Program.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Serilog;
using Serilog.Formatting.Compact;

namespace FileQueueWatcher
{
    public class Program
    {
        public static void Main(string[] args)
        {
            SetupStaticLogger();
            CreateHostBuilder(args).Build().Run();
        }

        private static void SetupStaticLogger()
        {
            var environmentName = Environment.GetEnvironmentVariable("DOTNET_ENVIRONMENT");
            var configuration = new ConfigurationBuilder()
                .AddJsonFile($"appsettings.{environmentName}.json")
                .Build();

            Log.Logger = new LoggerConfiguration()
                .ReadFrom.Configuration(configuration)
                .CreateLogger();
        }

        public static IHostBuilder CreateHostBuilder(string[] args) =>
            Host.CreateDefaultBuilder(args)
                .ConfigureServices((hostContext, services) =>
                {
                    services.AddHostedService<DirectoryMonitorWorker>();
                });
    }
}