Program.cs

// ------------------------------------------------------------
// Copyright (c) Microsoft Corporation.
// Licensed under the MIT License.
// ------------------------------------------------------------

namespace MessageAnalyzer
{
    using Dapr.Tests.Common;
    using Microsoft.AspNetCore.Hosting;
    using Microsoft.Extensions.Configuration;
    using Microsoft.Extensions.Hosting;
    using Microsoft.Extensions.Logging;
    using System;
    using System.IO;

    public class AppSettings {
        public const string DaprHTTPAppPort = "DaprHTTPAppPort";
    }

    /// <summary>
    /// MessageAnalyzer - receives messages from Dapr through pub/sub, adds a 
    /// sentiment, and sends them to an output binding.
    /// </summary>
    public class MessageAnalyzer
    {
        /// <summary>
        /// Main for MessageAnalyzer.
        /// </summary>
        /// <param name="args">Arguments.</param>
        public static void Main(string[] args)
        {
            ObservabilityUtils.StartMetricsServer();

            CreateHostBuilder(args).Build().Run();
        }

        /// <summary>
        /// Creates WebHost Builder.
        /// </summary>
        /// <param name="args">Arguments.</param>
        /// <returns>Returns IHostbuilder.</returns>
        public static IHostBuilder CreateHostBuilder(string[] args) =>
            Host.CreateDefaultBuilder(args)
                .ConfigureTestInfraLogging()
                .ConfigureWebHostDefaults(webBuilder =>
                {
                    var appSettings = new ConfigurationBuilder()
                        .SetBasePath(Directory.GetCurrentDirectory())
                        .AddJsonFile($"appsettings.json", optional: true, reloadOnChange: true)                        
                        .AddCommandLine(args)
                        .Build();

                    var host = webBuilder.UseStartup<Startup>()
                        .UseUrls(urls: $"http://*:{appSettings[AppSettings.DaprHTTPAppPort]}");
                });
    }
}