {return choose(getLoadBalancer(), key);}Overridepublic void initWithNiwsConfig(IClientConfig clientConfig) {}
}42_Ribbon之手写轮询算法
自己试着写一个类似RoundRobinRule的本地负载均衡器。 7001/7002集群启动 8001/8002微服务改造- controller
RestController
Slf4j
public class PaymentController{...GetMapping(value /payment/lb)public String getPaymentLB() {return serverPort;//返回服务接口}...
}80订单微服务改造
1.ApplicationContextConfig去掉注解LoadBalancedOrderMain80去掉注解RibbonClient
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
public class ApplicationContextConfig {Bean//LoadBalancedpublic RestTemplate getRestTemplate(){return new RestTemplate();}}2.创建LoadBalancer接口
import org.springframework.cloud.client.ServiceInstance;import java.util.List;/***/
public interface LoadBalancer
{ServiceInstance instances(ListServiceInstance serviceInstances);
}3.MyLB
实现LoadBalancer接口
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.stereotype.Component;import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;/***/
Component//需要跟主启动类同包或者在其子孙包下。
public class MyLB implements LoadBalancer
{private AtomicInteger atomicInteger new AtomicInteger(0);public final int getAndIncrement(){int current;int next;do {current this.atomicInteger.get();next current 2147483647 ? 0 : current 1;}while(!this.atomicInteger.compareAndSet(current,next));System.out.println(*****第几次访问次数next: next);return next;}//负载均衡算法rest接口第几次请求数 % 服务器集群总数量 实际调用服务器位置下标 每次服务重启动后rest接口计数从1开始。Overridepublic ServiceInstance instances(ListServiceInstance serviceInstances){int index getAndIncrement() % serviceInstances.size();return serviceInstances.get(index);}
}
4.OrderController
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import com.lun.springcloud.lb.LoadBalancer;Slf4j
RestController
public class OrderController {//public static final String PAYMENT_URL http://localhost:8001;public static final String PAYMENT_URL http://CLOUD-PAYMENT-SERVICE;...Resourceprivate LoadBalancer loadBalancer;Resourceprivate DiscoveryClient discoveryClient;...GetMapping(value /consumer/payment/lb)public String getPaymentLB(){ListServiceInstance instances discoveryClient.getInstances(CLOUD-PAYMENT-SERVICE);if(instances null || instances.size() 0){return null;}ServiceInstance serviceInstance loadBalancer.instances(instances);URI uri serviceInstance.getUri();return restTemplate.getForObject(uri/payment/lb,String.class);}
}5.测试 不停地刷新http://localhost/consumer/payment/lb可以看到8001/8002交替出现。
43_OpenFeign是什么
官方文档
Github地址 Feign is a declarative web service client. It makes writing web service clients easier. To use Feign create an interface and annotate it. It has pluggable annotation support including Feign annotations and JAX-RS annotations. Feign also supports pluggable encoders and decoders. Spring Cloud adds support for Spring MVC annotations and for using the same HttpMessageConverters used by default in Spring Web. Spring Cloud integrates Ribbon and Eureka, as well as Spring Cloud LoadBalancer to provide a load-balanced http client when using Feign. link Feign是一个声明式WebService客户端。使用Feign能让编写Web Service客户端更加简单。它的使用方法是定义一个服务接口然后在上面添加注解。Feign也支持可拔插式的编码器和解码器。Spring Cloud对Feign进行了封装使其支持了Spring MVC标准注解和HttpMessageConverters。Feign可以与Eureka和Ribbon组合使用以支持负载均衡。 Feign能干什么
Feign旨在使编写Java Http客户端变得更容易。
前面在使用RibbonRestTemplate时利用RestTemplate对http请求的封装处理形成了一套模版化的调用方法。但是在实际开发中由于对服务依赖的调用可能不止一处往往一个接口会被多处调用所以通常都会针对每个微服务自行封装一些客户端类来包装这些依赖服务的调用。所以Feign在此基础上做了进一步封装由他来帮助我们定义和实现依赖服务接口的定义。在Feign的实现下我们只需创建一个接口并使用注解的方式来配置它(以前是Dao接口上面标注Mapper注解,现在是一个微服务接口上面标注一个Feign注解即可)即可完成对服务提供方的接口绑定简化了使用Spring cloud Ribbon时自动封装服务调用客户端的开发量。
Feign集成了Ribbon
利用Ribbon维护了Payment的服务列表信息并且通过轮询实现了客户端的负载均衡。而与Ribbon不同的是通过feign只需要定义服务绑定接口且以声明式的方法优雅而简单的实现了服务调用。
Feign和OpenFeign两者区别
Feign是Spring Cloud组件中的一个轻量级RESTful的HTTP服务客户端Feign内置了Ribbon用来做客户端负载均衡去调用服务注册中心的服务。Feign的使用方式是:使用Feign的注解定义接口调用这个接口就可以调用服务注册中心的服务。
dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-feign/artifactId
/dependencyOpenFeign是Spring Cloud在Feign的基础上支持了SpringMVC的注解如RequesMapping等等。OpenFeign的Feignclient可以解析SpringMVc的RequestMapping注解下的接口并通过动态代理的方式产生实现类实现类中做负载均衡并调用其他服务。
dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-openfeign/artifactId
/dependencyfeign 英 [feɪn] 美 [feɪn] v. 假装装作佯装(有某种感觉或生病、疲倦等) 44_OpenFeign服务调用
接口注解微服务调用接口 FeignClient
1.新建cloud-consumer-feign-order80
2.POM
?xml version1.0 encodingUTF-8?
project xmlnshttp://maven.apache.org/POM/4.0.0xmlns:xsihttp://www.w3.org/2001/XMLSchema-instancexsi:schemaLocationhttp://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsdparentartifactIdLearnCloud/artifactIdgroupIdcom.lun.springcloud/groupIdversion1.0.0-SNAPSHOT/version/parentmodelVersion4.0.0/modelVersionartifactIdcloud-consumer-feign-order80/artifactIddependencies!--openfeign--dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-openfeign/artifactId/dependency!--eureka client--dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-netflix-eureka-client/artifactId/dependency!-- 引入自己定义的api通用包可以使用Payment支付Entity --dependencygroupIdcom.lun.springcloud/groupIdartifactIdcloud-api-commons/artifactIdversion${project.version}/version/dependency!--web--dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-web/artifactId/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-actuator/artifactId/dependency!--一般基础通用配置--dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-devtools/artifactIdscoperuntime/scopeoptionaltrue/optional/dependencydependencygroupIdorg.projectlombok/groupIdartifactIdlombok/artifactIdoptionaltrue/optional/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-test/artifactIdscopetest/scope/dependency/dependencies/project3.YML
server:port: 80eureka:client:register-with-eureka: falseservice-url:defaultZone: http://eureka7001.com:7001/eureka/,http://eureka7002.com:7002/eureka/4.主启动
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.openfeign.EnableFeignClients;SpringBootApplication
EnableFeignClients
public class OrderFeignMain80 {public static void main(String[] args) {SpringApplication.run(OrderFeignMain80.class, args);}
}
5.业务类
业务逻辑接口FeignClient配置调用provider服务
新建PaymentFeignService接口并新增注解FeignClient
import com.lun.springcloud.entities.CommonResult;
import com.lun.springcloud.entities.Payment;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.stereotype.Component;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;Component
FeignClient(value CLOUD-PAYMENT-SERVICE)
public interface PaymentFeignService
{GetMapping(value /payment/get/{id})public CommonResultPayment getPaymentById(PathVariable(id) Long id);}控制层Controller
import com.lun.springcloud.entities.CommonResult;
import com.lun.springcloud.entities.Payment;
import com.lun.springcloud.service.PaymentFeignService;
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.RestController;
import javax.annotation.Resource;RestController
Slf4j
public class OrderFeignController
{Resourceprivate PaymentFeignService paymentFeignService;GetMapping(value /consumer/payment/get/{id})public CommonResultPayment getPaymentById(PathVariable(id) Long id){return paymentFeignService.getPaymentById(id);}}
6.测试
先启动2个eureka集群7001/7002
再启动2个微服务8001/8002
启动OpenFeign启动
http://localhost/consumer/payment/get/1
Feign自带负载均衡配置项
45_OpenFeign超时控制
超时设置故意设置超时演示出错情况
1.服务提供方8001/8002故意写暂停程序
RestController
Slf4j
public class PaymentController {...Value(${server.port})private String serverPort;...GetMapping(value /payment/feign/timeout)public String paymentFeignTimeout(){// 业务逻辑处理正确但是需要耗费3秒钟try {TimeUnit.SECONDS.sleep(3);} catch (InterruptedException e) {e.printStackTrace();}return serverPort;}...
}2.服务消费方80添加超时方法PaymentFeignService
Component
FeignClient(value CLOUD-PAYMENT-SERVICE)
public interface PaymentFeignService{...GetMapping(value /payment/feign/timeout)public String paymentFeignTimeout();
}
3.服务消费方80添加超时方法OrderFeignController
RestController
Slf4j
public class OrderFeignController
{Resourceprivate PaymentFeignService paymentFeignService;...GetMapping(value /consumer/payment/feign/timeout)public String paymentFeignTimeout(){// OpenFeign客户端一般默认等待1秒钟return paymentFeignService.paymentFeignTimeout();}
}4.测试
多次刷新http://localhost/consumer/payment/feign/timeout
将会跳出错误Spring Boot默认错误页面主要异常feign.RetryableException:Read timed out executing GET http://CLOUD-PAYMENT-SERVCE/payment/feign/timeout。
OpenFeign默认等待1秒钟超过后报错
YML文件里需要开启OpenFeign客户端超时控制
#设置feign客户端超时时间(OpenFeign默认支持ribbon)(单位毫秒)
ribbon:#指的是建立连接所用的时间适用于网络状况正常的情况下,两端连接所用的时间ReadTimeout: 5000#指的是建立连接后从服务器读取到可用资源所用的时间ConnectTimeout: 500046_OpenFeign日志增强
日志打印功能
Feign提供了日志打印功能我们可以通过配置来调整日恙级别从而了解Feign 中 Http请求的细节。
说白了就是对Feign接口的调用情况进行监控和输出
日志级别
NONE默认的不显示任何日志;BASIC仅记录请求方法、URL、响应状态码及执行时间;HEADERS除了BASIC中定义的信息之外还有请求和响应的头信息;FULL除了HEADERS中定义的信息之外还有请求和响应的正文及元数据。
配置日志bean
import feign.Logger;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;Configuration
public class FeignConfig
{BeanLogger.Level feignLoggerLevel(){return Logger.Level.FULL;}
}
YML文件里需要开启日志的Feign客户端
logging:level:# feign日志以什么级别监控哪个接口com.lun.springcloud.service.PaymentFeignService: debug后台日志查看
得到更多日志信息。
47_Hystrix是什么
概述
分布式系统面临的问题
复杂分布式体系结构中的应用程序有数十个依赖关系每个依赖关系在某些时候将不可避免地失败。
服务雪崩
多个微服务之间调用的时候假设微服务A调用微服务B和微服务C微服务B和微服务C又调用其它的微服务这就是所谓的“扇出”。如果扇出的链路上某个微服务的调用响应时间过长或者不可用对微服务A的调用就会占用越来越多的系统资源进而引起系统崩溃所谓的“雪崩效应”. 对于高流量的应用来说单一的后避依赖可能会导致所有服务器上的所有资源都在几秒钟内饱和。比失败更糟糕的是这些应用程序还可能导致服务之间的延迟增加备份队列线程和其他系统资源紧张导致整个系统发生更多的级联故障。这些都表示需要对故障和延迟进行隔离和管理以便单个依赖关系的失败不能取消整个应用程序或系统。
所以通常当你发现一个模块下的某个实例失败后这时候这个模块依然还会接收流量然后这个有问题的模块还调用了其他的模块这样就会发生级联故障或者叫雪崩。
Hystrix是什么
Hystrix是一个用于处理分布式系统的延迟和容错的开源库在分布式系统里许多依赖不可避免的会调用失败比如超时、异常等Hystrix能够保证在一个依赖出问题的情况下不会导致整体服务失败避免级联故障以提高分布式系统的弹性。
断路器”本身是一种开关装置当某个服务单元发生故障之后通过断路器的故障监控类似熔断保险丝)向调用方返回一个符合预期的、可处理的备选响应FallBack)而不是长时间的等待或者抛出调用方无法处理的异常这样就保证了服务调用方的线程不会被长时间、不必要地占用从而避免了故障在分布式系统中的蔓延乃至雪崩。 hystrix n. 豪猪属;猬草属;豪猪;豪猪亚属 48_Hystrix停更进维
能干嘛
服务降级服务熔断接近实对的监控…
官网资料
link
Hystrix官宣停更进维
link
被动修bugs不再接受合并请求不再发布新版本
49_Hystrix的服务降级熔断限流概念初讲
服务降级
服务器忙请稍后再试不让客户端等待并立刻返回一个友好提示fallback
哪些情况会出发降级
程序运行导常超时服务熔断触发服务降级线程池/信号量打满也会导致服务降级
服务熔断
类比保险丝达到最大服务访问后直接拒绝访问拉闸限电然后调用服务降级的方法并返回友好提示。
服务的降级 - 进而熔断 - 恢复调用链路
服务限流
秒杀高并发等操作严禁一窝蜂的过来拥挤大家排队一秒钟N个有序进行。
50_Hystrix支付微服务构建
将cloud-eureka-server7001改配置成单机版
1.新建cloud-provider-hygtrix-payment8001
2.POM
?xml version1.0 encodingUTF-8?
project xmlnshttp://maven.apache.org/POM/4.0.0xmlns:xsihttp://www.w3.org/2001/XMLSchema-instancexsi:schemaLocationhttp://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsdparentartifactIdcloud2020/artifactIdgroupIdcom.atguigu.springcloud/groupIdversion1.0-SNAPSHOT/version/parentmodelVersion4.0.0/modelVersionartifactIdcloud-provider-hystrix-payment8001/artifactIddependencies!--hystrix--dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-netflix-hystrix/artifactId/dependency!--eureka client--dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-netflix-eureka-client/artifactId/dependency!--web--dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-web/artifactId/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-actuator/artifactId/dependencydependency!-- 引入自己定义的api通用包可以使用Payment支付Entity --groupIdcom.atguigu.springcloud/groupIdartifactIdcloud-api-commons/artifactIdversion${project.version}/version/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-devtools/artifactIdscoperuntime/scopeoptionaltrue/optional/dependencydependencygroupIdorg.projectlombok/groupIdartifactIdlombok/artifactIdoptionaltrue/optional/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-test/artifactIdscopetest/scope/dependency/dependencies/project3.YML
server:port: 8001spring:application:name: cloud-provider-hystrix-paymenteureka:client:register-with-eureka: truefetch-registry: trueservice-url:#defaultZone: http://eureka7001.com:7001/eureka,http://eureka7002.com:7002/eurekadefaultZone: http://eureka7001.com:7001/eureka4.主启动
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;/***/
SpringBootApplication
EnableEurekaClient
public class PaymentHystrixMain8001
{public static void main(String[] args) {SpringApplication.run(PaymentHystrixMain8001.class, args);}
}5.业务类
service
import org.springframework.stereotype.Service;import java.util.concurrent.TimeUnit;/***/
Service
public class PaymentService {/***/public String paymentInfo_OK(Integer id){return 线程池: Thread.currentThread().getName() paymentInfo_OK,id: id\tO(∩_∩)O哈哈~;}public String paymentInfo_TimeOut(Integer id){try { TimeUnit.MILLISECONDS.sleep(3000); } catch (InterruptedException e) { e.printStackTrace(); }return 线程池: Thread.currentThread().getName() id: id\tO(∩_∩)O哈哈~ 耗时(秒): 3;}
}controller
import com.lun.springcloud.service.PaymentService;
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.PathVariable;
import org.springframework.web.bind.annotation.RestController;import javax.annotation.Resource;/***/
RestController
Slf4j
public class PaymentController
{Resourceprivate PaymentService paymentService;Value(${server.port})private String serverPort;GetMapping(/payment/hystrix/ok/{id})public String paymentInfo_OK(PathVariable(id) Integer id){String result paymentService.paymentInfo_OK(id);log.info(*****result: result);return result;}GetMapping(/payment/hystrix/timeout/{id})public String paymentInfo_TimeOut(PathVariable(id) Integer id){String result paymentService.paymentInfo_TimeOut(id);log.info(*****result: result);return result;}
}6.正常测试
启动eureka7001
启动cloud-provider-hystrix-payment8001
访问
success的方法 - http://localhost:8001/payment/hystrix/ok/1 每次调用耗费5秒钟 - http://localhost:8001/payment/hystrix/timeout/1
上述module均OK
以上述为根基平台从正确 - 错误 - 降级熔断 - 恢复。
51_JMeter高并发压测后卡顿
上述在非高并发情形下还能勉强满足
Jmeter压测测试
JMeter官网 The Apache JMeter™ application is open source software, a 100% pure Java application designed to load test functional behavior and measure performance. It was originally designed for testing Web Applications but has since expanded to other test functions. 开启Jmeter来20000个并发压死800120000个请求都去访问paymentInfo_TimeOut服务
1.测试计划中右键添加-》线程-》线程组线程组202102线程数200线程数100其他参数默认
2.刚刚新建线程组202102右键它-》添加-》取样器-》Http请求-》基本 输入http://localhost:8001/payment/hystrix/ok/1
3.点击绿色三角形图标启动。
看演示结果拖慢原因tomcat的默认的工作线程数被打满了没有多余的线程来分解压力和处理。
Jmeter压测结论
上面还是服务提供者8001自己测试假如此时外部的消费者80也来访问那消费者只能干等最终导致消费端80不满意服务端8001直接被拖慢。
52_订单微服务调用支付服务出现卡顿
看热闹不嫌弃事大80新建加入
1.新建 - cloud-consumer-feign-hystrix-order80
2.POM
?xml version1.0 encodingUTF-8?
project xmlnshttp://maven.apache.org/POM/4.0.0xmlns:xsihttp://www.w3.org/2001/XMLSchema-instancexsi:schemaLocationhttp://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsdparentartifactIdLearnCloud/artifactIdgroupIdcom.lun.springcloud/groupIdversion1.0.0-SNAPSHOT/version/parentmodelVersion4.0.0/modelVersionartifactIdcloud-consumer-feign-hystrix-order80/artifactIddependencies!--openfeign--dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-openfeign/artifactId/dependency!--hystrix--dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-netflix-hystrix/artifactId/dependency!--eureka client--dependencygroupIdorg.springframework.cloud/groupIdartifactIdspring-cloud-starter-netflix-eureka-client/artifactId/dependency!-- 引入自己定义的api通用包可以使用Payment支付Entity --dependencygroupIdcom.lun.springcloud/groupIdartifactIdcloud-api-commons/artifactIdversion${project.version}/version/dependency!--web--dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-web/artifactId/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-actuator/artifactId/dependency!--一般基础通用配置--dependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-devtools/artifactIdscoperuntime/scopeoptionaltrue/optional/dependencydependencygroupIdorg.projectlombok/groupIdartifactIdlombok/artifactIdoptionaltrue/optional/dependencydependencygroupIdorg.springframework.boot/groupIdartifactIdspring-boot-starter-test/artifactIdscopetest/scope/dependency/dependencies/project3.YML
server:port: 80eureka:client:register-with-eureka: falseservice-url:defaultZone: http://eureka7001.com:7001/eureka/
4.主启动
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.hystrix.EnableHystrix;
import org.springframework.cloud.openfeign.EnableFeignClients;/***/
SpringBootApplication
EnableFeignClients
//EnableHystrix
public class OrderHystrixMain80
{public static void main(String[] args){SpringApplication.run(OrderHystrixMain80.class,args);}
}5.业务类
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.stereotype.Component;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;/***/
Component
FeignClient(value CLOUD-PROVIDER-HYSTRIX-PAYMENT /*,fallback PaymentFallbackService.class*/)
public interface PaymentHystrixService
{GetMapping(/payment/hystrix/ok/{id})public String paymentInfo_OK(PathVariable(id) Integer id);GetMapping(/payment/hystrix/timeout/{id})public String paymentInfo_TimeOut(PathVariable(id) Integer id);
}
import com.lun.springcloud.service.PaymentHystrixService;
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.RestController;import javax.annotation.Resource;RestController
Slf4j
public class OrderHystirxController {Resourceprivate PaymentHystrixService paymentHystrixService;GetMapping(/consumer/payment/hystrix/ok/{id})public String paymentInfo_OK(PathVariable(id) Integer id){String result paymentHystrixService.paymentInfo_OK(id);return result;}GetMapping(/consumer/payment/hystrix/timeout/{id})public String paymentInfo_TimeOut(PathVariable(id) Integer id) {String result paymentHystrixService.paymentInfo_TimeOut(id);return result;}
}6.正常测试
http://localhost/consumer/payment/hystrix/ok/1
7.高并发测试
2W个线程压8001
消费端80微服务再去访问正常的Ok微服务8001地址
http://localhost/consumer/payment/hystrix/ok/32
消费者80被拖慢
原因8001同一层次的其它接口服务被困死因为tomcat线程池里面的工作线程已经被挤占完毕。
正因为有上述故障或不佳表现才有我们的降级/容错/限流等技术诞生。
53_降级容错解决的维度要求
超时导致服务器变慢(转圈) - 超时不再等待
出错(宕机或程序运行出错) - 出错要有兜底
解决
对方服务(8001)超时了调用者(80)不能一直卡死等待必须有服务降级。对方服务(8001)down机了调用者(80)不能一直卡死等待必须有服务降级。对方服务(8001)OK调用者(80)自己出故障或有自我要求(自己的等待时间小于服务提供者)自己处理降级。
54_Hystrix之服务降级支付侧fallback
降级配置 - HystrixCommand
8001先从自身找问题
设置自身调用超时时间的峰值峰值内可以正常运行超过了需要有兜底的方法处埋作服务降级fallback。
8001fallback
业务类启用 - HystrixCommand报异常后如何处理
—旦调用服务方法失败并抛出了错误信息后会自动调用HystrixCommand标注好的fallbackMethod调用类中的指定方法
Service
public class PaymentService{HystrixCommand(fallbackMethod paymentInfo_TimeOutHandler/*指定善后方法名*/,commandProperties {HystrixProperty(nameexecution.isolation.thread.timeoutInMilliseconds,value3000)})public String paymentInfo_TimeOut(Integer id){//int age 10/0;try { TimeUnit.MILLISECONDS.sleep(5000); } catch (InterruptedException e) { e.printStackTrace(); }return 线程池: Thread.currentThread().getName() id: id\tO(∩_∩)O哈哈~ 耗时(秒): ;}//用来善后的方法public String paymentInfo_TimeOutHandler(Integer id){return 线程池: Thread.currentThread().getName() 8001系统繁忙或者运行报错请稍后再试,id: id\to(╥﹏╥)o;}}上面故意制造两种异常:
int age 10/0计算异常我们能接受3秒钟它运行5秒钟超时异常。
当前服务不可用了做服务降级兜底的方案都是paymentInfo_TimeOutHandler
主启动类激活
添加新注解EnableCircuitBreaker
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.circuitbreaker.EnableCircuitBreaker;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;SpringBootApplication
EnableEurekaClient
EnableCircuitBreaker//添加到此处
public class PaymentHystrixMain8001{public static void main(String[] args) {SpringApplication.run(PaymentHystrixMain8001.class, args);}
}55_Hystrix之服务降级订单侧fallback
80订单微服务也可以更好的保护自己自己也依样画葫芦进行客户端降级保护
题外话切记 - 我们自己配置过的热部署方式对java代码的改动明显
但对HystrixCommand内属性的修改建议重启微服务
YML
server:port: 80eureka:client:register-with-eureka: falseservice-url:defaultZone: http://eureka7001.com:7001/eureka/#开启
feign:hystrix:enabled: true主启动
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.hystrix.EnableHystrix;
import org.springframework.cloud.openfeign.EnableFeignClients;SpringBootApplication
EnableFeignClients
EnableHystrix//添加到此处
public class OrderHystrixMain80{public static void main(String[] args){SpringApplication.run(OrderHystrixMain80.class,args);}
}
业务类
import com.lun.springcloud.service.PaymentHystrixService;
import com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand;
import com.netflix.hystrix.contrib.javanica.annotation.HystrixProperty;
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.RestController;import javax.annotation.Resource;RestController
Slf4j
public class OrderHystirxController {Resourceprivate PaymentHystrixService paymentHystrixService;GetMapping(/consumer/payment/hystrix/timeout/{id})HystrixCommand(fallbackMethod paymentTimeOutFallbackMethod,commandProperties {HystrixProperty(nameexecution.isolation.thread.timeoutInMilliseconds,value1500)})public String paymentInfo_TimeOut(PathVariable(id) Integer id) {//int age 10/0;String result paymentHystrixService.paymentInfo_TimeOut(id);return result;}//善后方法public String paymentTimeOutFallbackMethod(PathVariable(id) Integer id){return 我是消费者80,对方支付系统繁忙请10秒钟后再试或者自己运行出错请检查自己,o(╥﹏╥)o;}}
