SpringBoot:开发框架
Eureka:注册中心
ribbon: 实现负载均衡
maven: 管理项目
1、首先简单描述一下 此微服务结构图:
2、创建的详细流程:
1)注册中心Eureka服务端实现:
1、 start.spring.io 去找模板,自己加依赖EurekaServer
2、在eclipse中创建SpringBoot项目,结构如图:(jdk版本不一致还需要自己去修改,本文不作详细描述)
3、 将pom.xml文件内容替换成刚刚下载的sd-Eureka-server.zip中pom.xml(需要提前配置好maven)
本文pom文件参考如下: jar包下载完成,项目中多了Maven Dependenties目录。
<?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>2.1.6.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>sd-Eureka-Server</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>sd-Eureka-Server</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
<spring-cloud.version>Greenwich.SR1</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>
</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>
4、添加启动类,启动Eureka注册中心
在java路径下创建包com.example,包内创建类EurekaServerRunApp.java,内容如下:
(其实也可以把刚sd-Eureka-server.zip 中src目录直接替换,这里我自己写的,正好复习下)
EurekaServerRunApp.java
package com.example;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;
//启动Eureka服务
@EnableEurekaServer
@SpringBootApplication
public class EurekaServerRunApp {
public static void main(String[] args) {
SpringApplication.run(EurekaServerRunApp.class, args);
}
}
5、在resources目录下添加配置文件application.yml,内容如下:
security:
basic:
enabled: true
user:
name: user
password: password123
server:
port: 8761
eureka:
client:
register-with-eureka: false
fetch-registry: false
service-url:
defaultZone: http://user:password123@localhost:8761/eureka
logging:
level:
root: INFO
6、接下来就是启动服务,网页中查看效果了,如图:
启动:
到此,Eureka服务端创建并启动完成!
2)接下来我们创建服务提供者1(项目名称:provider-user1)
1、也是到 Start.spring.io去下载模板,这次选择的依赖有两个 EurekaClient,Web 如图:
2、创建 maven项目,pom.xml改成刚刚下载的zip文件中的,新增application.yml文件
pom.xml
<?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>2.1.6.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>sd-provider-user1</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>sd-provider-user1</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
<spring-cloud.version>Greenwich.SR1</spring-cloud.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</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>
com.example包下新建启动文件ProviderUserRunApp.java
package com.example;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
//启动Eureka客户端
@EnableEurekaClient
@SpringBootApplication
public class ProviderUserRunApp {
public static void main(String[] args) {
SpringApplication.run(ProviderUserRunApp.class, args);
}
}
resources目录下新增application.yml文件:
server:
port: 7900
spring:
application:
name: provider-user
eureka:
client:
serviceUrl:
defaultZone: http://user:password123@localhost:8761/eureka
logging:
level:
root: INFO
3、添加业务代码,直接访问web项目
添加包com.example.controller ,包内添加 HelloController.java类
package com.example.controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class HelloController {
@GetMapping("/hello/{name}")
public String hello(@PathVariable String name) {
return "1:"+name;
}
}
4、启动服务,查看效果,网页输入:http://localhost:8761/
3)我们以同样的方式去创建服务提供者2(provider-user2)
注意,只需要将提供者1中的application.yml文件中端口号修改即可拿来复用,如改为8010
启动provider-user2,再次刷新网址:http://localhost:8761/
4)最后,让我们创建服务消费者
1、start.spring.io中创建模板,仍然选择 EurekaClient 和web两个依赖(与provider-user一样,不再赘述)
2、创建Customer-Client
修改pom.xml
<?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>2.1.6.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>sd-provider-user1</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>sd-provider-user1</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
<spring-cloud.version>Greenwich.SR1</spring-cloud.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</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>
添加application.yml
server:
port: 8050
spring:
application:
name: consumer-client
eureka:
client:
serviceUrl:
defaultZone: http://user:password123@localhost:8761/eureka
logging:
level:
root: INFO
3、添加启动文件(注意与前面不一样了)
package com.example;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.context.annotation.Bean;
import org.springframework.web.client.RestTemplate;
@SpringBootApplication
@EnableEurekaClient
public class ConsumerRunApp {
//创建对象
@Bean
@LoadBalanced //实现负载均衡,不加该注解无法实现通过服务提供者名称访问
public RestTemplate restTemplate(){
return new RestTemplate();
}
public static void main(String[] args) {
SpringApplication.run(ConsumerRunApp.class, args);
}
}
4、添加业务代码(注意与前面不一样了)
package com.example.controller;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;
@RestController
public class HelloController {
@Autowired
private RestTemplate restTemplate;
@GetMapping("/hello/{name}")
@ResponseBody
public String hello(@PathVariable String name){
String url = "http://provider-user/hello/"+name;
return this.restTemplate.getForObject(url, String.class);
}
}
5、启动
最后,我们演示下效果,在浏览器中输入:
http://localhost:8050/hello/tony
反复刷新页面时,浏览器中交替显示 : 1tony 2tony 1tony 2tony 1tony 2tony
可见加了@LoadBalanced注解后,实现了在两个服务提供者之间的负载均衡。
代码下载请见个人github:https://github.com/fuhongyu/SpringBoot-demo