/// <summary>
/// Constructs a DbDataJoiner instance
/// </summary>
/// <param name="joinOn">Property path from the root object down to the lookup key</param>
/// <param name="dimTableTarget">Table information of the remote dimension table</param>
/// <param name="option">Option to use for this dataflow</param>
/// <param name="batchSize">The batch size for a batched remote look up</param>
/// <param name="cacheSize">The local cache item count (part of the remote table)</param>
public DbDataJoiner(Expression <Func <TIn, TLookupKey> > joinOn, TargetTable dimTableTarget, DataflowOptions option, int batchSize = 8 * 1024, int cacheSize = 1024 * 1024)
: base(option)
{
m_dimTableTarget = dimTableTarget;
m_batchSize = batchSize;
m_batcher = new BatchBlock <TIn>(batchSize, option.ToGroupingBlockOption()).ToDataflow(option);
m_batcher.Name = "Batcher";
m_lookupNode = new TransformManyDataflow <JoinBatch <TIn>, TIn>(this.JoinBatch, option);
m_lookupNode.Name = "LookupNode";
m_typeAccessor = TypeAccessorManager <TIn> .GetAccessorForTable(dimTableTarget);
m_keyComparer = typeof(TLookupKey) == typeof(byte[])
? (IEqualityComparer <TLookupKey>)((object)new ByteArrayEqualityComparer())
: EqualityComparer <TLookupKey> .Default;
m_rowCache = new RowCache <TLookupKey>(cacheSize, m_keyComparer);
m_logger = Utils.GetNamespaceLogger();
m_joinOnMapping = m_typeAccessor.DbColumnMappings.First(m => m.Host.PropertyInfo == this.ExtractPropertyInfo(joinOn));
var transformer =
new TransformBlock <TIn[], JoinBatch <TIn> >(
array => new JoinBatch <TIn>(array, CacheLookupStrategy.RemoteLookup), option.ToExecutionBlockOption()).ToDataflow(option);
transformer.Name = "ArrayToJoinBatchConverter";
m_batcher.LinkTo(transformer);
transformer.LinkTo(m_lookupNode);
RegisterChild(m_batcher);
RegisterChild(transformer);
RegisterChild(m_lookupNode);
m_dimInserter = new DimTableInserter(this, dimTableTarget, joinOn, option)
{
Name = "DimInserter"
};
var hb = new HeartbeatNode <JoinBatch <TIn> >(option);
m_dimInserter.RegisterDependency(m_lookupNode);
m_dimInserter.LinkTo(hb);
hb.LinkTo(m_lookupNode);
RegisterChild(m_dimInserter);
RegisterChild(hb);
RegisterChildRing(transformer.CompletionTask, m_lookupNode, m_dimInserter, hb);
}
public CircularFlow(DataflowOptions dataflowOptions) : base(dataflowOptions)
{
//a no-op node to demonstrate the usage of preTask param in RegisterChildRing
_buffer = new BufferBlock <int>().ToDataflow(name: "NoOpBuffer");
var heater = new TransformManyDataflow <int, int>(async i =>
{
await Task.Delay(200);
Console.WriteLine("Heated to {0}", i + 1);
return(new [] { i + 1 });
}, dataflowOptions);
heater.Name = "Heater";
var cooler = new TransformManyDataflow <int, int>(async i =>
{
await Task.Delay(200);
int cooled = i - 2;
Console.WriteLine("Cooled to {0}", cooled);
if (cooled < 0) //time to stop
{
return(Enumerable.Empty <int>());
}
return(new [] { cooled });
}, dataflowOptions);
cooler.Name = "Cooler";
var heartbeat = new HeartbeatNode <int>(dataflowOptions)
{
Name = "HeartBeat"
};
_buffer.LinkTo(heater);
//circular
heater.LinkTo(cooler);
cooler.LinkTo(heartbeat);
heartbeat.LinkTo(heater);
RegisterChildren(_buffer, heater, cooler, heartbeat);
//ring registration
RegisterChildRing(_buffer.Completion, heater, cooler, heartbeat);
}
