Queue of async tasks with throttling which supports muti-threading

Question

I need to implement a library to request vk.com API. The problem is that API supports only 3 requests per second. I would like to have API asynchronous.

Answer 1

You can use this as Generic

public TaskThrottle(int maxTasksToRunInParallel)
{
    _semaphore = new SemaphoreSlim(maxTasksToRunInParallel);
}

public void TaskThrottler(IEnumerable> tasks, int timeoutInMilliseconds, CancellationToken cancellationToken = default(CancellationToken)) where T : class
{
    // Get Tasks as List
    var taskList = tasks as IList> ?? tasks.ToList();
    var postTasks = new List>();

    // When the first task completed, it will flag 
    taskList.ForEach(x =>
    {
        postTasks.Add(x.ContinueWith(y => _semaphore.Release(), cancellationToken));
    });

    taskList.ForEach(x =>
    {
        // Wait for open slot 
        _semaphore.Wait(timeoutInMilliseconds, cancellationToken);
        cancellationToken.ThrowIfCancellationRequested();
        x.Start();
    });

    Task.WaitAll(taskList.ToArray(), cancellationToken);
}