SpringCloud学习记录
参考：《Spring Cloud 微服务实战》
使用：SpringBoot
一：创建一个SpringBoot项目：springclouddemo1
文件只有5个，
1、启动类Springclouddemo1Application.java
package com.demo;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
@EnableDiscoveryClient //激活Eureka中的DiscoveryClient实现（自动化配置，创建DiscoveryClient接口针对Eureka客户端的
//EurekaDiscoveryClient实例），才能实现上述Controller中对服务信息的输出
@SpringBootApplication
public class Springclouddemo1Application {
public static void main(String[] args) {
SpringApplication.run(Springclouddemo1Application.class, args);
}
}
2、HelloController
package com.demo.web;
import org.apache.log4j.Logger;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class HelloController {
private final Logger logger = Logger.getLogger(HelloController.class);
@Autowired
private DiscoveryClient client;
@RequestMapping("/hello")
public String hello() {
ServiceInstance instance = client.getLocalServiceInstance();
logger.info("/hello,host:"+instance.getHost()+",service_id:"+instance.getServiceId());
return "Hello Spring Cloud!";
}
}
3、application.properties
server.port=8888
spring.application.name=hello-service
eureka.client.serviceUrl.defaultZone=http://localhost:1111/eureka/4、pom.xml(重点：1.3.7版本亲测有效)
4.0.0
com.damionew
springclouddemo1
0.0.1-SNAPSHOT
jar
springclouddemo1
Demo project for Spring Boot
org.springframework.boot
spring-boot-starter-parent
1.3.7.RELEASE
UTF-8
UTF-8
1.8
org.springframework.boot
spring-boot-starter-web
org.springframework.boot
spring-boot-starter-actuator
org.springframework.boot
spring-boot-starter-test
test
org.springframework.cloud
spring-cloud-starter-eureka-server
org.springframework.cloud
spring-cloud-dependencies
Brixton.SR5
pom
import
org.springframework.boot
spring-boot-maven-plugin
spring-snapshots
Spring Snapshots
https://repo.spring.io/snapshot
true
spring-milestones
Spring Milestones
https://repo.spring.io/milestone
false
spring-snapshots
Spring Snapshots
https://repo.spring.io/snapshot
true
spring-milestones
Spring Milestones
https://repo.spring.io/milestone
false
5、终于学了怎么写单元测试：Springclouddemo1ApplicationTests.java
package com.demo;
import static org.hamcrest.CoreMatchers.equalTo;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.SpringApplicationConfiguration;
import org.springframework.http.MediaType;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.test.context.web.WebAppConfiguration;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.test.web.servlet.request.MockMvcRequestBuilders;
import org.springframework.test.web.servlet.setup.MockMvcBuilders;
import com.demo.web.HelloController;
@RunWith(SpringJUnit4ClassRunner.class) //引入Spring对JUnit4的支持
@SpringApplicationConfiguration(classes=Springclouddemo1Application.class) //指定SpringBoot的启动类
@WebAppConfiguration //开启Web应用的配置，用于模拟SevletContext
public class Springclouddemo1ApplicationTests {
private MockMvc mvc; //MockMvc对象，用于模拟调用Controller的接口发起请求，在@test定义的hello测试用例中
//perform函数执行一次请求调用,accept用于执行接收的数据类型，andExpect用于判断接口返回的期望值
@Before //Junit中定义在测试用例@Test内容执行前预加载的内容，这里用来初始化对HelloController的模拟
public void setUp() throws Exception {
mvc = MockMvcBuilders.standaloneSetup(new HelloController()).build();
}
@Test
public void hello() throws Exception {
mvc.perform(MockMvcRequestBuilders.get("/hello").accept(MediaType.APPLICATION_JSON))
.andExpect(status().isOk())
.andExpect(content().string(equalTo("Hello Spring Could!")));
}
}这样首先是创建好了一个SpringBoot项目，启动输入：http://localhost:8888/hello
页面输出：Hello Spring Cloud!
当然，因为现在已经通过@EnableDiscoveryClient注册为Eureka客户端，所以会报错。
二、创建一个eureka-server作为服务注册中心
1、创建启动类：EurekaServerApplication.java
package com.demo;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;
@EnableEurekaServer //该注解启动一个服务注册中心提供给其他应用进行对话
@SpringBootApplication
public class EurekaServerApplication {
public static void main(String[] args) {
new SpringApplicationBuilder(EurekaServerApplication.class).web(true).run(args);
}
}
2、配置application.properties文件
server.port=1111
eureka.instance.hostname=localhost
# 由于该应用为注册中心，所以设置为false，代表不向注册中心注册自己
eureka.client.register-with-eureka=false
# 由于注册中心的职责就是维护服务实例，它并不需要去检索服务，所以也设置为false
eureka.client.fetch-registry=false
eureka.client.serviceUrl.defaultZone=http://${eureka.instance.hostname}:${server.port}/eureka/3、pom.xml（同样使用1.3.7）
4.0.0
com.damionew
eureka-server
0.0.1-SNAPSHOT
jar
eureka-server
Demo project for Spring Boot
org.springframework.boot
spring-boot-starter-parent
1.3.7.RELEASE
UTF-8
UTF-8
1.8
org.springframework.cloud
spring-cloud-starter-eureka-server
org.springframework.cloud
spring-cloud-dependencies
Brixton.SR5
pom
import
org.springframework.boot
spring-boot-maven-plugin
spring-snapshots
Spring Snapshots
https://repo.spring.io/snapshot
true
spring-milestones
Spring Milestones
https://repo.spring.io/milestone
false
spring-snapshots
Spring Snapshots
https://repo.spring.io/snapshot
true
spring-milestones
Spring Milestones
https://repo.spring.io/milestone
false
此时启动以上两个项目，进入localhost:1111/会出现Eureka页面，此时有一个服务为HELLO-SERVICE
三：创建服务消费者ribbon-consumer
1、启动类RibbonConsumerApplication.java
package com.demo;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.web.client.RestTemplate;
@EnableDiscoveryClient //注册为Eureka客户端应用，以获取服务发现能力
@SpringBootApplication
public class RibbonConsumerApplication {
@Bean
@LoadBalanced //开启客户端的负载均衡
RestTemplate restTemplate() {
return new RestTemplate();
}
public static void main(String[] args) {
SpringApplication.run(RibbonConsumerApplication.class, args);
}
}
2、ConsumerController控制器
package com.demo.controller;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;
@RestController
public class ConsumeController {
/**
* 创建ConsumeController类并实现/ribbon-consumer接口，
* 在该接口中，通过启动类创建的RestTemplate来实现对HELLO-SERVICE服务提供的/hello接口进行调用
* 访问地址为服务名HELLO-SERVICE而不是具体地址，在服务治理框架中，这是非常重要的特性，也符合对服务治理的解释
*/
@Autowired
RestTemplate restTemplate;
@RequestMapping("/ribbon-consumer")
public String helloConsumer() {
return restTemplate.getForEntity("http://HELLO-SERVICE/hello", String.class).getBody();
}
}
3、application.properties配置
spring.application.name=ribbon-consumer
server.port=9000
eureka.client.serviceUrl.defaultZone=http://localhost:1111/eureka/4、pom.xml
4.0.0
com.damionew
ribbon-consumer
0.0.1-SNAPSHOT
jar
ribbon-consumer
Demo project for Spring Boot
org.springframework.boot
spring-boot-starter-parent
1.3.7.RELEASE
UTF-8
UTF-8
1.8
Edgware.BUILD-SNAPSHOT
org.springframework.cloud
spring-cloud-starter-eureka
org.springframework.cloud
spring-cloud-starter-ribbon
org.springframework.boot
spring-boot-starter-test
test
org.springframework.cloud
spring-cloud-dependencies
Brixton.SR5
pom
import
org.springframework.boot
spring-boot-maven-plugin
spring-snapshots
Spring Snapshots
https://repo.spring.io/snapshot
true
spring-milestones
Spring Milestones
https://repo.spring.io/milestone
false
spring-snapshots
Spring Snapshots
https://repo.spring.io/snapshot
true
spring-milestones
Spring Milestones
https://repo.spring.io/milestone
false
此时，启动三个项目，进入http://localhost:1111/结果如下：
拥有了两个服务，此时通过http://localhost:9000/ribbon-consumer，即消费者请求，可完成HELLO-SERVICE服务的/hello请求，同样输出Hello Spring Could!