Consul之：服務注冊與發現

本文轉載自查看原文 2018-09-17 14:28 2964 springcloud/ consul/ micro-service

一、服務的管理（注冊與發現）有三種方式：

1：通過配置文件的方式靜態注冊
2：通過HTTP API接口來動態注冊（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）實現服務的注冊和發現（Java非spring boot，cloud項目）

1.1、通過配置文件的方式靜態注冊

1.1.1、創建文件夾/etc/consul.d，

說明：.d表示一系列配置文件的存放目錄（directory）

1.1.2、創建服務並寫入上述文件夾中的一個文件

說明：

一個服務我們會配置為json格式：比如上述的單引號之間的形式
一個服務會寫在一個json文件中

注意：如果上述文件夾沒有權限進行操作，先改變文件夾權限，

我在window上，演示：

1.1.3、先啟動consul進程，帶上config-dir參數

切換屏幕-->

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

說明：

根據-config-dir指定根據服務注冊的目錄中的文件來啟動服務。

1.2：通過HTTP API接口來動態注冊

直接調用/v1/agent/service/register接口注冊即可，需要注意的是：http method為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，這種方式，和上面的注冊方式有一點不一樣，body的參數，是上面service的值，這點需要注意。

結果：

1.3：使用Consul client或Consul api實現服務的注冊和發現（Java非spring boot，spring cloud項目）

1.3.1、使用Consul Client

首先加入consul client的依賴

<dependency>  
    <groupId>com.orbitz.consul</groupId>  
    <artifactId>consul-client</artifactId>  
    <version>0.15.1</version>  
</dependency>

主類：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();  
  
    /** 
     * 服務注冊 
     */  
    public static void serviceRegister() {  
        AgentClient agent = consul.agentClient();  
          
        //健康檢測  
        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());  
    }  
      
    /** 
     * 服務獲取 
     */  
    public static void serviceGet() {  
        HealthClient client = consul.healthClient();  
        String name = "consul-server";  
        //獲取所有服務  
        System.out.println(client.getAllServiceInstances(name).getResponse().size());  
          
        //獲取所有正常的服務（健康檢測通過的）  
        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);
    }  
}

上面的注冊后，看consul控制台如下：

1.3.2、使用Consul API

當然了，還可以使用如下consul api

        <dependency>
            <groupId>com.ecwid.consul</groupId>
            <artifactId>consul-api</artifactId>
            <version>1.2.2</version>
        </dependency>

主類：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);  
         //獲取所有服務  
         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);
    }  
}

啟動時的日志片段：

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 使用的就是第二種consul api。