// Connect to the remote debugging server. If any errors occur, display an error dialog, and keep
// trying for as long as user clicks "Retry".
private static NodeRemoteDebugProcess Connect(NodeRemoteDebugPort port, INetworkClientFactory networkClientFactory)
{
if (port.Uri.Fragment == "#ping=0")
{
return(new NodeRemoteDebugProcess(port, "node.exe", String.Empty, String.Empty));
}
NodeRemoteDebugProcess process = null;
while (true)
{
Exception exception = null;
try {
LiveLogger.WriteLine("NodeRemoteEnumDebugProcesses pinging remote host ...");
using (var client = networkClientFactory.CreateNetworkClient(port.Uri))
using (var stream = client.GetStream()) {
// https://nodejstools.codeplex.com/workitem/578
// Node.js (V8) debugger is fragile during attach, and it's easy to put it into a bad state where it refuses
// future connections altogether, or accepts them but send responses that it queued up for another client.
// To avoid this, our ping needs to look like a proper debug session to the debuggee. For this, we need to
// do the following steps in order:
//
// 1. Receive the debugger's greeting message.
// 2. Send the "disconnect" request.
// 3. Receive the "disconnect" response.
//
// Only then can the socket be closed safely without disrupting V8.
// Receive greeting.
var buffer = new byte[1024];
int len = stream.ReadAsync(buffer, 0, buffer.Length, new CancellationTokenSource(5000).Token).GetAwaiter().GetResult();
string response = Encoding.UTF8.GetString(buffer, 0, len);
LiveLogger.WriteLine("NodeRemoteEnumDebugProcesses debugger greeting: " + response);
// There's no error code, so we have to do the string comparison. Luckily, it is hardcoded into V8 and is not localized.
if (response == "Remote debugging session already active\r\n")
{
throw new DebuggerAlreadyAttachedException();
}
// Send "disconnect" request.
string request = @"{""command"":""disconnect"",""seq"":1,""type"":""request"",""arguments"":null}";
request = string.Format(CultureInfo.InvariantCulture, "Content-Length: {0}\r\n\r\n{1}", request.Length, request);
buffer = Encoding.UTF8.GetBytes(request);
stream.WriteAsync(buffer, 0, buffer.Length, new CancellationTokenSource(5000).Token).GetAwaiter().GetResult();
// Receive "disconnect" response.
buffer = new byte[1024];
len = stream.ReadAsync(buffer, 0, buffer.Length, new CancellationTokenSource(5000).Token).GetAwaiter().GetResult();
response = Encoding.UTF8.GetString(buffer, 0, len);
LiveLogger.WriteLine("NodeRemoteEnumDebugProcesses debugger response: " + response);
// If we got to this point, the debuggee is behaving as expected, and we can report it as a valid Node.js process.
process = new NodeRemoteDebugProcess(port, "node.exe", String.Empty, String.Empty);
LiveLogger.WriteLine("NodeRemoteEnumDebugProcesses ping successful.");
break;
}
} catch (OperationCanceledException) {
LiveLogger.WriteLine("NodeRemoteEnumDebugProcesses ping timed out.");
} catch (DebuggerAlreadyAttachedException ex) {
LiveLogger.WriteLine("DebuggerAlreadyAttachedException connecting to remote debugger");
exception = ex;
} catch (AggregateException ex) {
LiveLogger.WriteLine("AggregateException connecting to remote debugger");
exception = ex;
} catch (IOException ex) {
LiveLogger.WriteLine("IOException connecting to remote debugger");
exception = ex;
} catch (InvalidOperationException ex) {
LiveLogger.WriteLine("InvalidOperationException connecting to remote debugger");
exception = ex;
} catch (SocketException ex) {
LiveLogger.WriteLine("SocketException connecting to remote debugger");
exception = ex;
} catch (WebSocketException ex) {
LiveLogger.WriteLine("WebSocketException connecting to remote debugger");
exception = ex;
} catch (PlatformNotSupportedException) {
LiveLogger.WriteLine("PlatformNotSupportedException connecting to remote debugger");
MessageBox.Show(
"Remote debugging of node.js Microsoft Azure applications is only supported on Windows 8 and above.",
null, MessageBoxButtons.OK, MessageBoxIcon.Error);
return(null);
}
if (exception != null)
{
while (exception.InnerException != null)
{
exception = exception.InnerException;
}
}
string errText = string.Format(CultureInfo.CurrentCulture,
"Could not attach to Node.js process at {0}{1}\r\n\r\n",
port.Uri,
exception != null ? ":\r\n\r\n" + exception.Message : ".");
if (!(exception is DebuggerAlreadyAttachedException))
{
if (port.Uri.Scheme == "ws" || port.Uri.Scheme == "wss")
{
errText +=
"Make sure that the Azure web site is deployed in the Debug configuration, and web sockets " +
"are enabled for it in the Azure management portal.";
}
else
{
errText += string.Format(CultureInfo.CurrentCulture,
"Make sure that the process is running behind the remote debug proxy (RemoteDebug.js), " +
"and the debugger port (default {0}) is open on the target host.",
NodejsConstants.DefaultDebuggerPort);
}
}
DialogResult dlgRes = MessageBox.Show(errText, null, MessageBoxButtons.RetryCancel, MessageBoxIcon.Error);
if (dlgRes != DialogResult.Retry)
{
break;
}
}
return(process);
}
public NodeRemoteEnumDebugPrograms(NodeRemoteDebugProcess process)
: base(new NodeRemoteDebugProgram(process))
{
}
public NodeRemoteDebugProgram(NodeRemoteDebugProcess process) {
_process = process;
}
public NodeRemoteDebugProgram(NodeRemoteDebugProcess process)
{
this._process = process;
}
