【SpringCloud】Eureka-实例

Eureka介绍

之前总结的博客，看完介绍，再看实例可能理解的会更好。

https://blog.csdn.net/wangyunzhao007/article/details/105622319

Eureka实例

一下三个微服务均是用idea创建maven项目。

1.注册中心

pom依赖

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.6.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>cn.itcast.eureka</groupId>
    <artifactId>itcast-eureka</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>itcast-eureka</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <spring-cloud.version>Hoxton.SR3</spring-cloud.version>
    </properties>

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

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

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

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>
           

 yml配置

server:
  port: 10086
spring:
  application:
    name: itcast-eureka

eureka:
  client:
    service-url:
      defaultZone: http://localhost:10086/eureka/
  server:
    eviction-interval-timer-in-ms: 5000 #剔除无效链接的间隔时间
    enable-self-preservation: false #关闭自我保护状态
           

 启动类（启动类所在位置应能够扫描到该项目下所有的类）

@SpringBootApplication(exclude= {DataSourceAutoConfiguration.class})
@EnableEurekaServer  //启动eureka服务端
public class ItcastEurekaApplication {

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

}
           

 当启动此服务后，在浏览器上，输入http://localhost:10086/

2.注册中心服务端

pom依赖

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.6.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.test</groupId>
    <artifactId>day01</artifactId>
    <version>1.0.0-SNAPSHOT</version>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Hoxton.SR3</spring-cloud.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.3.2</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
    </dependencies>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>
           

yml配置

server:
  port: 8079
spring:
  application:
    name: service-provider
eureka:
  client:
    service-url:
      defaultZone: http://localhost:10086/eureka/
    register-with-eureka: true #服务启动方启动时，会检测该参数是否为true，true会注册给eureka
           

启动类

@SpringBootApplication(exclude= {DataSourceAutoConfiguration.class})
@EnableEurekaClient   //启动eureka客户端，@enableEurekaClient
public class ServiceProviderApplication {

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

}
           

controller

@RestController
@RequestMapping("test")
public class TestController {
    @GetMapping("{id}")
    public String queryUserById(@PathVariable("id") String id){
        return id;
    }
}
           

 启动成功后，在localhost:10086页面如下如所示，多了一个服务

测试一下自己的接口也是可以的，如图：

 3.注册中心客户端

pom依赖

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.6.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.test</groupId>
    <artifactId>consumer</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <java.version>1.8</java.version>
        <spring-cloud.version>Hoxton.SR3</spring-cloud.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>io.swagger</groupId>
            <artifactId>swagger-annotations</artifactId>
            <version>1.5.19</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-swagger2</artifactId>
            <version>2.9.2</version>
        </dependency>
        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-swagger-ui</artifactId>
            <version>2.9.2</version>
        </dependency>
        <dependency>
            <groupId>tk.mybatis</groupId>
            <artifactId>mapper-spring-boot-starter</artifactId>
            <version>2.0.4</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
    </dependencies>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>${spring-cloud.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>
           

yml配置

server:
  port: 80
spring:
  application:
    name: service-consumer
eureka:
  client:
    service-url:
      defaultZone: http://localhost:10086/eureka/
    registry-fetch-interval-seconds: 5
    fetch-registry: true  #开启拉取服务
           

启动类

@SpringBootApplication(exclude= {DataSourceAutoConfiguration.class})
@EnableEurekaClient
public class ServiceConsumerApplication {
    @Bean
    public RestTemplate restTemplate(){
        return new RestTemplate();
    }


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

}
           

controller

@RestController
@RequestMapping("consumer/test")
public class TestController {
    @Autowired
    private RestTemplate restTemplate;

    @Autowired
    private DiscoveryClient discoveryClient;  //拉取所有的服务信息

    @GetMapping
    @ResponseBody
    public String test(@RequestParam("id") String id){

        //可能会有多个同名服务，故使用list
        List<ServiceInstance> instances = discoveryClient.getInstances("service-provider");
        ServiceInstance instance = instances.get(0);
        return this.restTemplate.getForObject("http://"+instance.getHost()+":"+ instance.getPort() +"/test/" + id,String.class);
//        直接通过地址和端口调用，没有通过服务区调用
//        return this.restTemplate.getForObject("http://localhost:8079/test/"+id , String.class);

    }

}
           

最后调用此客户端的接口，效果如下：