private async Task <SimpleSocket> SpawnServerFromService(string url)
{
// Ideally we would like to reuse Uri (or some other similar code), but it doesn't work without a Host
var parameterIndex = url.IndexOf('?');
var urlWithoutParameters = parameterIndex != -1 ? url.Substring(0, parameterIndex) : url;
string[] urlSegments;
string urlParameters;
RouterHelper.ParseUrl(url, out urlSegments, out urlParameters);
// Find a matching server
TaskCompletionSource <SimpleSocket> serviceTCS;
lock (registeredServices)
{
if (!registeredServices.TryGetValue(urlWithoutParameters, out serviceTCS))
{
serviceTCS = new TaskCompletionSource <SimpleSocket>();
registeredServices.Add(urlWithoutParameters, serviceTCS);
}
if (!serviceTCS.Task.IsCompleted)
{
if (urlSegments.Length < 3)
{
Log.Error("{0} action URL {1} is invalid", RouterMessage.ClientRequestServer, url);
throw new InvalidOperationException();
}
var paradoxVersion = urlSegments[1];
var serviceExe = urlSegments[2];
var paradoxSdkDir = RouterHelper.FindParadoxSdkDir(paradoxVersion);
if (paradoxSdkDir == null)
{
Log.Error("{0} action URL {1} references a Paradox version which is not installed", RouterMessage.ClientRequestServer, url);
throw new InvalidOperationException();
}
var servicePath = Path.Combine(paradoxSdkDir, @"Bin\Windows-Direct3D11", serviceExe);
RunServiceProcessAndLog(servicePath);
}
}
var service = await serviceTCS.Task;
// Generate connection Guid
var guid = Guid.NewGuid();
var serverSocketTCS = new TaskCompletionSource <SimpleSocket>();
lock (pendingServers)
{
pendingServers.Add(guid, serverSocketTCS);
}
// Notify service that we want it to establish back a new connection to us for this client
await service.WriteStream.WriteInt16Async((short)RouterMessage.ServiceRequestServer);
await service.WriteStream.WriteStringAsync(url);
await service.WriteStream.WriteGuidAsync(guid);
await service.WriteStream.FlushAsync();
// Should answer within 2 sec
var ct = new CancellationTokenSource(2000);
ct.Token.Register(() => serverSocketTCS.TrySetException(new TimeoutException("Server could not connect back in time")));
// Wait for such a server to be available
return(await serverSocketTCS.Task);
}
/// <summary>
/// Handles ClientRequestServer messages.
/// It will try to find a matching service (spawn it if not started yet), and ask it to establish a new "server" connection back to us.
/// </summary>
/// <param name="clientSocket">The client socket context.</param>
/// <returns></returns>
private async Task HandleMessageClientRequestServer(SimpleSocket clientSocket)
{
// Check for an existing server
// TODO: Proper Url parsing (query string)
var url = await clientSocket.ReadStream.ReadStringAsync();
string[] urlSegments;
string urlParameters;
RouterHelper.ParseUrl(url, out urlSegments, out urlParameters);
if (urlSegments.Length == 0)
{
throw new InvalidOperationException("No URL Segments");
}
SimpleSocket serverSocket = null;
ExceptionDispatchInfo serverSocketCapturedException = null;
try
{
// For now, we handle only "service" URL
switch (urlSegments[0])
{
case "service":
{
// From the URL, start service (if not started yet) and ask it to provide a server
serverSocket = await SpawnServerFromService(url);
break;
}
default:
throw new InvalidOperationException("This type of URL is not supported");
}
}
catch (Exception e)
{
serverSocketCapturedException = ExceptionDispatchInfo.Capture(e);
}
if (serverSocketCapturedException != null)
{
try
{
// Notify client that there was an error
await clientSocket.WriteStream.WriteInt16Async((short)RouterMessage.ClientServerStarted);
await clientSocket.WriteStream.WriteInt32Async(1); // error code Failure
await clientSocket.WriteStream.WriteStringAsync(serverSocketCapturedException.SourceException.Message);
await clientSocket.WriteStream.FlushAsync();
}
finally
{
serverSocketCapturedException.Throw();
}
}
try
{
// Notify client that we've found a server for it
await clientSocket.WriteStream.WriteInt16Async((short)RouterMessage.ClientServerStarted);
await clientSocket.WriteStream.WriteInt32Async(0); // error code OK
await clientSocket.WriteStream.FlushAsync();
// Let's forward clientSocketContext and serverSocketContext
await await Task.WhenAny(
ForwardSocket(clientSocket, serverSocket),
ForwardSocket(serverSocket, clientSocket));
}
catch
{
serverSocket.Dispose();
throw;
}
}