Consul之：服务注册与发现

一、服务的管理（注册与发现）有三种方式：

1：通过配置文件的方式静态注册
2：通过HTTP API接口来动态注册（spring cloud使用方式，spring cloud中使用的是consul api）
3：使用consul client或consul api（程序）实现服务的注册和发现（Java非spring boot，cloud项目）

1.1、通过配置文件的方式静态注册

1.1.1、创建文件夹/etc/consul.d，

说明：.d表示一系列配置文件的存放目录（directory）

1.1.2、创建服务并写入上述文件夹中的一个文件

说明：

一个服务我们会配置为json格式：比如上述的单引号之间的形式
一个服务会写在一个json文件中

注意：如果上述文件夹没有权限进行操作，先改变文件夹权限，

我在window上，演示：

1.1.3、先启动consul进程，带上config-dir参数

切换屏幕-->

window上：D:\soft\worksoft\consul_1.0.6_windows_amd64>consul agent -dev -config-dir etc/consul.d/

说明：

根据-config-dir指定根据服务注册的目录中的文件来启动服务。

1.2：通过HTTP API接口来动态注册

直接调用/v1/agent/service/register接口注册即可，需要注意的是：http method为PUT提交方式

如：

curl -X PUT -d '{"id": "jetty","name": "jetty","address": "192.168.1.200","port": 8080,"tags": ["dev"],"checks": [{"http": "http://192.168.1.104:9020/health","interval": "5s"}]}' http://192.168.1.100:8500/v1/agent/service/register

注意，这种方式，和上面的注册方式有一点不一样，body的参数，是上面service的值，这点需要注意。

结果：

1.3：使用Consul client或Consul api实现服务的注册和发现（Java非spring boot，spring cloud项目）

1.3.1、使用Consul Client

首先加入consul client的依赖

<dependency>

    <groupId>com.orbitz.consul</groupId>

    <artifactId>consul-client</artifactId>

    <version>0.15.1</version>

</dependency>

主类：ConsulClientDemo.java

package com.dxz.Consul_client;

import java.util.List;

import com.google.common.net.HostAndPort;

import com.orbitz.consul.AgentClient;

import com.orbitz.consul.Consul;

import com.orbitz.consul.HealthClient;

import com.orbitz.consul.model.agent.ImmutableRegCheck;

import com.orbitz.consul.model.agent.ImmutableRegistration;

import com.orbitz.consul.model.health.ServiceHealth;  

public class ConsulClientDemo {  

    static Consul consul = Consul.builder().withHostAndPort(HostAndPort.fromString("localhost:8500")).withPing(false).build();  

    /**

     * 服务注册

     */

    public static void serviceRegister() {

        AgentClient agent = consul.agentClient();  

        //健康检测

        ImmutableRegCheck check = ImmutableRegCheck.builder().http("http://localhost:9020/health").interval("5s").build();  

        ImmutableRegistration.Builder builder = ImmutableRegistration.builder();

        builder.id("consul-server3").name("consul-server").addTags("v1").address("localhost").port(8080).addChecks(check);  

        agent.register(builder.build());

    }  

    /**

     * 服务获取

     */

    public static void serviceGet() {

        HealthClient client = consul.healthClient();

        String name = "consul-server";

        //获取所有服务

        System.out.println(client.getAllServiceInstances(name).getResponse().size());  

        //获取所有正常的服务（健康检测通过的）

        List<ServiceHealth> responses = client.getHealthyServiceInstances(name).getResponse();

        for(ServiceHealth sh : responses ) {

            System.out.println(sh.getService());

        }

    }  

    public static void main(String[] args) {

        serviceRegister();

        serviceGet();

        System.exit(0);

    }

}

上面的注册后，看consul控制台如下：

1.3.2、使用Consul API

当然了，还可以使用如下consul api

        <dependency>

            <groupId>com.ecwid.consul</groupId>

            <artifactId>consul-api</artifactId>

            <version>1.2.2</version>

        </dependency>

主类：ConsulApiDemo.java

package com.dxz.Consul_client;

import java.util.List;

import java.util.Map;

import com.ecwid.consul.v1.ConsulClient;

import com.ecwid.consul.v1.ConsulRawClient;

import com.ecwid.consul.v1.agent.model.Service;

import com.ecwid.consul.v1.health.model.HealthService;  

public class ConsulApiDemo {  

    public static void serviceApiGet() {

         ConsulRawClient client = new ConsulRawClient("localhost", 8500);

         ConsulClient consul = new ConsulClient(client);

         //获取所有服务

         Map<String, Service> map = consul.getAgentServices().getValue();

         List<HealthService> list = consul.getHealthServices("consul-server", false, null).getValue();

         System.out.println(map.size()+"," +map);

         System.out.println("list" + list);

    }

    public static void main(String[] args) {

        serviceApiGet();

        System.exit(0);

    }

}

启动时的日志片段：

6,map={application=Service{id='application', service='application', tags=[], address='192.168.5.6', port=8080}, consul=Service{id='consul', service='consul', tags=[], address='', port=8300}, consul-client1=Service{id='consul-client1', service='consul-client', tags=[], address='DESKTOP-PPSFCNC', port=8501}, consul-server1=Service{id='consul-server1', service='consul-server', tags=[], address='DESKTOP-PPSFCNC', port=8503}, consul-server2=Service{id='consul-server2', service='consul-server', tags=[], address='DESKTOP-PPSFCNC', port=8504}, consul-server3=Service{id='consul-server3', service='consul-server', tags=[v1], address='localhost', port=8080}}

3,list=[HealthService{node=Node{node='DESKTOP-PPSFCNC', address='127.0.0.1'}, service=Service{id='consul-server1', service='consul-server', tags=[], address='DESKTOP-PPSFCNC', port=8503}, checks=[Node{node='DESKTOP-PPSFCNC', checkId='serfHealth', name='Serf Health Status', status=PASSING, notes='', output='Agent alive and reachable', serviceId='', serviceName=''}, Node{node='DESKTOP-PPSFCNC', checkId='service:consul-server1', name='Service 'consul-server' check', status=CRITICAL, notes='', output='parse http://DESKTOP-PPSFCNC:8503${management.contextPath}/health: invalid character "{" in host name', serviceId='consul-server1', serviceName='consul-server'}]}, HealthService{node=Node{node='DESKTOP-PPSFCNC', address='127.0.0.1'}, service=Service{id='consul-server2', service='consul-server', tags=[], address='DESKTOP-PPSFCNC', port=8504}, checks=[Node{node='DESKTOP-PPSFCNC', checkId='serfHealth', name='Serf Health Status', status=PASSING, notes='', output='Agent alive and reachable', serviceId='', serviceName=''}, Node{node='DESKTOP-PPSFCNC', checkId='service:consul-server2', name='Service 'consul-server' check', status=CRITICAL, notes='', output='parse http://DESKTOP-PPSFCNC:8504${management.contextPath}/health: invalid character "{" in host name', serviceId='consul-server2', serviceName='consul-server'}]}, HealthService{node=Node{node='DESKTOP-PPSFCNC', address='127.0.0.1'}, service=Service{id='consul-server3', service='consul-server', tags=[v1], address='localhost', port=8080}, checks=[Node{node='DESKTOP-PPSFCNC', checkId='serfHealth', name='Serf Health Status', status=PASSING, notes='', output='Agent alive and reachable', serviceId='', serviceName=''}, Node{node='DESKTOP-PPSFCNC', checkId='service:consul-server3', name='Service 'consul-server' check', status=CRITICAL, notes='', output='Get http://localhost:9020/health: dial tcp [::1]:9020: connectex: No connection could be made because the target machine actively refused it.', serviceId='consul-server3', serviceName='consul-server'}]}]

其中，spring cloud 使用的就是第二种consul api。