private GetTokenOperation CreateOperation(
VssTraceActivity traceActivity,
IssuedToken failedToken,
CancellationToken cancellationToken,
out GetTokenOperation operationInProgress)
{
operationInProgress = null;
GetTokenOperation operation = null;
lock (m_thisLock)
{
if (m_operations == null)
{
m_operations = new List <GetTokenOperation>();
}
// Grab the main operation which is doing the work (if any)
if (m_operations.Count > 0)
{
operationInProgress = m_operations[0];
// Use the existing completion source when creating the new operation
operation = new GetTokenOperation(traceActivity, this, failedToken, cancellationToken, operationInProgress.CompletionSource);
}
else
{
operation = new GetTokenOperation(traceActivity, this, failedToken, cancellationToken);
}
m_operations.Add(operation);
}
return(operation);
}
private static Task <IssuedToken> PostCallback(
Object state,
CancellationTokenSource timeoutTokenSource)
{
// Make sure that we were not cancelled (timed out) before this callback is invoked.
using (timeoutTokenSource)
{
timeoutTokenSource.CancelAfter(-1);
if (timeoutTokenSource.IsCancellationRequested)
{
return(Task.FromResult <IssuedToken>(null));
}
}
GetTokenOperation thisPtr = (GetTokenOperation)state;
return(thisPtr.Provider.OnGetTokenAsync(thisPtr.FailedToken, thisPtr.CancellationToken));
}
/// <summary>
/// Retrieves a token for the credentials.
/// </summary>
/// <param name="failedToken">The token which previously failed authentication, if available</param>
/// <param name="cancellationToken">The <c>CancellationToken</c>that will be assigned to the new task</param>
/// <returns>A security token for the current credentials</returns>
public async Task <IssuedToken> GetTokenAsync(
IssuedToken failedToken,
CancellationToken cancellationToken)
{
IssuedToken currentToken = this.CurrentToken;
VssTraceActivity traceActivity = VssTraceActivity.Current;
Stopwatch aadAuthTokenTimer = Stopwatch.StartNew();
try
{
VssHttpEventSource.Log.AuthenticationStart(traceActivity);
if (currentToken != null)
{
VssHttpEventSource.Log.IssuedTokenRetrievedFromCache(traceActivity, this, currentToken);
return(currentToken);
}
else
{
GetTokenOperation operation = null;
try
{
GetTokenOperation operationInProgress;
operation = CreateOperation(traceActivity, failedToken, cancellationToken, out operationInProgress);
if (operationInProgress == null)
{
return(await operation.GetTokenAsync(traceActivity).ConfigureAwait(false));
}
else
{
return(await operationInProgress.WaitForTokenAsync(traceActivity, cancellationToken).ConfigureAwait(false));
}
}
finally
{
lock (m_thisLock)
{
m_operations.Remove(operation);
}
operation?.Dispose();
}
}
}
finally
{
VssHttpEventSource.Log.AuthenticationStop(traceActivity);
aadAuthTokenTimer.Stop();
TimeSpan getTokenTime = aadAuthTokenTimer.Elapsed;
if (getTokenTime.TotalSeconds >= c_slowTokenAcquisitionTimeInSeconds)
{
// It may seem strange to pass the string value of TotalSeconds into this method, but testing
// showed that ETW is persnickety when you register a method in an EventSource that doesn't
// use strings or integers as its parameters. It is easier to simply give the method a string
// than figure out to get ETW to reliably accept a double or TimeSpan.
VssHttpEventSource.Log.AuthorizationDelayed(getTokenTime.TotalSeconds.ToString());
}
}
}
