public async Task CreateAndRun(string rHome, string rhostDirectory = null, string rCommandLineArguments = null, int timeout = 3000, CancellationToken ct = default(CancellationToken))
{
await TaskUtilities.SwitchToBackgroundThread();
rhostDirectory = rhostDirectory ?? Path.GetDirectoryName(typeof(RHost).Assembly.GetAssemblyPath());
rCommandLineArguments = rCommandLineArguments ?? string.Empty;
string rhostExe = Path.Combine(rhostDirectory, RHostExe);
string rBinPath = Path.Combine(rHome, RBinPathX64);
if (!File.Exists(rhostExe))
{
throw new RHostBinaryMissingException();
}
// Grab an available port from the ephemeral port range (per RFC 6335 8.1.2) for the server socket.
WebSocketServer server = null;
var rnd = new Random();
const int ephemeralRangeStart = 49152;
var ports =
from port in Enumerable.Range(ephemeralRangeStart, 0x10000 - ephemeralRangeStart)
let pos = rnd.NextDouble()
orderby pos
select port;
foreach (var port in ports)
{
ct.ThrowIfCancellationRequested();
server = new WebSocketServer(port)
{
ReuseAddress = false
};
server.AddWebSocketService("/", CreateWebSocketMessageTransport);
try {
server.Start();
break;
} catch (SocketException ex) {
if (ex.SocketErrorCode == SocketError.AddressAlreadyInUse)
{
server = null;
}
else
{
throw new MessageTransportException(ex);
}
} catch (WebSocketException ex) {
throw new MessageTransportException(ex);
}
}
if (server == null)
{
throw new MessageTransportException(new SocketException((int)SocketError.AddressAlreadyInUse));
}
var psi = new ProcessStartInfo {
FileName = rhostExe,
UseShellExecute = false
};
psi.EnvironmentVariables["R_HOME"] = rHome;
psi.EnvironmentVariables["PATH"] = Environment.GetEnvironmentVariable("PATH") + ";" + rBinPath;
if (_name != null)
{
psi.Arguments += " --rhost-name " + _name;
}
psi.Arguments += Invariant($" --rhost-connect ws://127.0.0.1:{server.Port}");
if (!showConsole)
{
psi.CreateNoWindow = true;
}
if (!string.IsNullOrWhiteSpace(rCommandLineArguments))
{
psi.Arguments += Invariant($" {rCommandLineArguments}");
}
using (this)
using (_process = Process.Start(psi)) {
_log.RHostProcessStarted(psi);
_process.EnableRaisingEvents = true;
_process.Exited += delegate { Dispose(); };
try {
ct = CancellationTokenSource.CreateLinkedTokenSource(ct, _cts.Token).Token;
// Timeout increased to allow more time in test and code coverage runs.
await Task.WhenAny(_transportTcs.Task, Task.Delay(timeout)).Unwrap();
if (!_transportTcs.Task.IsCompleted)
{
_log.FailedToConnectToRHost();
throw new RHostTimeoutException("Timed out waiting for R host process to connect");
}
await Run(null, ct);
} catch (Exception) {
// TODO: delete when we figure out why host occasionally times out in code coverage runs.
//await _log.WriteFormatAsync(MessageCategory.Error, "Exception running R Host: {0}", ex.Message);
throw;
} finally {
if (!_process.HasExited)
{
try {
_process.WaitForExit(500);
if (!_process.HasExited)
{
_process.Kill();
_process.WaitForExit();
}
} catch (InvalidOperationException) {
}
}
_log.RHostProcessExited();
}
}
}