private static async Task PerformHandshakeAsync(IPC ipc)
{
// Do a two-way handshake with the browser, this ensures that the appropriate
// interop handlers have been set up before control returns to the user.
//
// The handshake sequence looks like this:
//
// 1. dotnet starts listening for components:init
// 2. dotnet sends components:init repeatedly
// 3. JS starts listening for components:init
// 4. JS sends a components:init once it has received one from dotnet - it's ready
// 5. dotnet receives components:init - it's ready
//
// Because either side might take any amount of time to start listening,
// step 3 can occur at any point prior to step 4. The whole process works
// because steps 1, 2, 4, and 5 can only occur in that order
var cts = new CancellationTokenSource();
var incomingHandshakeCancellationToken = cts.Token;
ipc.Once("components:init", args =>
{
var argsArray = (object[])args;
InitialUriAbsolute = ((JsonElement)argsArray[0]).GetString();
BaseUriAbsolute = ((JsonElement)argsArray[1]).GetString();
cts.Cancel();
});
Log("Waiting for interop connection");
while (!incomingHandshakeCancellationToken.IsCancellationRequested)
{
ipc.Send("components:init");
try
{
await Task.Delay(100, incomingHandshakeCancellationToken);
}
catch (TaskCanceledException)
{
}
}
Log("Interop connected");
}
private static async Task RunAsync <TStartup>(IPC ipc, CancellationToken appLifetime)
{
DesktopJSRuntime = new DesktopJSRuntime(ipc);
await PerformHandshakeAsync(ipc);
AttachJsInterop(ipc, appLifetime);
var serviceCollection = new ServiceCollection();
serviceCollection.AddLogging(configure => configure.AddConsole());
serviceCollection.AddSingleton <NavigationManager>(DesktopNavigationManager.Instance);
serviceCollection.AddSingleton <IJSRuntime>(DesktopJSRuntime);
serviceCollection.AddSingleton <INavigationInterception, DesktopNavigationInterception>();
var startup = new ConventionBasedStartup(Activator.CreateInstance(typeof(TStartup)));
startup.ConfigureServices(serviceCollection);
var services = serviceCollection.BuildServiceProvider();
var builder = new DesktopApplicationBuilder(services);
startup.Configure(builder, services);
var loggerFactory = services.GetRequiredService <ILoggerFactory>();
DesktopRenderer = new DesktopRenderer(services, ipc, loggerFactory);
DesktopRenderer.UnhandledException += (sender, exception) =>
{
Console.Error.WriteLine(exception);
};
foreach (var rootComponent in builder.Entries)
{
_ = DesktopRenderer.AddComponentAsync(rootComponent.componentType, rootComponent.domElementSelector);
}
}
public DesktopRenderer(IServiceProvider serviceProvider, IPC ipc, ILoggerFactory loggerFactory)
: base(serviceProvider, loggerFactory)
{
_ipc = ipc ?? throw new ArgumentNullException(nameof(ipc));
_jsRuntime = serviceProvider.GetRequiredService <IJSRuntime>();
}
public DesktopJSRuntime(IPC ipc)
{
_ipc = ipc ?? throw new ArgumentNullException(nameof(ipc));
}