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文章目录

• • 云原生技术-微服务SpringCloud(1)
  • • 搭建提供者、消费者模块
    • 引入注册中心SpringCloud Eureka
    • • • Bug：引入Eureka后报错。
    • 搭建Eureka集群
    • 搭建提供者集群(为了负载均衡)
    • • • Bug：ribbon+restTemplate报错
      • 使用actuator功能
    • Feign/OpenFeign
    • • • Bug：OpenFeign调用失败报错405

云原生技术-微服务SpringCloud(1)

搭建提供者、消费者模块

1：创建一个空Maven项目，删除src目录

2：父POM

 <!--    修改打包方式为pom-->
    <packaging>pom</packaging>

    <properties>
        <!--        springcloud的版本-->
        <spring.cloud-version>Hoxton.RELEASE</spring.cloud-version>
<!--        springBoot的版本-->
        <spring.boot-version>2.2.4.RELEASE</spring.boot-version>

<!--        防止idea发疯，编译一直都是java5-->
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <maven.compiler.source>10</maven.compiler.source>
        <maven.compiler.target>10</maven.compiler.target>
        <encoding>UTF-8</encoding>



    </properties>

    <!--    dependencyManagement是用定义依赖的，并没有直接引入依赖，作用是控制父子模块的依赖版本一致性问题,
    子模块通过不加version，version会自动的去父pom找到定义好的依赖版本，这样兼容性就会大大提升
    -->

    <dependencyManagement>
        <!--  springcloud总依赖-->
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring.cloud-version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
            <!--springBoot总依赖-->
            <dependency>

                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-dependencies</artifactId>
                <version>${spring.boot-version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>

<!--            引入Mybatis-->
<!--            注意：一定要导入mybatis的springBoot启动器，不要直接导入mybatis依赖，不然会没效果-->
            <dependency>
                <groupId>org.mybatis.spring.boot</groupId>
                <artifactId>mybatis-spring-boot-starter</artifactId>
                <version>1.3.1</version>
            </dependency>

            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>5.1.47</version>
            </dependency>

<!--            druid数据库连接池-->
            <dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>druid</artifactId>
                <version>1.0.9</version>
            </dependency>

        </dependencies>


    </dependencyManagement>


    <build>
<!--      mybatis的静态资源过滤，也就是过滤Mapper.xml，我们也可以这样想，xml文件是放在resources目录下的，放在java
目录下不会被扫描，所以我们要过滤java目录中的xml
-->
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.xml</include>
                </includes>
                <filtering>true</filtering>
            </resource>
        </resources>
    </build>

3.创建一个子模块，作微服务的提供者，端口号为8001

里面代码如下。。。

deptController

@RestController
public class deptController {

    private deptService deptService;

    @Autowired
    @Qualifier("deptServiceImpl")
    public void setDeptService(com.boot.service.deptService deptService) {
        this.deptService = deptService;
    }
    @GetMapping(path = "/queryAllDept")
    public List<dept> queryAllDept(){


        return deptService.queryAllDept();
    }



}

dao层。deptMapper

@Mapper //把这个Mapper接口变成可以注入的Bean,*****一定要。
@Repository  //变成组件  ***一定要
public interface deptMapper {

    List<dept> queryAllDept();
 
}

Mapper.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.boot.dao.deptMapper">

    <select id="queryAllDept" resultType="com.pojo.dept">
        select deptid,deptName from dept;
    </select>
 
</mapper>

service层省略，和普通springBoot项目构建是一样的

application.yml(8001)

server:
  port: 8001

spring:
  application:
#    微服务名
    name: provider_dept8001/8002
  datasource:
    url: jdbc:mysql://localhost:3306/ssmrl?serverTimezone=UTC
    driver-class-name: com.mysql.jdbc.Driver
    username: root
    password: 18420163207
    type: com.alibaba.druid.pool.DruidDataSource

创建一个子模块(springcloud-02-api)，专门放实体类

public class dept implements Serializable {

    private String deptid;
    private String deptName;

    public dept() {
    }

    public dept(String deptid, String deptName) {
        this.deptid = deptid;
        this.deptName = deptName;
    }

    public String getDeptid() {
        return deptid;
    }

    public void setDeptid(String deptid) {
        this.deptid = deptid;
    }

    public String getDeptName() {
        return deptName;
    }

    public void setDeptName(String deptName) {
        this.deptName = deptName;
    }

    @Override
    public String toString() {
        return "dept{" +
                "deptid='" + deptid + '\'' +
                ", deptName='" + deptName + '\'' +
                '}';
    }
}

创建另外一个子模块，springcloud-02-provider-dept8002

把springcloud-02-provider-dept8001代码全部复制上去，修改配置文件application.yml(8002)

server:
  port: 8002

spring:
  application:
#    微服务名
    name: provider_dept8001/8002
  datasource:
    url: jdbc:mysql://localhost:3306/ssmrl?serverTimezone=UTC
    driver-class-name: com.mysql.jdbc.Driver
    username: root
    password: 18420163207
    type: com.alibaba.druid.pool.DruidDataSource

为什么我们要复制多一份微服务提供者代码？

因为考虑到后面我们要使用负载均衡ribbon或者openFeign（不过底层也是ribbon）

4.创建子模块springcloud-02-comsumer-dept80

controller层：

@RestController
public class deptController80 {

    @Autowired
    private RestTemplate restTemplate;
    private final String URL_DEPT="http://localhost:8001/";


    @GetMapping("/comsumer/queryAllDept")
    public List<dept> queryAllDept80(){
        List<dept> res = restTemplate.getForObject(URL_DEPT + "queryAllDept", List.class);

        return res;
    }

}

因为默认的RestTemplate没有放入IOC容器中（也就是没有Bean），我们需要手动的放入IOC容器

config层

@Configuration
public class restTemplateConfig {

    @Bean
    public RestTemplate restTemplate(){

        return new RestTemplate();
    }

}

application.yml(80)

server:
  port: 80

#
spring:
  application:
    name: comsumer_dept80

为什么微服务消费者层的端口是80，因为80端口可以省略不写，就比如我们打开百度，也是不需要写端口号的，因为微服务消费者层是给用户去访问的

消费者层只需要Controller去远程调用提供者的Controller方法即可，所以消费者层—不能—有dao，service层

这样提供者和消费者就搭建好了，接下来我们可以引入SpringCloud组件了。。。。。。。

---

引入注册中心SpringCloud Eureka

配置如下：

创建子模块springcloud-02-eureka7001(eureka注册中心服务端)

pom.xml

 <dependencies>

        <!--      web和actuator是必备的，******除了gateway网关不能加入web包  -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <!--        actuator用来监控-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>


<!--        eureka Server-->
          <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
        </dependency>





    </dependencies>

eureka模块主启动类

@SpringBootApplication
@EnableEurekaServer //开启Eureka服务器
public class SpringBootApplication7001 {

    public static void main(String[] args) {
        SpringApplication.run(SpringBootApplication7001.class,args);
    }

}

application.yml(7001)

server:
  port: 7001


#  配置eureka
eureka:
  instance:
    hostname: eureka-server7001.com
  client:
    register-with-eureka: false
    fetchRegistry: false
    service-url:
      defaultZone: http://${eureka.instance.hostname}:7001/eureka/

给提供者springcloud-02-provider-dept8001和8002修改如下

@SpringBootApplication
@EnableEurekaClient //eureka客户端
public class SpringBootApplication8001 {

    public static void main(String[] args) {
        SpringApplication.run(SpringBootApplication8001.class,args);


    }

}

server:
  port: 8001

spring:
  application:
#    微服务名
    name: provider_dept  
  datasource:
    url: jdbc:mysql://localhost:3306/ssmrl?serverTimezone=UTC
    driver-class-name: com.mysql.jdbc.Driver
    username: root
    password: 18420163207
    type: com.alibaba.druid.pool.DruidDataSource


#    eureka Client
eureka:
  client:
    service-url:
      defaultZone: http://eureka-server7001.com:7001/eureka/
    register-with-eureka: true
    fetch-registry: false
  instance:
    instance-id: eureka-client8001

server:
  port: 8002

spring:
  application:
#    微服务名
    name: provider_dept
  datasource:
    url: jdbc:mysql://localhost:3306/ssmrl?serverTimezone=UTC
    driver-class-name: com.mysql.jdbc.Driver
    username: root
    password: 18420163207
    type: com.alibaba.druid.pool.DruidDataSource


#   eureka
eureka:
  client:
    fetch-registry: false
    register-with-eureka: true
    service-url:
      defaultZone: http://eureka-server7001.com:7001/eureka/
  instance:
    prefer-ip-address: true
    instance-id: eureka-client8002

Bug：引入Eureka后报错。

。。。取名要规范。。。

搭建Eureka集群

创建springcloud-02-eureka7002和7003两个模块

application.yml（7001）

server:
  port: 7001


#  配置eureka
eureka:
  instance:
    hostname: eureka-server7001.com
  client:
    register-with-eureka: false
    fetchRegistry: false
    service-url:
      defaultZone: http://eureka-server7002.com:7002/eureka/,http://eureka-server7003.com:7003/eureka/   #集群版就修改这个。单机认自己，集群认其他
      
      

application.yml（7002）

server:
  port: 7002

spring:
  application:
    name: eureka7002   #这里可有可无，除了微服务提供者。

eureka:
  instance:
    hostname: eureka-server7002.com
  client:
    fetch-registry: false
    register-with-eureka: false
    service-url:
      defaultZone: http://eureka-server7001.com:7001/eureka/,http://eureka-server7003.com:7003/eureka/

application.yml（7003）

server:
  port: 7003

spring:
  application:
    name: eureka7003

eureka:
  instance:
    hostname: eureka-server7003.com
  client:
    register-with-eureka: false
    fetch-registry: false
    service-url:
      defaultZone: http://eureka-server7001.com:7001/eureka/,http://eureka-server7002.com:7002/eureka/

其实Eureka集群没啥变化，也就是修改了serviceUrl的defaultZone罢了。记住一句话，单机版认自己，集群版认其他

搭建提供者集群(为了负载均衡)

在8001和8002微服务中修改defaultZone。

eureka:
  client:
    service-url:
      defaultZone: http://eureka-server7001.com:7001/eureka/, http://eureka-server7002.com:7002/eureka/, http://eureka-server7003.com:7003/eureka/

还有8001和8002的微服务名要一致（spring.application.name）

spring:
  application:
#    微服务名
    name: provider-dept  #8001和8002要一致

在springcloud-02-comsumer-dept80消费者层

@Configuration
public class restTemplateConfig {


    @Bean
    @LoadBalanced //开启负载均衡
    public RestTemplate restTemplate(){

        return new RestTemplate();
    }



}

@SpringBootApplication
@EnableEurekaClient
public class SpringBootApplication80 {

    public static void main(String[] args) {
        SpringApplication.run(SpringBootApplication80.class,args);
    }


}

用Ribbon+RestTemplate员工调用提供者的Controller方法

@RestController
public class deptController80 {

    @Autowired
    private RestTemplate restTemplate;
    private final String URL_DEPT="http://PROVIDER-DEPT/"; //实现负载均衡用提供者微服务名代替IP:Port



    @GetMapping("/comsumer/queryAllDept")
    public List<dept> queryAllDept80(){
        List<dept> res = restTemplate.getForObject(URL_DEPT + "queryAllDept", List.class);

        return res;
    }


}

application.yml(80)

server:
  port: 80

#
spring:
  application:
    name: comsumer-dept80
eureka:
  client:
    fetch-registry: true
    register-with-eureka: false
    service-url:
      defaultZone: http://eureka-server7001.com:7001/eureka/,http://eureka-server7002.com:7002/eureka/,http://eureka-server7003.com:7003/eureka/

Bug：ribbon+restTemplate报错

ribbon不支持微服务名有下划线（_）,修改过来即可

spring:
  application:
#    微服务名
    name: provider-dept

使用actuator功能

#暴露端点。使用actuator功能
management:
  endpoints:
    web:
      exposure:
        include: "*"

Feign/OpenFeign

创建子模块springcloud-02-comsumer-openFeign-dept80

所需的依赖

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

点进去看看

我们可以发现，Feign/openFeign的底层就是Ribbon，所以openFeign自带了负载均衡的功能，相较于Ribbon+restTemplate，openFeign无需手动的使用@LoadBalanced注解来开启负载均衡，而Ribbon需要在restTemplate的Bean上加这个注解才有负载均衡的能力

主启动类

@SpringBootApplication
@EnableFeignClients //开启Feign的客户端支持
public class springApplicationFeign80 {

    public static void main(String[] args) {

        SpringApplication.run(springApplicationFeign80.class,args);

    }



}

编写微服务接口

@Service
@FeignClient("PROVIDER-DEPT") //标注这个微服务接口是属于“PROVIDER-DEPT”这个微服务的
public interface deptService {
    
    //下面的代码直接从微服务提供者的controller复制过来即可
    @GetMapping(path = "/queryAllDept")
    public List<dept> queryAllDept();



}

然后便是使用

@RestController
public class deptController {

    @Autowired
    private deptService deptService;


    @RequestMapping("/feign/queryAllDept")
    public List<dept> queryAllDept(){

        return deptService.queryAllDept();
    }



}

Bug：OpenFeign调用失败报错405

错误类型：

原因是我们没有在提供者加上@PathVariable或者@RequestParam注解

解决方法一：在提供者加上@RequestParam注解（每个提供者传入的参数都要加上这个注解）

@RestController
public class deptController {

    private deptService deptService;

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


    @Autowired
    @Qualifier("deptServiceImpl")
    public void setDeptService(com.boot.service.deptService deptService) {
        this.deptService = deptService;
    }

    @GetMapping(path = "/queryAllDept")
    @HystrixCommand(fallbackMethod = "queryAllDept_Hystrix",commandProperties = {
            @HystrixProperty(name = "circuitBreaker.enabled",value = "true"),
            @HystrixProperty(name = "circuitBreaker.requestVolumeThreshold",value = "10"),
            @HystrixProperty(name = "circuitBreaker.sleepWindowInMilliseconds",value = "20000"),//注意这是毫秒。1秒=1000毫秒
            @HystrixProperty(name = "circuitBreaker.errorThresholdPercentage",value = "50")

    })
    public List<dept> queryAllDept(@RequestParam("id") String id){
        List<dept> depts = deptService.queryAllDept();
        depts.add(new dept("999",port));
        if(Integer.parseInt(id)<0){
            throw new RuntimeException();
        }

        return depts;
    }

    /**
     * 服务熔断
     */
    public List<dept> queryAllDept_Hystrix(@RequestParam("id") String id){

        List<dept> depts = deptService.queryAllDept();
        depts.add(new dept("1066","Break"));
        return depts;
    }

}

修改openFeign的微服务接口

@Service
@FeignClient("PROVIDER-DEPT")
public interface deptService {
    @GetMapping(path = "/queryAllDept")
    public List<dept> queryAllDept(@RequestParam("id") String id);
}

没有报错了！！！

解决方法二：在微服务提供者加上@PathVariable注解。。

省略！！！

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