spring cloud:搭建基于consul的服务提供者集群(spring cloud hoxton sr8 / spring boot 2.3.4)

一，搭建基于consul的服务提供者集群

1,consul集群，共3个实例：

2, 服务提供者集群:共2个实例：

3，服务消费者：一个实例即可

4,consul集群的搭建,请参考:

https://www.cnblogs.com/architectforest/p/13735545.html

5，演示例子实现生产环境中需要的高可用：

             consul server集群和服务提供者集群

说明：刘宏缔的架构森林是一个专注架构的博客，地址：https://www.cnblogs.com/architectforest

         对应的源码可以访问这里获取： https://github.com/liuhongdi/

说明：作者:刘宏缔 邮箱: 371125307@qq.com

二，演示项目的相关信息:

1,两个项目的地址:

  服务提供者:

https://github.com/liuhongdi/cloudconsul

  服务消费者:

https://github.com/liuhongdi/consulconsumer

2,项目的功能说明

           演示了基于consul实现的服务提供者和消费者，

                            基于consul集群和消费者集群

3，服务提供者项目的结构：如图

4，服务消费者项目的结构：如图

 

三，服务提供者项目的配置文件说明

 1，pom.xml

        <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>

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-consul-discovery</artifactId>
        </dependency>

 2,application.properties

spring.application.name=provider1
server.port=8080
#
spring.cloud.consul.host=127.0.0.1
spring.cloud.consul.port=8500
spring.cloud.consul.discovery.service-name=lhdprovider
spring.cloud.consul.discovery.prefer-ip-address=true
spring.cloud.consul.discovery.instance-id=${spring.application.name}:${spring.cloud.client.ip-address}
provider.name = p1

3,application-provider2.properties

spring.application.name=provider2
server.port=8080
#
spring.cloud.consul.host=127.0.0.1
spring.cloud.consul.port=8500
spring.cloud.consul.discovery.service-name=lhdprovider
spring.cloud.consul.discovery.prefer-ip-address=true
spring.cloud.consul.discovery.instance-id=${spring.application.name}:${spring.cloud.client.ip-address}
provider.name = p2

说明：spring.cloud.consul.discovery.prefer-ip-address=true：

这个配置项的作用是consul中提供的服务名称是ip和port,

这样消费者可以直接访问服务提供者，否则的话，

需要在运行服务消费者的机器上配置实例名称和ip的对应到 /etc/hosts当中才行

四，服务提供者项目的java代码说明

1,DemoApplication.java

@EnableDiscoveryClient
@SpringBootApplication
public class DemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }

}

2,HomeController.java

@RestController
@RequestMapping("/home")
public class HomeController {

    @Resource
    private DiscoveryClient discoveryClient;

    @Value("${provider.name}")
    private String name;

    @Value("${server.port}")
    private String port;

    // list services
    @GetMapping("/serviceslist")
    public Object serviceslist() {
        return discoveryClient.getServices();
    }

    // list instances in a service id
    @GetMapping("/instanceslist")
    public Object instanceslist() {
        return discoveryClient.getInstances("consul");
    }

    //test api
    @GetMapping("/hello")
    public String hello() {
        String ip = "";
        try {
        Enumeration<NetworkInterface> interfaces = NetworkInterface.getNetworkInterfaces();
        while (interfaces.hasMoreElements()) {
            NetworkInterface current = interfaces.nextElement();
            if (!current.isUp() || current.isLoopback() || current.isVirtual()) continue;
            Enumeration<InetAddress> addresses = current.getInetAddresses();
            while (addresses.hasMoreElements()) {
                InetAddress addr = addresses.nextElement();
                if (addr.isLoopbackAddress()) continue;
                ip = addr.getHostAddress();
            }
        }
        } catch (SocketException e) {
            e.printStackTrace();
        }
        System.out.println("ip:"+ip);
        //return discoveryClient.getInstances("consul");
        String res = "ip:"+ip+";name:"+name+";port:"+port;
        return res;
    }
}

五，服务消费者项目的配置文件说明

1,pom.xml

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-consul-discovery</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>

2,application.properties

spring.application.name=lhdconsumer
spring.cloud.consul.host=localhost
spring.cloud.consul.port=8500
spring.cloud.consul.discovery.register=false
server.port=8081

六，服务消费者项目的java代码说明

1,DemoApplication.java

@SpringBootApplication
@EnableDiscoveryClient
@EnableFeignClients
public class DemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }

}

2,HiService.java

@Service
public class HiService {

    @Resource
    HomeFeignClient homeFeignClient;

    public String sayHi(String name){
        return  homeFeignClient.sayHifromClient();
    }
}

3,HomeFeignClient.java

@FeignClient(value="lhdprovider")
public interface HomeFeignClient {
     @GetMapping(value="/home/hello")
     String sayHifromClient();
}

4,HomeController.java

@RestController
@RequestMapping("/home")
public class HomeController {

    @Resource
    HiService hiService;

    @GetMapping("/hi")
    public String sayHi(){
        return hiService.sayHi();
    }
}

七，搭建服务提供者集群

provider1上：

1,启动consul

[root@provider1 /]# nohup /usr/local/soft/consul agent -data-dir=/data/consul/data -node=provider1 -bind=172.17.0.5 -datacenter=dc1 -client=0.0.0.0 -join=172.17.0.2 > /dev/null 2>&1 & 

2,启动服务:

[root@provider1 /]# /usr/local/soft/jdk-13/bin/java -jar /usr/local/soft/demo-0.0.1-SNAPSHOT.jar

provider2上：

1，启动consul

[root@provider2 /]# nohup /usr/local/soft/consul agent -data-dir=/data/consul/data -node=provider2 -bind=172.17.0.6 -datacenter=dc1 -client=0.0.0.0 -join=172.17.0.2 > /dev/null 2>&1 &  
[1] 206

2,启动服务:

[root@provider2 /]# /usr/local/soft/jdk-13/bin/java -jar /usr/local/soft/demo-0.0.1-SNAPSHOT.jar --spring.profiles.active=provider2

八，测试效果

1,服务启动后，查看服务提供的情况:

访问:

http://172.17.0.5:8080/home/hello

返回:

ip:172.17.0.5;name:p1;port:8080

访问：

http://172.17.0.6:8080/home/hello

返回:

ip:172.17.0.6;name:p2;port:8080

2,测试服务消费者:访问:

http://127.0.0.1:8081/home/hi

返回:

ip:172.17.0.5;name:p1;port:8080

刷新后返回:

ip:172.17.0.6;name:p2;port:8080

3,测试高可用：关掉服务:

在provider2上，把服务停掉:

直接ctrl-c关掉或者kill也可

ip:172.17.0.6
ip:172.17.0.6
^C2020-10-06 08:41:30.727  INFO 379 --- [extShutdownHook] o.s.s.c.ThreadPoolTaskScheduler          : Shutting down ExecutorService 'catalogWatchTaskScheduler'
2020-10-06 08:41:30.738  INFO 379 --- [extShutdownHook] o.s.c.c.s.ConsulServiceRegistry          : Deregistering service with consul: provider2-172-17-0-6
2020-10-06 08:41:30.780  INFO 379 --- [extShutdownHook] o.s.s.concurrent.ThreadPoolTaskExecutor  : Shutting down ExecutorService 'applicationTaskExecutor'

然后查看consul的web ui：

 可以看到lhdprovider中只剩下了一个实例：

访问服务消费者:

http://127.0.0.1:8081/home/hi

返回:

ip:172.17.0.5;name:p1;port:8080

反复刷新后返回结果中也没有provider2的返回，只有p1的返回，
说明高可用有效

4,测试高可用：关掉consul的agent

把上面所掉的provider2的服务再次启动

这次我们关掉provider1上的consul client

[root@provider1 /]# ps auxfww
USER        PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root        495  0.5  0.0  12028  3012 pts/2    Ss   08:48   0:00 /bin/bash
root        508  0.0  0.0  43964  3084 pts/2    R+   08:48   0:00  \_ ps auxfww
root        200  0.0  0.0  12128   180 pts/1    Ss   01:16   0:00 /bin/bash
root        239  0.4  0.5 784952 23788 pts/1    Sl   07:09   0:24  \_ /usr/local/soft/consul agent -data-dir=/data/consul/data -node=provider1 -bind=172.17.0.5 -datacenter=dc1 -client=0.0.0.0 -join=172.17.0.2
root        453  0.8  2.2 3619488 91824 pts/1   Sl+  07:42   0:34  \_ /usr/local/soft/jdk-13/bin/java -jar /usr/local/soft/demo-0.0.1-SNAPSHOT.jar
root          1  0.0  0.0  93860   376 ?        Ss   01:15   0:00 /usr/sbin/init
root         25  0.0  0.0  91304  1176 ?        Ss   01:15   0:00 /usr/lib/systemd/systemd-journald
root         33  0.0  0.0  88832    76 ?        Ss   01:15   0:00 /usr/lib/systemd/systemd-udevd
dbus         66  0.0  0.0  52812     0 ?        Ss   01:15   0:00 /usr/bin/dbus-daemon --system --address=systemd: --nofork --nopidfile --systemd-activation --syslog-only
[root@provider1 /]# kill 239
[root@provider1 /]# kill 239
[root@provider1 /]# kill 239
bash: kill: (239) - No such process

查看consul的web ui,只剩下了provider2

访问消费者：

http://127.0.0.1:8081/home/hi

只返回:

ip:172.17.0.6;name:p2;port:8080

5，测试高可用：关掉consul集群中的一个:

[root@consul1 /]# /usr/local/soft/consul leave
Graceful leave complete
[1]+  Done                    nohup /usr/local/soft/consul agent -server -bind=172.17.0.2 -client=0.0.0.0 -bootstrap-expect=2 -data-dir=/data/consul/da -node=server-2 > /dev/null 2>&1

查看consul web ui,只剩下了两个实例

进入查看:

 测试服务消费者：访问:

http://127.0.0.1:8081/home/hi

可以正常访问

九，查看spring boot版本:

  .   ____          _            __ _ _
 /\ / ___'_ __ _ _(_)_ __  __ _    
( ( )\___ | '_ | '_| | '_ / _` |    
 \/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v2.3.4.RELEASE)