一、Consul的简单介绍
Consul是一套开源的分布式服务发现和配置管理系统，由HasiCorp公司用go语言开发的。提供了微服务系统中服务助理、配置中心、控制总线等功能，这些功能中的每一个都可以根据需要单独使用，也可以一起使用以构造全方位的服务网络，总之，Consul提供了完整的服务网格解决方案。
二、Consul的优点
它具有很多优点，包括：基于raft协议，比较简洁；支持健康检查，同时支持Http和DNS协议，支持跨数据中心WAN集群，提供图形界面，跨平台；支持linux、mac、windows
三、Consul的下载和启动
（1）打开consul官网
https://www.consul.io/downloads
（2）点击Download
(3)解压得到 consul.exe 文件，在 consul.exe 文件cmd 命令窗口执行：consul agent -dev进行启动
consul 自带 UI 界面，打开网址：http://localhost:8500 ，可以看到当前注册的服务界面。
四、Consul的快速使用-服务提供者
（1）创建springboot工程provider8006，引入下面依赖
<!--SpringCloud consul-server -->
<dependencies><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-consul-discovery</artifactId></dependency><!-- SpringBoot整合Web组件 --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-actuator</artifactId></dependency></dependencies><dependencyManagement><dependencies><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-dependencies</artifactId><version>Hoxton.SR10</version><type>pom</type><scope>import</scope></dependency></dependencies></dependencyManagement><!--在本地仓库找不到就到官网去找--><repositories><repository><id>spring-milestones</id><name>Spring Milestones</name><url>https://repo.spring.io/libs-milestone</url><snapshots><enabled>false</enabled></snapshots></repository></repositories>
（2)在配置文件配置下面信息
###consul服务端口号
server.port=8006
spring.application.name=consul-provider-payment
####consul注册中心地址
spring.cloud.consul.host=localhost
spring.cloud.consul.port=8500
spring.cloud.consul.discovery.service-name=${spring.application.name}
#hostname: 127.0.0.1
（3）在主启动类，添加@EnableDiscoveryClient
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;@SpringBootApplication
@EnableDiscoveryClient
public class PaymentMain8006
{public static void main(String[] args) {SpringApplication.run(PaymentMain8006.class, args);}
}
（4）业务类Controller
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.UUID;@RestController
@Slf4j
public class PaymentController
{@Value("${server.port}")private String serverPort;@RequestMapping(value = "/payment/consul")public String paymentConsul(){return "springcloud with consul: "+serverPort+"\t "+ UUID.randomUUID().toString();}
}
（5)验证测试
http://localhost:8006/payment/consul
http://localhost:8500 - 会显示provider8006
五、Consul的快速使用-.服务消费者
（1）创建springboot工程order80 - cloud-consumerconsul-order80，添加下面依赖
<dependencies><!--SpringCloud consul-server --><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-consul-discovery</artifactId></dependency><!-- SpringBoot整合Web组件 --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-actuator</artifactId></dependency>
</dependencies><dependencyManagement><dependencies><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-dependencies</artifactId><version>Hoxton.SR10</version><type>pom</type><scope>import</scope></dependency></dependencies></dependencyManagement><!--在本地仓库找不到就到官网去找--><repositories><repository><id>spring-milestones</id><name>Spring Milestones</name><url>https://repo.spring.io/libs-milestone</url><snapshots><enabled>false</enabled></snapshots></repository></repositories>
（2）在配置文件添加下面信息
###consul服务端口号
server.port=80
spring.application.name=cloud-consumer-order
####consul注册中心地址
spring.cloud.consul.host=localhost
spring.cloud.consul.port=8500
spring.cloud.consul.discovery.service-name=${spring.application.name}
#hostname: 127.0.0.1
（3）在主启动类添加@EnableDiscoveryClient
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;@SpringBootApplication
@EnableDiscoveryClient //该注解用于向使用consul或者zookeeper作为注册中心时注册服务
public class OrderConsulMain80
{public static void main(String[] args) {SpringApplication.run(OrderConsulMain80.class, args);}
}
（4）配置Bean
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.client.RestTemplate;/***/
@Configuration
public class ApplicationContextConfig
{@Bean@LoadBalancedpublic RestTemplate getRestTemplate(){return new RestTemplate();}
}
(5)业务类
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;import javax.annotation.Resource;@RestController
@Slf4j
public class OrderConsulController
{public static final String INVOKE_URL = "http://consul-provider-payment";@Resourceprivate RestTemplate restTemplate;@GetMapping(value = "/consumer/payment/consul")public String paymentInfo(){String result = restTemplate.getForObject(INVOKE_URL+"/payment/consul",String.class);return result;}
}
（6)验证测试
运行启动consul，cloud-providerconsul-payment8006，cloud-consumerconsul-order80
http://localhost:8500/ 主页会显示出consul，cloud-providerconsul-payment8006，cloud-consumerconsul-order80三服务。
（7)访问测试地址 - http://localhost/consumer/payment/consul
