public CustomAwaitable(string url)
{
ctx = SynchronizationContext.Current;
this.task = TaskEx.RunEx(
() =>
{
var req = (HttpWebRequest)WebRequest.Create(url);
req.Method = "HEAD";
var resp = (HttpWebResponse)req.GetResponse();
return(this.FormatHeaders(resp.Headers));
});
}
public void TestAsync()
{
const int taskCount = 5000;
// Create an asynchronous context in which to run.
AsyncContext.Run(
async()
=>
{
Task[] tasks = new Task[taskCount];
for (int a = 0; a < taskCount; a++)
{
tasks[a] = TaskEx.RunEx(
async() =>
{
ContextStack <string> stack = new ContextStack <string>();
TaskCompletionSource tcs1 = new TaskCompletionSource();
TaskCompletionSource tcs2 = new TaskCompletionSource();
TaskCompletionSource tcs3 = new TaskCompletionSource();
string randomString = Guid.NewGuid().ToString();
string randomString2 = Guid.NewGuid().ToString();
using (stack.Region(randomString))
{
// Check we have 'A' in the current stack.
Assert.AreEqual(randomString, stack.Current);
Assert.AreEqual(1, stack.CurrentStack.Count());
Assert.AreEqual(randomString, stack.CurrentStack.Last());
int threadId = Thread.CurrentThread.ManagedThreadId;
// Await the task
await TaskEx.Delay(500);
// Check we still have 'A' in the current stack.
Assert.AreEqual(randomString, stack.Current);
Assert.AreEqual(1, stack.CurrentStack.Count());
Assert.AreEqual(randomString, stack.CurrentStack.Last());
// Create new thread.
Task task = TaskEx.RunEx(
async() =>
{
int task2Thread = Thread.CurrentThread.ManagedThreadId;
// Assess if this is a new thread
if (threadId != task2Thread)
{
Interlocked.Increment(ref _task2NewThread);
}
// Check we have 'A' in the current stack.
Assert.AreEqual(randomString,
stack.Current);
Assert.AreEqual(1, stack.CurrentStack.Count());
Assert.AreEqual(randomString,
stack.CurrentStack.Last());
// Wait for the first signal
await tcs1.Task;
// Check we still have 'A' in the current stack (i.e. we're not affected by additions in first thread.
Assert.AreEqual(randomString, stack.Current);
Assert.AreEqual(1, stack.CurrentStack.Count());
Assert.AreEqual(randomString,
stack.CurrentStack.Last());
// Add C to stack.
using (stack.Region("C"))
{
// We should have A, C in stack now.
Assert.AreEqual("C", stack.Current);
Assert.AreEqual(2,
stack.CurrentStack.Count());
Assert.AreEqual(randomString,
stack.CurrentStack.First());
// Second signal
tcs2.SetResult();
// Wait for the 3rd signal
await tcs3.Task;
// We should still have A, C in stack now.
Assert.AreEqual("C", stack.Current);
Assert.AreEqual(2,
stack.CurrentStack.Count());
Assert.AreEqual(randomString,
stack.CurrentStack.First());
}
// Back to just having C.
Assert.AreEqual(randomString, stack.Current);
Assert.AreEqual(1, stack.CurrentStack.Count());
Assert.AreEqual(randomString,
stack.CurrentStack.Last());
// Wait a bit before finishing.
await TaskEx.Delay(100);
if (task2Thread !=
Thread.CurrentThread.ManagedThreadId)
{
Interlocked.Increment(
ref _task2ThreadSwitch);
}
});
// Add B to stack.
using (stack.Region(randomString2))
{
// We should have A, B in stack now.
Assert.AreEqual(randomString2, stack.Current);
Assert.AreEqual(2, stack.CurrentStack.Count());
Assert.AreEqual(randomString, stack.CurrentStack.First());
// Signal 2nd task with first signal.
tcs1.SetResult();
// Wait for 2nd task to signal back with 2nd second.
await tcs2.Task;
// We should still have A, B in stack now.
Assert.AreEqual(randomString2, stack.Current);
Assert.AreEqual(2, stack.CurrentStack.Count());
Assert.AreEqual(randomString, stack.CurrentStack.First());
// Signal 2nd task with third signal
tcs3.SetResult();
// Wait for task to finish.
await task;
// We should still have A, B in stack now.
Assert.AreEqual(randomString2, stack.Current);
Assert.AreEqual(2, stack.CurrentStack.Count());
Assert.AreEqual(randomString, stack.CurrentStack.First());
}
// We should just have A in stack.
Assert.AreEqual(randomString, stack.Current);
Assert.AreEqual(1, stack.CurrentStack.Count());
if (threadId != Thread.CurrentThread.ManagedThreadId)
{
Interlocked.Increment(ref _task1ThreadSwitch);
}
}
// The stack should be empty
Assert.IsNull(stack.Current);
Assert.AreEqual(0, stack.CurrentStack.Count());
});
}
await TaskEx.WhenAll(tasks);
});
Trace.WriteLine(
String.Format(
"Task1 Thread Switch: {1}{0}Task2 Thread Switch: {2}{0}Task2 new thread: {3}{0}Total tasks: {4}",
Environment.NewLine,
_task1ThreadSwitch,
_task2ThreadSwitch,
_task2NewThread,
taskCount));
}