/// <summary>
/// Wraps a <see cref="Task"/> into the Begin method of an APM pattern.
/// </summary>
/// <param name="task">The task to wrap.</param>
/// <param name="callback">The callback method passed into the Begin method of the APM pattern.</param>
/// <param name="descriptor">The state passed into the Begin method of the APM pattern.</param>
/// <returns>The asynchronous operation, to be returned by the Begin method of the APM pattern.</returns>
protected IAsyncResult BeginInvoke(Task task, AsyncCallback callback, ConsumerDescriptor descriptor)
{
var tcs = new TaskCompletionSource <object>(descriptor, TaskCreationOptions.RunContinuationsAsynchronously);
// "_ =" to discard 'async/await' compiler warning
_ = AwaitCompletionAsync(task, callback, tcs, descriptor);
return(tcs.Task);
}
private void HandleException(Exception ex, ConsumerDescriptor descriptor)
{
if (ex is AggregateException ae)
{
ae.InnerExceptions.Each(x => Logger.Error(x));
}
else
{
Logger.Error(ex);
}
if (!descriptor.FireForget)
{
throw ex;
}
}
protected internal virtual IEnumerable <object> ResolveParameters(
IComponentContext container,
ConsumerDescriptor descriptor,
CancellationToken cancelToken)
{
foreach (var p in descriptor.Parameters)
{
if (p.ParameterType == typeof(CancellationToken))
{
yield return(cancelToken);
}
else
{
yield return(_resolver.ResolveParameter(p, container));
}
}
}
private async Task AwaitCompletionAsync(
Task task,
AsyncCallback callback,
TaskCompletionSource <object> tcs,
ConsumerDescriptor descriptor)
{
try
{
await task;
tcs.TrySetResult(null);
}
catch (OperationCanceledException ex)
{
tcs.TrySetCanceled(ex.CancellationToken);
}
catch (Exception ex)
{
tcs.TrySetException(ex);
}
finally
{
callback?.Invoke(tcs.Task);
}
}
public void Invoke <TMessage>(ConsumerDescriptor descriptor, IConsumer consumer, ConsumeContext <TMessage> envelope) where TMessage : class
{
var d = descriptor;
var p = descriptor.WithEnvelope ? (object)envelope : envelope.Message;
var fastInvoker = FastInvoker.GetInvoker(d.Method);
if (!d.FireForget && !d.IsAsync)
{
// The all synch case
try
{
InvokeCore();
}
catch (Exception ex)
{
HandleException(ex, d);
}
}
else if (!d.FireForget && d.IsAsync)
{
//// The awaitable Task case
//BeginInvoke((Task)InvokeCore(cancelToken: AsyncRunner.AppShutdownCancellationToken), EndInvoke, d);
// For now we must go with the AsyncRunner, the above call to BeginInvoke (APM > TPL) does not always
// guarantee that the task is awaited and throws exceptions especially when EF is involved.
using (var runner = AsyncRunner.Create())
{
try
{
runner.Run((Task)InvokeCore(cancelToken: AsyncRunner.AppShutdownCancellationToken));
}
catch (Exception ex)
{
HandleException(ex, d);
}
}
}
else if (d.FireForget && !d.IsAsync)
{
// A synch method should be executed async (without awaiting)
AsyncRunner.Run((c, ct, state) => InvokeCore(c, ct), d)
.ContinueWith(t => EndInvoke(t), /*TaskContinuationOptions.OnlyOnFaulted*/ TaskContinuationOptions.None)
.ConfigureAwait(false);
}
else if (d.FireForget && d.IsAsync)
{
// An async (Task) method should be executed without awaiting
AsyncRunner.Run((c, ct) => (Task)InvokeCore(c, ct), d)
.ContinueWith(t => EndInvoke(t), TaskContinuationOptions.OnlyOnFaulted)
.ConfigureAwait(false);
}
object InvokeCore(IComponentContext c = null, CancellationToken cancelToken = default(CancellationToken))
{
if (d.Parameters.Length == 0)
{
// Only one method param: the message!
return(fastInvoker.Invoke(consumer, p));
}
var parameters = new object[d.Parameters.Length + 1];
parameters[0] = p;
int i = 0;
foreach (var obj in ResolveParameters(c, d, cancelToken).ToArray())
{
i++;
parameters[i] = obj;
}
return(fastInvoker.Invoke(consumer, parameters));
}
}
public void Invoke <TMessage>(ConsumerDescriptor descriptor, IConsumer consumer, ConsumeContext <TMessage> envelope) where TMessage : class
{
var d = descriptor;
var p = descriptor.WithEnvelope ? (object)envelope : envelope.Message;
var fastInvoker = FastInvoker.GetInvoker(d.Method);
var items = HttpContext.Current.GetItem("ConsumerInvoker", () => new List <ConsumerDescriptor>());
items.Add(d);
if (!d.FireForget && !d.IsAsync)
{
// The all synch case
try
{
InvokeCore();
}
catch (Exception ex)
{
HandleException(ex, d);
}
}
else if (!d.FireForget && d.IsAsync)
{
// The awaitable Task case
BeginInvoke((Task)InvokeCore(cancelToken: AsyncRunner.AppShutdownCancellationToken), EndInvoke, d);
}
else if (d.FireForget && !d.IsAsync)
{
// A synch method should be executed async (without awaiting)
AsyncRunner.Run((c, ct, state) => InvokeCore(c, ct), d)
.ContinueWith(t => EndInvoke(t), /*TaskContinuationOptions.OnlyOnFaulted*/ TaskContinuationOptions.None)
.ConfigureAwait(false);
}
else if (d.FireForget && d.IsAsync)
{
// An async (Task) method should be executed without awaiting
AsyncRunner.Run((c, ct) => (Task)InvokeCore(c, ct), d)
.ContinueWith(t => EndInvoke(t), TaskContinuationOptions.OnlyOnFaulted)
.ConfigureAwait(false);
}
object InvokeCore(IComponentContext c = null, CancellationToken cancelToken = default(CancellationToken))
{
if (d.Parameters.Length == 0)
{
// Only one method param: the message!
return(fastInvoker.Invoke(consumer, p));
}
var parameters = new object[d.Parameters.Length + 1];
parameters[0] = p;
int i = 0;
foreach (var obj in ResolveParameters(c, d, cancelToken).ToArray())
{
i++;
parameters[i] = obj;
}
return(fastInvoker.Invoke(consumer, parameters));
}
}
