private async Task Inner(AsyncLocalContext <Guid> ctx, Guid expected)
{
Assert.That(ctx.Value, Is.EqualTo(expected), "Inner pre");
await Task.Delay(1000);
Assert.That(ctx.Value, Is.EqualTo(expected), "Inner post");
}
public void It_should_set_and_get_value()
{
var ctx = new AsyncLocalContext <object>();
var expected = new object();
ctx.Value = expected;
Assert.That(ctx.Value, Is.SameAs(expected));
}
public async Task Async_tasks_should_share_the_context()
{
var ctx = new AsyncLocalContext <Guid>();
var task1 = Outer(ctx, Guid.NewGuid());
var task2 = Outer(ctx, Guid.NewGuid());
var task3 = Outer(ctx, Guid.NewGuid());
await Task.WhenAll(task1, task2, task3);
}
/// <summary>
/// Gets a value associated with the given key in the current scope.
/// </summary>
/// <param name="key">The key to look up.</param>
/// <returns>The value associated with the key, or null of the value was not set.</returns>
public static object GetValue(string key)
{
var data = (TraceContext)AsyncLocalContext.GetData(_slot);
if (data == null)
{
return(null);
}
return(data[key]);
}
private async Task Outer(AsyncLocalContext <Guid> ctx, Guid expected)
{
ctx.Value = expected;
await Task.Yield();
Assert.That(ctx.Value, Is.EqualTo(expected), "Outer pre");
await Task.Delay(1000);
await Task.WhenAll(Inner(ctx, expected), Inner(ctx, expected), Inner(ctx, expected));
Assert.That(ctx.Value, Is.EqualTo(expected), "Outer post");
}
private static Guid GetActivityId()
{
// if we have stored a guid, then return that
var data = AsyncLocalContext.GetData(_slot);
if (data != null)
{
return((Guid)data);
}
return(Guid.Empty);
}
public async Task Async_tasks_should_not_interfere_each_other()
{
var ctx = new AsyncLocalContext <object>();
Func <object, Task> func = async expected =>
{
ctx.Value = expected;
await Task.Delay(500);
Assert.That(ctx.Value, Is.EqualTo(expected));
};
await Task.WhenAll(func(new object()), func(new object()), func(null));
}
private static void SetActivityId(Guid activityId)
{
// never store the empty guid, just convert it to null and revert to the system activity ID
if (activityId == Guid.Empty)
{
AsyncLocalContext.SetData(_slot, null);
UnsafeNativeMethods.SetActivityId(Trace.CorrelationManager.ActivityId);
}
else
{
AsyncLocalContext.SetData(_slot, activityId);
UnsafeNativeMethods.SetActivityId(activityId);
}
}
public void It_should_allow_to_override_value()
{
var ctx = new AsyncLocalContext <object>();
var expected = new object();
var expected2 = new object();
ctx.Value = expected;
Assert.That(ctx.Value, Is.SameAs(expected));
ctx.Value = expected2;
Assert.That(ctx.Value, Is.SameAs(expected2));
ctx.Value = null;
Assert.That(ctx.Value, Is.Null);
}
/// <summary>
/// Starts a new TraceContext scope.
/// </summary>
/// <returns>The new TraceContext that can be filled in.</returns>
public static TraceContext Begin()
{
var data = (TraceContext)AsyncLocalContext.GetData(_slot);
TraceContext context = null;
try
{
context = new TraceContext(data);
AsyncLocalContext.SetData(_slot, context);
}
catch
{
context.Dispose();
throw;
}
return(context);
}
/// <summary>
/// Ends the TraceContext scope.
/// </summary>
private void End()
{
AsyncLocalContext.SetData(_slot, _baseContext);
}
