Startup.cs

using System;
using System.Linq;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.Bot.Builder;
using Microsoft.Bot.Builder.Integration.AspNet.Core;
using Microsoft.Bot.Configuration;
using Microsoft.Bot.Connector.Authentication;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Options;

namespace BotFrameworkTemplate
{
    public class Startup
    {
        private bool _isProduction = false;

        /// <summary>
        /// Initializes a new instance of the <see cref="Startup"/> class.
        /// This method gets called by the runtime. Use this method to add services to the container.
        /// For more information on how to configure your application, visit https://go.microsoft.com/fwlink/?LinkID=398940.
        /// </summary>
        /// <param name="env">Provides information about the web hosting environment an application is running in.</param>
        /// <seealso cref="https://docs.microsoft.com/en-us/aspnet/core/fundamentals/startup?view=aspnetcore-2.1"/>
        public Startup(IHostingEnvironment env)
        {
            _isProduction = true;//env.IsProduction();

            var builder = new ConfigurationBuilder()
                .SetBasePath(env.ContentRootPath)
                .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
                .AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true)
                .AddEnvironmentVariables();

            Configuration = builder.Build();
        }

        /// <summary>
        /// Gets the configuration that represents a set of key/value application configuration properties.
        /// </summary>
        /// <value>
        /// The <see cref="IConfiguration"/> that represents a set of key/value application configuration properties.
        /// </value>
        public IConfiguration Configuration { get; }

        /// <summary>
        /// This method gets called by the runtime. Use this method to add services to the container.
        /// </summary>
        /// <param name="services">Specifies the contract for a <see cref="IServiceCollection"/> of service descriptors.</param>
        public void ConfigureServices(IServiceCollection services)
        {
            var secretKey = Configuration.GetSection("botFileSecret")?.Value;
            var botFilePath = Configuration.GetSection("botFilePath")?.Value;

            // Loads .bot configuration file and adds a singleton that your Bot can access through dependency injection.
            var botConfig = BotConfiguration.Load(botFilePath ?? @".\BotConfiguration.bot", secretKey);
            services.AddSingleton(sp => botConfig ?? throw new InvalidOperationException($"The .bot config file could not be loaded. ({botConfig})"));

            // Retrieve current endpoint.
            var environment = _isProduction ? "production" : "development";
            var service = botConfig.Services.Where(s => s.Type == "endpoint" && s.Name == environment).FirstOrDefault();
            if (!(service is EndpointService endpointService))
            {
                throw new InvalidOperationException($"The .bot file does not contain an endpoint with name '{environment}'.");
            }

            services.AddBot<EchoBot>(options =>
            {
                options.CredentialProvider = new SimpleCredentialProvider(endpointService.AppId, endpointService.AppPassword);
            });
        }

        /// <summary>
        /// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        /// </summary>
        /// <param name="app">Application Builder.</param>
        /// <param name="env">Hosting Environment.</param>
        public void Configure(IApplicationBuilder app)
        {
            app.UseDefaultFiles()
                .UseStaticFiles()
                .UseBotFramework();
        }
    }
}