记一次使用Consul进行服务注册和服务发现

服务注册与发现

因为Consul对.net core的支撑和对Ocelot的高度兼容性，所以，.net core使用的服务注册与发现的组件大多数使用的Consul。

首先。我有一个测试服务A。这个服务会进行服务注册。用于对外提供服务。

服务A :

首先，Nuget安装Consul

添加一个扩展类ConsulExtensions 

public static class ConsulExtensions
    {
        public static IApplicationBuilder RegisterConsul(this IApplicationBuilder app, IConfiguration configuration)//, IHostApplicationLifetime lifetime)
        {
            var consulClient = new ConsulClient(c =>
            {
                c.Address = new Uri(configuration["ConsulSetting:ConsulAddress"]);
            });

            var registration = new AgentServiceRegistration()
            {
                ID = Guid.NewGuid().ToString(),//服务实例唯一标识
                Name = configuration["ConsulSetting:ServiceName"],//服务名
                Address = configuration["ConsulSetting:ServiceIP"], //服务IP
                Port = int.Parse(configuration["ConsulSetting:ServicePort"]),//服务端口 因为要运行多个实例，端口不能在appsettings.json里配置，在docker容器运行时传入
                Check = 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
                    HTTP = $"http://{configuration["ConsulSetting:ServiceIP"]}:{configuration["ConsulSetting:ServicePort"]}{configuration["ConsulSetting:ServiceHealthCheck"]}",//健康检查地址
                    Timeout = TimeSpan.FromSeconds(5)//超时时间
                }
            };

            //服务注册
            consulClient.Agent.ServiceRegister(registration).Wait();

            ////应用程序终止时，手动取消注册
            //lifetime.ApplicationStopping.Register(() =>
            //{
            //    consulClient.Agent.ServiceDeregister(registration.ID).Wait();
            //});

            return app;
        }
    }

　　在Starup里面注册Consul服务

app.RegisterConsul(context.GetConfiguration());

在appsettings.json里面添加配置

"ConsulSetting": {
    "ServiceName": "TestService",
    "ServiceIP": "localhost",
    "ServiceHealthCheck": "/healthcheck",
    "ServicePort": "5000",
    "ConsulAddress": "http://localhost:8500"
  }

启动服务，在Consul里面就能看见这个服务已经注册进去了

现在再开始进入测试服务B，这个服务用于服务发现，并调用测试服务A的接口。

首先，还是先安装Consul组件。然后创建一个IConsulTestAppService，并用ConsulTestAppService实现它。

public class ConsulTestAppService : IConsulTestAppService
    {
        private readonly IConfiguration _configuration;
        public ConsulTestAppService(IConfiguration configuration)
        {
            _configuration = configuration;
        }
        public async Task<string> GetAsync()
        {
            var consulClient = new ConsulClient(c =>
            {
                //consul地址
                c.Address = new Uri(_configuration["ConsulSetting:ConsulAddress"]);
            });

            var services = consulClient.Health.Service("TestService", null, true, null).Result.Response;//健康的服务

            string[] serviceUrls = services.Select(p => $"http://{p.Service.Address + ":" + p.Service.Port}").ToArray();//订单服务地址列表

            if (!serviceUrls.Any())
            {
                return await Task.FromResult("【TestService】服务列表为空");
            }

            //每次随机访问一个服务实例
            var Client = new RestClient(serviceUrls[new Random().Next(0, serviceUrls.Length)]);
            var request = new RestRequest("/api/test/GetOne", Method.GET);

            var response = await Client.ExecuteAsync(request);
            return response.Content;
        }
    }

我这里使用RestSharp来进行Http请求。

访问服务，TestService已经正常响应数据。