.net core使用Consul

参考文章：
https://www.cnblogs.com/edisonchou/p/9124985.html

上面的文章已经写的非常好了，我在这就再简单的写一下，参考文章里的代码有个地方需要注意IApplicationLifetime这个需要替换一下 那个是老版本的.net core用的，替换成IHostApplicationLifetime同样是在Microsoft.Extensions.Hosting里

Consul是Go语言写的，在.net core的web程序里面主要是用来做服务的注册和发现

首先下载Consul
https://www.consul.io/downloads

然后解压直接用

这里是dev环境 更多具体的使用再百度
按回车 然后输入一下网址
http://localhost:8500

然后开始整代码
新建一个扩展方法：

using Consul;
using Microsoft.AspNetCore.Builder;
using Microsoft.Extensions.Hosting;
using System;

namespace Hotel.Web.API.Extension
{
    public static class AppBuilderExtensions
    {
        public static IApplicationBuilder RegisterConsul(this IApplicationBuilder app, IHostApplicationLifetime lifetime, ServiceEntity serviceEntity)
        {
            var consulClient = new ConsulClient(x => x.Address = new Uri($"http://{serviceEntity.ConsulIP}:{serviceEntity.ConsulPort}"));//请求注册的 Consul 地址
            var httpCheck = new AgentServiceCheck()
            {
                DeregisterCriticalServiceAfter = TimeSpan.FromSeconds(5),//服务启动多久后注册
                Interval = TimeSpan.FromSeconds(10),//健康检查时间间隔，或者称为心跳间隔
                HTTP = $"http://{serviceEntity.IP}:{serviceEntity.Port}/api/Health",//健康检查地址
                Timeout = TimeSpan.FromSeconds(5)
            };

            // Register service with consul
            var registration = new AgentServiceRegistration()
            {
                Checks = new[] { httpCheck },
                ID = Guid.NewGuid().ToString(),
                Name = serviceEntity.ServiceName,
                Address = serviceEntity.IP,
                Port = serviceEntity.Port,
                Tags = new[] { $"urlprefix-/{serviceEntity.ServiceName}" }//添加 urlprefix-/servicename 格式的 tag 标签，以便 Fabio 识别
            };

            consulClient.Agent.ServiceRegister(registration).Wait();//服务启动时注册，内部实现其实就是使用 Consul API 进行注册（HttpClient发起）
            lifetime.ApplicationStopping.Register(() =>
            {
                consulClient.Agent.ServiceDeregister(registration.ID).Wait();//服务停止时取消注册
            });

            return app;
        }

    }
}

加个类

    public class ServiceEntity
    {
        public string IP { get; set; }
        public int Port { get; set; }
        public string ServiceName { get; set; }
        public string ConsulIP { get; set; }
        public int ConsulPort { get; set; }
    }

配置文件里添加如下配置 这里加在appSetting.json里了

  "Consul": {
    "IP": "localhost",
    "Port": 8002,
    "ServiceName": "hotel_api",
    "ConsulIP": "localhost",
    "ConsulPort": 8500
  }

然后在Startup类里的Configure方法里添加

            // register this service
            ServiceEntity serviceEntity = new ServiceEntity
            {
                IP = "localhost",
                Port = Convert.ToInt32(Configuration["Consul:Port"]),
                ServiceName = Configuration["Consul:ServiceName"],
                ConsulIP = Configuration["Consul:ConsulIP"],
                ConsulPort = Convert.ToInt32(Configuration["Consul:ConsulPort"])
            };
            app.RegisterConsul(lifetime, serviceEntity);

注意 lifetime 这个需要在Configure方法的参数里加个参数Microsoft.Extensions.Hosting.IHostApplicationLifetime lifetime

现在就可以了 运行程序

完事