Startup.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;

namespace ConfigClient
{
    public class Startup
    {
        public Startup(IHostingEnvironment env)
        {
            var builder = new ConfigurationBuilder()
                .SetBasePath(env.ContentRootPath)
                .AddJsonFile("appsettings.json", optional: false, reloadOnChange: true)
                .AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true)
                .AddEtcdConfiguration(new EtcdConnectionOptions
                {
                    Urls = new string[] {
                    "https://portal1934-21.euphoric-etcd-31.capital-one-3.composedb.com:17174",
                    "https://portal2016-22.euphoric-etcd-31.capital-one-3.composedb.com:17174"
                     },
                    Username = "root",
                    Password = "changeme",
                    RootKey = "/myapp"
                })
                .AddEnvironmentVariables();
            Configuration = builder.Build();
        }

        public static IConfigurationRoot Configuration { get; set; }

        // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services)
        {
            // Add framework services.
            services.AddMvc();
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
        {
            loggerFactory.AddConsole();
            loggerFactory.AddDebug();

            app.UseMvc();
        }
    }
}