ASP.NET Core 1.1. Use the given configuration settings on the web host. Compatible with the configuration section. Fix https://github.com/aspnet/Hosting/issues/839

WebHostConfigurationSection.cs

using Microsoft.Extensions.Configuration;

namespace Microsoft.AspNetCore.Hosting
{
    public static class WebHostConfigurationSection
    {
        /// <summary>
        /// Use the given configuration settings on the web host. Compatible with the configuration section.
        /// </summary>
        /// <param name="hostBuilder">The <see cref="IWebHostBuilder"/> to configure.</param>
        /// <param name="configuration">The <see cref="IConfiguration"/> containing settings to be used.</param>
        /// <returns>The <see cref="IWebHostBuilder"/>.</returns>
        public static IWebHostBuilder UseConfigurationSection(this IWebHostBuilder hostBuilder, IConfiguration configuration)
        {
            foreach (var setting in configuration.AsEnumerable(true))
            {
                hostBuilder.UseSetting(setting.Key, setting.Value);
            }

            return hostBuilder;
        }
    }
}

WebHostConfigurationSection.example.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Configuration;

namespace WebApplication
{
    public class Program
    {
        public static void Main(string[] args)
        {
            var config = new ConfigurationBuilder()
                .SetBasePath(Directory.GetCurrentDirectory())
                .AddJsonFile("appsettings.json", optional: true)
                .Build();

            var host = new WebHostBuilder()
                .UseConfigurationSection(config.GetSection("kestrel"))
                .UseKestrel()
                .UseContentRoot(Directory.GetCurrentDirectory())
                .UseIISIntegration()
                .UseStartup<Startup>()
                .Build();

            host.Run();
        }
    }
}