BufferBlock deadlock with OutputAvailableAsync after TryReceiveAll

Answer 1

Alas, it's the end of September 2015, and although i3arnon fixed the error it is not solved in the version that was released two days after the error was fixed: Microsoft TPL Dataflow version 4.5.24.

However IReceivableSourceBlock.TryReceive(...) works correctly. An extension method will solve the problem. After a new release of TPL Dataflow it will be easy to change the extension method.

/// 

/// This extension method returns all available items in the IReceivableSourceBlock
/// or an empty sequence if nothing is available. The functin does not wait.
/// 
/// The type of items stored in the IReceivableSourceBlock
/// the source where the items should be extracted from 
/// The IList with the received items. Empty if no items were available
public static IList TryReceiveAllEx(this IReceivableSourceBlock buffer)
{
    /* Microsoft TPL Dataflow version 4.5.24 contains a bug in TryReceiveAll
     * Hence this function uses TryReceive until nothing is available anymore
     * */
    IList receivedItems = new List();
    T receivedItem = default(T);
    while (buffer.TryReceive(out receivedItem))
    {
        receivedItems.Add(receivedItem);
    }
    return receivedItems;
}

usage:

while (await this.bufferBlock.OutputAvailableAsync())
{
    // some data available
    var receivedItems = this.bufferBlock.TryReceiveAllEx();
    if (receivedItems.Any())
    {
        ProcessReceivedItems(bufferBlock);
    }
}