Install-Package Ocelot.Provider.Consul

services.AddOcelot().AddConsul();

{
  "Routes": [
    {
      "UseServiceDiscovery": true,
      "DownstreamPathTemplate": "/{url}",
      "DownstreamScheme": "http",
      "ServiceName": "MyService",
      "LoadBalancerOptions": {
        "Type": "RoundRobin"
      },
      "UpstreamPathTemplate": "/{url}",
      "UpstreamHttpMethod": [ "Get" ],
      "ReRoutesCaseSensitive": false
    }
  ],
  "GlobalConfiguration": {
    //服務(wù)發(fā)現(xiàn)配置
    "ServiceDiscoveryProvider": {
      //注冊(cè)中心Consul地址
      "Host": "192.168.113.128",
      //注冊(cè)中心Consul端口號(hào)
      "Port": 8500,
      "Type": "Consul",
      //以毫秒為單位，告訴Ocelot多久調(diào)用一次Consul來更改服務(wù)配置。
      "PollingInterval": 100,
      //如果你有在Consul上配置key/value，則在這里輸入配置key。
      "ConfigurationKey": "MyService_AB"
    }
  }
}

services.AddOcelot().AddConsul();

app.UseOcelot().Wait();

Install-Package Consul

public static class AppExtensions
{
    public static IServiceCollection AddConsulConfig(this IServiceCollection services, IConfiguration configuration)
    {
        services.AddSingleton<IConsulClient, ConsulClient>(p => new ConsulClient(consulConfig =>
        {
            var address = configuration.GetValue<string>("Consul:Host");
            consulConfig.Address = new Uri(address);
        }));
        return services;
    }
    public static IApplicationBuilder UseConsul(this IApplicationBuilder app, string host = null, string port = null)
    {
        //獲取consul客戶端實(shí)例
        var consulClient = app.ApplicationServices.GetRequiredService<IConsulClient>();
        var logger = app.ApplicationServices.GetRequiredService<ILoggerFactory>().CreateLogger("AppExtensions");
        var lifetime = app.ApplicationServices.GetRequiredService<IApplicationLifetime>();

        if (!(app.Properties["server.Features"] is FeatureCollection features)) return app;

        //var addresses = features.Get<IServerAddressesFeature>();
        //var address = addresses.Addresses.FirstOrDefault();
        //if (address == null)
        //{
        //    return app;
        //}

        var address = host + ":" + port;
        if (string.IsNullOrWhiteSpace(host) || string.IsNullOrWhiteSpace(port))
        {
            Console.WriteLine($"host或者port為空！");
            return app;
        }

        Console.WriteLine($"address={address}");
        var uri = new Uri(address);
        Console.WriteLine($"host={uri.Host},port={uri.Port}");

        var registration = new AgentServiceRegistration()
        {
            ID = $"MyService-{uri.Port}",
            Name = "MyService",
            Address = $"{uri.Host}",
            Port = uri.Port,
            Check = new AgentServiceCheck()
            {
                DeregisterCriticalServiceAfter = TimeSpan.FromSeconds(5),//服務(wù)啟動(dòng)多久后注冊(cè)
                Interval = TimeSpan.FromSeconds(10),//健康檢查時(shí)間間隔
                HTTP = $"{address}/HealthCheck",//健康檢查地址
                Timeout = TimeSpan.FromSeconds(5)//超時(shí)時(shí)間
            }
        };
        logger.LogInformation("Registering with Consul");
        logger.LogInformation($"Consul RegistrationID:{registration.ID}");
        //注銷
        consulClient.Agent.ServiceDeregister(registration.ID).ConfigureAwait(true);
        //注冊(cè)
        consulClient.Agent.ServiceRegister(registration).ConfigureAwait(true);
        //應(yīng)用程序關(guān)閉時(shí)候
        lifetime.ApplicationStopping.Register(() =>
        {
            //正在注銷
            logger.LogInformation("Unregistering from Consul");
            consulClient.Agent.ServiceDeregister(registration.ID).ConfigureAwait(true);
        });
        //每個(gè)服務(wù)都需要提供一個(gè)用于健康檢查的接口，該接口不具備業(yè)務(wù)功能。服務(wù)注冊(cè)時(shí)把這個(gè)接口的地址也告訴注冊(cè)中心，注冊(cè)中心會(huì)定時(shí)調(diào)用這個(gè)接口來檢測(cè)服務(wù)是否正常，如果不正常，則將它移除，這樣就保證了服務(wù)的可用性。
        app.Map("/HealthCheck", s =>
        {
            s.Run(async context =>
            {
                await context.Response.WriteAsync("ok");
            });
        });
        return app;
    }
}

[Route("api/[controller]")]
[ApiController]
public class ValuesController : ControllerBase
{
    // GET api/values
    [HttpGet]
    public ActionResult<IEnumerable<string>> Get()
    {
        var port = Request.Host.Port;
        return new string[] { "value1", "value2", port.Value.ToString() };
    }
}

"Consul": {
  "Host": "http://192.168.113.128:8500"
}

[Route("api/[controller]")]
[ApiController]
public class ValuesController : ControllerBase
{
    // GET api/values
    [HttpGet]
    public ActionResult<IEnumerable<string>> Get()
    {
        var port = Request.Host.Port;
        return new string[] { "value3", "value4", port.Value.ToString() };
    }
}

"Consul": {
  "Host": "http://192.168.113.128:8500"
}

services.AddConsulConfig(Configuration);

APIServiceA：app.UseConsul("http://172.168.18.73", "9999");
APIServiceB：app.UseConsul("http://172.168.18.73", "9998");