DispatchSharp

https://www.nuget.org/packages/DispatchSharp/

A library to make multi-threaded dispatch code more testable.

Models a job dispatch pattern and provides both threaded and non threaded implementations.

Getting Started

Doing a batch of work:

void DoBatch(IEnumerable<object> workToDo) {
	var dispatcher = Dispatch<object>.CreateDefaultMultiThreaded("MyTask");

	dispatcher.AddConsumer(MyWorkMethod);
	dispatcher.Start();
	dispatcher.AddWork(workToDo);
	dispatcher.WaitForEmptyQueueAndStop();	// only call this if you're not filling the queue from elsewhere
}

or

Dispatch<int>.ProcessBatch("BatchRequests", Enumerable.Range(0, times).ToArray(), i => {
        . . .
    },
    threadCount,
    ex => {
        Console.WriteLine("Error: " + ex.Message);
    }
);

Handling long running incoming jobs:

dispatcher = Dispatch<object>.CreateDefaultMultiThreaded("MyService");
dispatcher.AddConsumer(MyWorkMethod);
dispatcher.Start();
.
.
.
dispatcher.AddWork(...);

Using a polling method to handle incoming jobs in a long-running process:

var dispatcher = Dispatch<object>.PollAndProcess("MyService", myPollingSource);
dispatcher.AddConsumer(MyWorkMethod);
dispatcher.Start();

with a method defined like

void MyWorkMethod(object obj)
{
	. . .
}

Multiple consumers

A dispatcher can be given multiple consumers. In this case, each consumer will get given each work item added.

So with

dispatcher = Dispatch<string>.CreateDefaultMultiThreaded("MyService");
dispatcher.AddConsumer(wi=> Console.Write($" Consumer 1, work item {wi};"));
dispatcher.AddConsumer(wi=> Console.Write($" Consumer 2, work item {wi};"));
dispatcher.AddConsumer(wi=> Console.Write($" Consumer 3, work item {wi};"));
dispatcher.Start();

dispatcher.AddWork("1");
Console.WriteLine();
dispatcher.AddWork("2");
Console.WriteLine();
dispatcher.AddWork("3");
Console.WriteLine();

We should get output similar to

 Consumer 1, work item 1; Consumer 2, work item 1; Consumer 3, work item 1;
 Consumer 1, work item 2; Consumer 2, work item 2; Consumer 3, work item 2;
 Consumer 1, work item 3; Consumer 2, work item 3; Consumer 3, work item 3;

Parallelism Modes

By default, work items are processed in parallel, with each consumer being run in sequential order ('work parallel').

If you need to have each work item handled strictly in-order, but each consumer can be run in parallel, use the 'task parallel' mode:

dispatcher = Dispatch<string>.CreateTaskParallelMultiThreaded("MyService");
dispatcher.AddConsumer(wi=> Console.Write($" Consumer 1, work item {wi};"));
dispatcher.AddConsumer(wi=> Console.Write($" Consumer 2, work item {wi};"));
dispatcher.AddConsumer(wi=> Console.Write($" Consumer 3, work item {wi};"));
dispatcher.Start();