awaitable Task based queue

Question

I\'m wondering if there exists an implementation/wrapper for ConcurrentQueue, similar to BlockingCollection where taking from the collection does not block, but is instead a

Answer 1

Well 8 years later I hit this very question and was about to implement the MS AsyncQueue class found in nuget package/namespace: Microsoft.VisualStudio.Threading

Thanks to @Theodor Zoulias for mentioning this api may be outdated and the DataFlow lib would be a good alternative.

So I edited my AsyncQueue<> implementation to use BufferBlock<>. Almost the same but works better.

I use this in an AspNet Core background thread and it runs fully async.

protected async Task MyRun()
{
    BufferBlock queue = new BufferBlock();
    Task enqueueTask = StartDataIteration(queue);

    while (await queue.OutputAvailableAsync())
    {
        var myObj = queue.Receive();
        // do something with myObj
    }

}

public async Task StartDataIteration(BufferBlock queue)
{
    var cursor = await RunQuery();
    while(await cursor.Next()) { 
        queue.Post(cursor.Current);
    }
    queue.Complete(); // <<< signals the consumer when queue.Count reaches 0
}

I found that using the queue.OutputAvailableAsync() fixed the issue that I had with AsyncQueue<> -- trying to determine when the queue was complete and not having to inspect the dequeue task.