public class Program

{

public static async Task Main(string[] args)

{

var defaultFileToTail = args.FirstOrDefault();

// Configure app, logging, options...

var hostBuilder = new HostBuilder().UseContentRoot(Directory.GetCurrentDirectory())

.ConfigureHostConfiguration(b => BuildConfiguration(b))

.ConfigureAppConfiguration((wc, conf) => BuildConfiguration(conf, wc.HostingEnvironment.EnvironmentName))

.ConfigureServices((hostContext, services) =>

{ // Setup IoC container (just use default container for this)

services.AddLogging();

services.Configure<ConfigSettings>(hostContext.Configuration.GetSection("ConfigSettings"));

services.AddTransient<Func<TailFileType, IFileLineProcessor>>(s => t => FileLineProcessorFactory.Instance.ResolveProcessor(t, s));

services.AddTransient<Func<TailFileInfo, IFileSystemTailDelegate>>(s => t => new FileSystemTailFileDelegate(t,

s.GetRequiredService<ITailFileFailureDelegate>(),

s.GetRequiredService<IOptions<ConfigSettings>>(),

s.GetRequiredService<ILogger<FileSystemTailFileDelegate>>()));

services.AddSingleton<HttpAccessLogFileLineProcessor>();

services.AddSingleton<IHttpAccessLogLineParser, NaiveHttpAccessLogLineParser>();

services.AddSingleton<ITailFileFailureDelegate, RetryBackoffTailFileFailureDelegate>();

services.AddSingleton<ITailFileService, FileSystemTailFileService>();

// Host a file tail service for the default/specified file by default

services.AddTransient<IHostedService, DefaultHttpAccessLogHostedTail>(s => new DefaultHttpAccessLogHostedTail(s.GetRequiredService<ITailFileService>(),

s.GetRequiredService<IOptions<ConfigSettings>>(),

defaultFileToTail));

// Stat summary processing service

services.AddHostedService<StatSummaryService>();

// Storage service (simple in-memory for now)

services.AddSingleton<IHttpAccessLogStorageService>(s =>

{

var settings = s.GetRequiredService<IOptions<ConfigSettings>>();

return new InMemoryHttpAccessLogStorageService(settings.Value.TotalTrafficIntervalMinutes.Gz(2) + 1);

});

})

.ConfigureLogging((h, b) =>

{

b.ClearProviders();

b.SetMinimumLevel(LogLevel.Debug);

b.AddNLog();

})

.UseConsoleLifetime() // For purposes of this app, app lifetime is tied to the console

.Build();

await hostBuilder.RunAsync();

}

// The configuration produced by this method is used for both the host and app configurations.

private static void BuildConfiguration(IConfigurationBuilder conf, string envName = null)

{

var defaultEnv = "Development";

#if RELEASE

defaultEnv = "Production";

#endif

conf.AddJsonFile("appsettings.json", false, true)

.AddJsonFile($"appsettings.{envName ?? defaultEnv}.json", true,

true);

}

}