源碼
GitHub:https://github.com/291685399/springcloud-learning/tree/master/springcloud-eureka03
目标
上一篇SpringCloud(二)eureka注冊中心的使用介紹如何使用eureka,但是在實際使用中,一般都是叢集,下面介紹如何給eureka server搭建叢集,同時client連接配接叢集
eureka的使用
- 建立一個父工程,命名為springcloud-eureka03
目錄結構如下圖:
![](https://img.laitimes.com/img/9ZDMuAjOiMmIsIjOiQnIsIyZuBnL4kjNwAjN1ATMyIjNwkTMwIzLc52YucWbp5GZzNmLn9Gbi1yZtl2Lc9CX6MHc0RHaiojIsJye.png)
pom.xml:
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.4.RELEASE</version>
<relativePath/>
</parent>
<dependencies>
<!-- springboot -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
- 建立子產品,命名為eureka-server03_1
目錄結構如下圖:
pom.xml:
<parent>
<groupId>com.wyj</groupId>
<artifactId>springcloud-eureka03</artifactId>
<version>0.0.1-SNAPSHOT</version>
</parent>
<properties>
<java.version>1.8</java.version>
<spring-cloud.version>Finchley.SR1</spring-cloud.version>
</properties>
<dependencies>
<!-- springcloud eureka server -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
在啟動器EurekaServer03_1Application上添加注解用于開啟eureka server
@SpringBootApplication
@EnableEurekaServer
public class EurekaServer03_1Application {
public static void main(String[] args) {
SpringApplication.run(EurekaServer03_1Application.class, args);
}
}
在application.properties:
注意:
1、這裡的端口,eureka-server03_1的端口是10000,後面建立的子產品eureka-server03_2端口為10001,是以它需要連接配接的eureka server位址為http://127.0.0.1:10001/eureka,當然eureka-server03_2需要連接配接的eureka-server位址為http://127.0.0.1:10000/eureka,這樣才能給eureka server形成一個叢集
2、需要将之前使用eureka配置中的eureka.client.register-with-eureka=false和eureka.client.fetch-registry=false注釋
server.port=10000
spring.application.name:eureka-server
# 是否注冊自己的資訊到EurekaServer,預設是true
#eureka.client.register-with-eureka=false
# 是否拉取其它服務的資訊,預設是true
#eureka.client.fetch-registry=false
# EurekaServer的位址,現在是自己的位址,如果是叢集,需要加上其它Server的位址
eureka.client.service-url.defaultZone:http://127.0.0.1:10001/eureka
- 建立子產品,命名為eureka-server03_2
目錄結構如下圖:
pom.xml:
<parent>
<groupId>com.wyj</groupId>
<artifactId>springcloud-eureka03</artifactId>
<version>0.0.1-SNAPSHOT</version>
</parent>
<properties>
<java.version>1.8</java.version>
<spring-cloud.version>Finchley.SR1</spring-cloud.version>
</properties>
<dependencies>
<!-- springcloud eureka server -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
在啟動器EurekaServer03_2Application上添加注解用于開啟eureka server
@SpringBootApplication
@EnableEurekaServer
public class EurekaServer03_2Application {
public static void main(String[] args) {
SpringApplication.run(EurekaServer03_2Application.class, args);
}
}
在application.properties:
注意:
1、這裡的端口,eureka-server03_1的端口是10000,後面建立的子產品eureka-server03_2端口為10001,是以它需要連接配接的eureka server位址為http://127.0.0.1:10000/eureka,當然eureka-server03_2需要連接配接的eureka-server位址為http://127.0.0.1:10000/eureka,這樣才能給eureka server形成一個叢集
2、需要将之前使用eureka配置中的eureka.client.register-with-eureka=false和eureka.client.fetch-registry=false注釋
server.port=10000
spring.application.name:eureka-server
# 是否注冊自己的資訊到EurekaServer,預設是true
#eureka.client.register-with-eureka=false
# 是否拉取其它服務的資訊,預設是true
#eureka.client.fetch-registry=false
# EurekaServer的位址,現在是自己的位址,如果是叢集,需要加上其它Server的位址
eureka.client.service-url.defaultZone:http://127.0.0.1:10001/eureka
- 建立子產品,命名為eureka-provider03
目錄結構如下圖:
pom.xml:
<parent>
<groupId>com.wyj</groupId>
<artifactId>springcloud-eureka03</artifactId>
<version>0.0.1-SNAPSHOT</version>
</parent>
<properties>
<java.version>1.8</java.version>
<spring-cloud.version>Finchley.SR1</spring-cloud.version>
</properties>
<dependencies>
<!-- springdatajpa -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<!-- springboot -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- mysql -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<!-- lombok -->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<!-- springcloud eureka client -->
<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>
在啟動器EurekaProvider03Application上添加注解用于開啟eureka client
@SpringBootApplication
@EnableDiscoveryClient
public class EurekaProvider03Application{
public static void main(String[] args) {
SpringApplication.run(EurekaProvider03Application.class, args);
}
}
ProviderController:
@Controller
public class ProviderController {
@Autowired
private UserService userService;
@RequestMapping(value = "/findById/{id}")
@ResponseBody
public User findById(@PathVariable int id) {
User user = userService.findById(id);
return user;
}
}
UserService:
public interface UserService {
public User findById(int id);
}
UserServiceImpl:
@Service
public class UserServiceImpl implements UserService {
@Autowired
private UserRepository userRepository;
@Override
public User findById(int id) {
Optional<User> userOptional = userRepository.findById(id);
User user = userOptional.get();
return user;
}
}
UserRepository:
public interface UserRepository extends JpaRepository<User, Integer> {
}
User:
@Entity
@Data
public class User implements Serializable {
@Id
@GeneratedValue
private int id;
private String name;
private String sex;
private int age;
private String address;
private String phone;
}
application.properties:
注意:
這裡eureka server的位址應該是多個,因為eureka server是叢集
server.port=8081
### datasource ###
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/springcloud-eureka01?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8&useSSL=true
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.username=root
spring.datasource.password=root
### springdatajpa ###
#列印出自動生産的SQL,友善調試的時候檢視
spring.jpa.show-sql=true
#更新資料庫表結構
spring.jpa.hibernate.ddl-auto= update
#對列印的sql進行格式化,友善檢視
spring.jpa.properties.hibernate.format_sql= true
spring.jpa.properties.hibernate.use_sql_comments=true
#指定生成表名的存儲引擎為InneoDB
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL5InnoDBDialect
# springcloud
spring.application.name=eureka-provider
# EurekaServer位址,因為EurekaServer不止一個,是以注冊服務的時候,EurekaServer位址,多個位址以','隔開
eureka.client.service-url.defaultZone=http://127.0.0.1:10000/eureka,http://127.0.0.1:10001/eureka
# 當調用getHostname擷取執行個體的hostname時,傳回ip而不是host名稱
eureka.instance.prefer-ip-address=true
eureka.instance.ip-address=127.0.0.1
- 建立子產品,命名為eureka-consumer03
目錄結構如下圖:
pom.xml:
<parent>
<groupId>com.wyj</groupId>
<artifactId>springcloud-eureka03</artifactId>
<version>0.0.1-SNAPSHOT</version>
</parent>
<properties>
<java.version>1.8</java.version>
<spring-cloud.version>Finchley.SR1</spring-cloud.version>
</properties>
<dependencies>
<!-- springboot -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- lombok -->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<!-- springcloud eureka client -->
<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>
在啟動器EurekaConsumer03Application上添加注解用于開啟eureka client
@SpringBootApplication
@EnableDiscoveryClient
public class EurekaConsumer03Application{
public static void main(String[] args) {
SpringApplication.run(EurekaConsumer03Application.class, args);
}
}
ConsumerController:
@Controller
public class ConsumerController{
@Autowired
private RestTemplate restTemplate;
// Eureka用戶端,可以擷取到服務執行個體資訊
@Autowired
private DiscoveryClient discoveryClient;
@RequestMapping(value = "/findById/{id}")
@ResponseBody
public User findById(@PathVariable int id) {
// 根據服務名稱,擷取服務執行個體
List<ServiceInstance> instances = discoveryClient.getInstances("eureka-provider");
// 因為隻有一個UserService,是以我們直接get(0)擷取
ServiceInstance instance = instances.get(0);
String baseUrl = "http://" + instance.getHost() + ":" + instance.getPort();
System.out.println("baseUrl=" + baseUrl);
User user = restTemplate.getForObject(baseUrl + "/findById/" + id, User.class);
return user;
}
}
RestConfig:
@Configuration
public class RestConfig {
@Bean
public RestTemplate restTemplate() {
return new RestTemplate();
}
}
User:
@Data
public class User implements Serializable {
private int id;
private String name;
private String sex;
private int age;
private String address;
private String phone;
}
application.properties:
注意:
這裡eureka server的位址應該是多個,因為eureka server是叢集
server.port=8080
# springcloud
spring.application.name=eureka-consumer
# EurekaServer位址,因為EurekaServer不止一個,是以注冊服務的時候,EurekaServer位址,多個位址以','隔開
eureka.client.service-url.defaultZone=http://127.0.0.1:10000/eureka,http://127.0.0.1:10001/eureka
# 當調用getHostname擷取執行個體的hostname時,傳回ip而不是host名稱
eureka.instance.prefer-ip-address=true
測試使用
分别啟動eureka-server03_1、eureka-server03_2、eureka-provider03和eureka-consumer03
注意:
兩個server先啟動的server會報錯,如下圖:
然後另外一台server啟動後就不報錯了,這是正确的,因為先啟動的那台server不能找到另外一台形成叢集,就報錯了,當另外一台server啟動時,找到了,就不報錯了。
- 通路
浏覽器通路http://127.0.0.1:8080/findById/1
-
通路eureka
http://127.0.0.1:10000/ (這裡通路的是端口号為10000的server)通路http://127.0.0.1:10001/也是一樣的
可以看到目前有eureka-consumer、eureka-provider兩個執行個體和eureka-server形成的叢集SpringCloud(四)eureka注冊中心叢集的使用