## 服务消费者 consumer
创建maven工程，pom.xml
```java
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
<version>2.0.2.RELEASE</version>
</dependency>
</dependencies>
```
创建配置文件，application.yml
```java
server:
port: 8020
spring:
application:
name: consumer
eureka:
client:
service-url:
defaultZone: http://localhost:8761/eureka/
instance:
prefer-ip-address: true
```
创建启动类
```java
package com.shuang;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class ConsumerApplication {
public static void main(String[] args) {
SpringApplication.run(ConsumerApplication.class,args);
}
@Bean
public RestTemplate restTemplate(){
return new RestTemplate();
}
}
```
Handler
```java
package com.shuang.controller;
import com.shuang.entity.Student;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.client.RestTemplate;
import java.util.Collection;
@RestController
@RequestMapping("/consumer")
public class ConsumerHandler {
@Autowired
private RestTemplate restTemplate;
@GetMapping("/findAll")
public Collection<Student> findAll(){
return restTemplate.getForEntity("http://localhost:8010/student/findAll",Collection.class).getBody();
}
@GetMapping("/findAll2")
public Collection<Student> findAll2(){
return restTemplate.getForObject("http://localhost:8010/student/findAll",Collection.class);
}
@GetMapping("/findById/{id}")
public Student findById(@PathVariable("id") long id){
return restTemplate.getForEntity("http://localhost:8010/student/findById/{id}",Student.class,id).getBody();
}
@GetMapping("/findById2/{id}")
public Student findById2(@PathVariable("id") long id){
return restTemplate.getForObject("http://localhost:8010/student/findById/{id}",Student.class,id);
}
@PostMapping("save")
public void save(@RequestBody Student student){
restTemplate.postForEntity("http://localhost:8010/student/save",student,null).getBody();
}
@PostMapping("/save2")
public void save2(@RequestBody Student student){
restTemplate.postForObject("http://localhost:8010/student/save",student,null);
}
@PutMapping("/update")
public void update(@RequestBody Student student){
restTemplate.put("http://localhost:8010/student/update",student);
}
@DeleteMapping("/deleteById/{id}")
public void deleteById(@PathVariable("id") long id){
restTemplate.delete("http://localhost:8010/student/deleteById/{id}",id);
}
}
```
## 服务网关：
Spring Cloud 集成了 Zuul组件，实现服务网关
Zuul是Netflix提供的一个开源的API网关服务器，是客户端和网站后端所有请求
的中间层，对外开放一个API，将所有请求导入统一的入口，屏蔽了服务端的具体
实现逻辑，Zuul可以实现反向代理的功能，在网关内部实现动态路由、身份认证、
IP过滤、数据监控等。
创建Maven工程，pom.xml
```java
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
<version>2.0.2.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-zuul</artifactId>
<version>2.0.2.RELEASE</version>
</dependency>
</dependencies>
```
创建配置文件。application.yml
```java
server:
port: 8030
spring:
application:
name: gateway
eureka:
client:
service-url:
defaultZone: http://localhost:8761/eureka/
zuul:
routes:
provider: /p/**
```
属性说明：
zuul.routers.provider：给服务提供者provider设置映射
创建启动类
```java
package com.shuang;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.cloud.netflix.zuul.EnableZuulProxy;
@EnableZuulProxy
@EnableAutoConfiguration
public class ZuulApplication {
public static void main(String[] args) {
SpringApplication.run(ZuulApplication.class,args);
}
}
```
注解说明：
EnableZuulProxy：包含了EnableZuulServer，设置该类是网关的启动类。
EnableAutoConfiguretion：可以帮助Spring Boot应用将所有符合条件的
Configuration配置加载到当前Spring Boot创建并使用的IOC容器中。
Zuul自带了负载均衡功能，修改provider的代码
```java
package com.shuang.controller;
import com.shuang.entity.Student;
import com.shuang.repository.StudentRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.*;
import java.util.Collection;
@RestController
@RequestMapping("/student")
public class StudentHandler {
@Autowired
private StudentRepository studentRepository;
@Value("${server.port}")
private String port;
@GetMapping("/findAll")
public Collection<Student> findAll(){
return studentRepository.findAll();
}
@GetMapping("/findById/{id}")
public Student findById(@PathVariable("id") long id){
return studentRepository.findById(id);
}
@PostMapping("/save")
public void save(@RequestBody Student student){
studentRepository.saveOrUpdate(student);
}
@PutMapping("/update")
public void update(@RequestBody Student student){
studentRepository.saveOrUpdate(student);
}
@DeleteMapping("/deleteById/{id}")
public void deleteById(@PathVariable("id") long id){
studentRepository.deleteById(id);
}
@GetMapping("/index")
public String index(){
return "当前的端口: "+this.port;
}
}
```
启动eurekaclient的启动类。修改端口，增加另外一个启动类，启动（相当于两个相同服务提供者）
在Zuul中访问：两个服务提供者轮流提供服务
