/// <summary>
/// Invoke underlying batch operation with aggregating.
/// </summary>
public async Task <IReadOnlyList <TResult> > InvokeAsync(IReadOnlyList <TArg> args)
{
ProxyItem <TArg, TResult> proxyItem;
int startIndex;
if (!TryAggregate(args, out proxyItem, out startIndex))
{
proxyItem = new ProxyItem <TArg, TResult>(args);
_aggregatableQueue.TryAdd(proxyItem, null);
startIndex = 0;
_pool.Queue(async() =>
{
object _;
_aggregatableQueue.TryRemove(proxyItem, out _);
proxyItem.Close();
try
{
proxyItem.TaskCompletionSource.SetResult(await _func(proxyItem.Args));
}
catch (Exception ex)
{
proxyItem.TaskCompletionSource.SetException(ex);
}
});
}
var results = await proxyItem.TaskCompletionSource.Task;
await Task.Yield();
return((IReadOnlyList <TResult>) new Segment <TResult>(results, startIndex, args.Count));
}
private bool TryAggregate(
IReadOnlyList <TArg> args,
out ProxyItem <TArg, TResult> proxyItem,
out int startIndex)
{
foreach (var item in _aggregatableQueue)
{
var current = item.Key;
startIndex = current.TryAggregate(args, _rules);
if (startIndex != -1)
{
proxyItem = current;
return(true);
}
}
// unable to aggregate
proxyItem = null;
startIndex = -1;
return(false);
}
