private async Task <(Uri url, CancellationToken hostExitToken)> StartIISExpressAsync(string contentRoot)
{
using (Logger.BeginScope("StartIISExpress"))
{
var iisExpressPath = GetIISExpressPath();
for (var attempt = 0; attempt < MaximumAttempts; attempt++)
{
var uri = TestUriHelper.BuildTestUri(ServerType.IISExpress, DeploymentParameters.ApplicationBaseUriHint);
var port = uri.Port;
if (port == 0)
{
port = (uri.Scheme == "https") ? TestPortHelper.GetNextSSLPort() : TestPortHelper.GetNextPort();
}
Logger.LogInformation("Attempting to start IIS Express on port: {port}", port);
PrepareConfig(contentRoot, port);
var parameters = string.IsNullOrEmpty(DeploymentParameters.ServerConfigLocation) ?
string.Format("/port:{0} /path:\"{1}\" /trace:error /systray:false", uri.Port, contentRoot) :
string.Format("/site:{0} /config:{1} /trace:error /systray:false", DeploymentParameters.SiteName, DeploymentParameters.ServerConfigLocation);
Logger.LogInformation("Executing command : {iisExpress} {parameters}", iisExpressPath, parameters);
var startInfo = new ProcessStartInfo
{
FileName = iisExpressPath,
Arguments = parameters,
UseShellExecute = false,
CreateNoWindow = true,
RedirectStandardError = true,
RedirectStandardOutput = true,
// VS sets current directory to C:\Program Files\IIS Express
WorkingDirectory = Path.GetDirectoryName(iisExpressPath)
};
AddEnvironmentVariablesToProcess(startInfo, DeploymentParameters.EnvironmentVariables);
Uri url = null;
var started = new TaskCompletionSource <bool>();
var process = new Process()
{
StartInfo = startInfo
};
process.OutputDataReceived += (sender, dataArgs) =>
{
if (string.Equals(dataArgs.Data, UnableToStartIISExpressMessage))
{
// We completely failed to start and we don't really know why
started.TrySetException(new InvalidOperationException("Failed to start IIS Express"));
}
else if (string.Equals(dataArgs.Data, FailedToInitializeBindingsMessage))
{
started.TrySetResult(false);
}
else if (string.Equals(dataArgs.Data, IISExpressRunningMessage))
{
started.TrySetResult(true);
}
else if (!string.IsNullOrEmpty(dataArgs.Data))
{
var m = UrlDetectorRegex.Match(dataArgs.Data);
if (m.Success)
{
url = new Uri(m.Groups["url"].Value);
}
}
};
process.EnableRaisingEvents = true;
var hostExitTokenSource = new CancellationTokenSource();
process.Exited += (sender, e) =>
{
Logger.LogInformation("iisexpress Process {pid} shut down", process.Id);
// If TrySetResult was called above, this will just silently fail to set the new state, which is what we want
started.TrySetException(new Exception($"Command exited unexpectedly with exit code: {process.ExitCode}"));
TriggerHostShutdown(hostExitTokenSource);
};
process.StartAndCaptureOutAndErrToLogger("iisexpress", Logger);
Logger.LogInformation("iisexpress Process {pid} started", process.Id);
if (process.HasExited)
{
Logger.LogError("Host process {processName} {pid} exited with code {exitCode} or failed to start.", startInfo.FileName, process.Id, process.ExitCode);
throw new Exception("Failed to start host");
}
// Wait for the app to start
// The timeout here is large, because we don't know how long the test could need
// We cover a lot of error cases above, but I want to make sure we eventually give up and don't hang the build
// just in case we missed one -anurse
if (!await started.Task.TimeoutAfter(TimeSpan.FromMinutes(10)))
{
Logger.LogInformation("iisexpress Process {pid} failed to bind to port {port}, trying again", process.Id, port);
// Wait for the process to exit and try again
process.WaitForExit(30 * 1000);
await Task.Delay(1000); // Wait a second to make sure the socket is completely cleaned up
}
else
{
_hostProcess = process;
// Ensure iisexpress.exe is killed if test process termination is non-graceful.
// Prevents locked files when stop debugging unit test.
ProcessTracker.Add(_hostProcess);
// cache the process start time for verifying log file name.
var _ = _hostProcess.StartTime;
Logger.LogInformation("Started iisexpress successfully. Process Id : {processId}, Port: {port}", _hostProcess.Id, port);
return(url : url, hostExitToken : hostExitTokenSource.Token);
}
}
var message = $"Failed to initialize IIS Express after {MaximumAttempts} attempts to select a port";
Logger.LogError(message);
throw new TimeoutException(message);
}
}