public virtual async Task StartAsync(CancellationToken cancellationToken = default)
{
Debug.Assert(_applicationServices != null, "Initialize must be called first.");
HostingEventSource.Log.HostStart();
_logger = _applicationServices.GetRequiredService <ILoggerFactory>().CreateLogger("Microsoft.AspNetCore.Hosting.Diagnostics");
_logger.Starting();
var application = BuildApplication();
_applicationLifetime = _applicationServices.GetRequiredService <ApplicationLifetime>();
_hostedServiceExecutor = _applicationServices.GetRequiredService <HostedServiceExecutor>();
// Fire IHostedService.Start
await _hostedServiceExecutor.StartAsync(cancellationToken).ConfigureAwait(false);
var diagnosticSource = _applicationServices.GetRequiredService <DiagnosticListener>();
var activitySource = _applicationServices.GetRequiredService <ActivitySource>();
var httpContextFactory = _applicationServices.GetRequiredService <IHttpContextFactory>();
var hostingApp = new HostingApplication(application, _logger, diagnosticSource, activitySource, httpContextFactory);
await Server.StartAsync(hostingApp, cancellationToken).ConfigureAwait(false);
_startedServer = true;
// Fire IApplicationLifetime.Started
_applicationLifetime?.NotifyStarted();
_logger.Started();
// Log the fact that we did load hosting startup assemblies.
if (_logger.IsEnabled(LogLevel.Debug))
{
foreach (var assembly in _options.GetFinalHostingStartupAssemblies())
{
_logger.StartupAssemblyLoaded(assembly);
}
}
if (_hostingStartupErrors != null)
{
foreach (var exception in _hostingStartupErrors.InnerExceptions)
{
_logger.HostingStartupAssemblyError(exception);
}
}
}
public async Task StartAsync(CancellationToken cancellationToken)
{
HostingEventSource.Log.HostStart();
var serverAddressesFeature = Server.Features?.Get <IServerAddressesFeature>();
var addresses = serverAddressesFeature?.Addresses;
if (addresses != null && !addresses.IsReadOnly && addresses.Count == 0)
{
var urls = Configuration[WebHostDefaults.ServerUrlsKey];
if (!string.IsNullOrEmpty(urls))
{
serverAddressesFeature.PreferHostingUrls = WebHostUtilities.ParseBool(Configuration, WebHostDefaults.PreferHostingUrlsKey);
foreach (var value in urls.Split(new[] { ';' }, StringSplitOptions.RemoveEmptyEntries))
{
addresses.Add(value);
}
}
}
RequestDelegate application = null;
try
{
Action <IApplicationBuilder> configure = Options.ConfigureApplication;
if (configure == null)
{
throw new InvalidOperationException($"No application configured. Please specify an application via IWebHostBuilder.UseStartup, IWebHostBuilder.Configure, or specifying the startup assembly via {nameof(WebHostDefaults.StartupAssemblyKey)} in the web host configuration.");
}
var builder = ApplicationBuilderFactory.CreateBuilder(Server.Features);
foreach (var filter in StartupFilters.Reverse())
{
configure = filter.Configure(configure);
}
configure(builder);
// Build the request pipeline
application = builder.Build();
}
catch (Exception ex)
{
Logger.ApplicationError(ex);
if (!Options.WebHostOptions.CaptureStartupErrors)
{
throw;
}
application = BuildErrorPageApplication(ex);
}
var httpApplication = new HostingApplication(application, Logger, DiagnosticListener, HttpContextFactory);
await Server.StartAsync(httpApplication, cancellationToken);
if (addresses != null)
{
foreach (var address in addresses)
{
LifetimeLogger.LogInformation("Now listening on: {address}", address);
}
}
if (Logger.IsEnabled(LogLevel.Debug))
{
foreach (var assembly in Options.WebHostOptions.GetFinalHostingStartupAssemblies())
{
Logger.LogDebug("Loaded hosting startup assembly {assemblyName}", assembly);
}
}
if (Options.HostingStartupExceptions != null)
{
foreach (var exception in Options.HostingStartupExceptions.InnerExceptions)
{
Logger.HostingStartupAssemblyError(exception);
}
}
}