public async Task <HttpResponseMessage> GetNewsAsync()
{
using (var cts = new CancellationTokenSource())
{
RunningTasks.Add(RemoteRequestAsync(redditApi.GetApi(Priority.UserInitiated).GetNews(cts.Token)).Id, cts);
return(await RemoteRequestAsync(redditApi.GetApi(Priority.UserInitiated).GetNews(cts.Token)));
}
}
public async Task <HttpResponseMessage> GetMakeUpsAsync(string brand)
{
using (var cts = new CancellationTokenSource())
{
Task <HttpResponseMessage> task = RemoteRequestAsync(makeUpApi.GetApi(Priority.UserInitiated).GetMakeUps(brand));
RunningTasks.Add(task.Id, cts);
return(await task);
}
}
public async Task <int> AddMakeupLocalDataAsync(List <MakeUpModel> makeUpModelList)
{
using var cts = new CancellationTokenSource();
Task <int> task = makeUpApi.InsertAll(AutoMapper.Map <List <MakeUp> >(makeUpModelList));
RunningTasks.Add(task.Id, cts);
return(await task);
}
public async Task <List <MakeUpModel> > GetMakeupLocalDataAsync()
{
using (var cts = new CancellationTokenSource())
{
Task <List <MakeUp> > task = makeUpApi.Get();
RunningTasks.Add(task.Id, cts);
var makeUpModels = Task.Run(() => AutoMapper.Map <List <MakeUpModel> >(task.Result));
RunningTasks.Add(makeUpModels.Id, cts);
return(await makeUpModels);
}
}
protected async Task RunImageLoadingTaskAsync(PendingTask pendingTask)
{
var key = pendingTask.ImageLoadingTask.Key;
lock (_pendingTasksLock)
{
if (RunningTasks.ContainsKey(key))
return;
RunningTasks.Add(key, pendingTask);
Interlocked.Increment(ref _statsTotalRunning);
}
try
{
if (Configuration.VerbosePerformanceLogging)
{
LogSchedulerStats();
var stopwatch = Stopwatch.StartNew();
await Task.Run(pendingTask.ImageLoadingTask.RunAsync).ConfigureAwait(false);
stopwatch.Stop();
Logger.Debug(
string.Format(
"[PERFORMANCE] RunAsync - NetManagedThreadId: {0}, NativeThreadId: {1}, Execution: {2} ms, Key: {3}",
Performance.GetCurrentManagedThreadId(),
Performance.GetCurrentSystemThreadId(),
stopwatch.Elapsed.Milliseconds,
key));
}
else
{
await Task.Run(pendingTask.ImageLoadingTask.RunAsync).ConfigureAwait(false);
}
}
finally
{
lock (_pendingTasksLock)
{
RunningTasks.Remove(key);
}
pendingTask?.ImageLoadingTask?.Dispose();
await TakeFromPendingTasksAndRunAsync().ConfigureAwait(false);
}
}
public async Task <List <MakeUpModel> > GetMakeupLocalUsingEFDataAsync()
{
using (var cts = new CancellationTokenSource())
{
var makeUp = new MakeUp()
{
Brand = "xxxxx",
Category = "xxxxxxx"
};
MakeUp value = UnitOfWork.GenericHandler <MakeUp>().Insert(makeUp);
UnitOfWork.Save();
Task <List <MakeUp> > task = makeUpApi.Get();
RunningTasks.Add(task.Id, cts);
var makeUpModels = Task.Run(() => AutoMapper.Map <List <MakeUpModel> >(task.Result));
RunningTasks.Add(makeUpModels.Id, cts);
return(await makeUpModels);
}
}
protected async Task TakeFromPendingTasksAndRunAsync()
{
if (PendingTasks.Count == 0)
{
return;
}
Dictionary <string, IImageLoaderTask> tasksToRun = null;
int preloadOrUrlTasksCount = 0;
int urlTasksCount = 0;
int preloadTasksCount = 0;
lock (_lock)
{
if (RunningTasks.Count >= MaxParallelTasks)
{
urlTasksCount = RunningTasks.Count(v => v.Value != null && (!v.Value.Parameters.Preload && v.Value.Parameters.Source == ImageSource.Url));
preloadTasksCount = RunningTasks.Count(v => v.Value != null && v.Value.Parameters.Preload);
preloadOrUrlTasksCount = preloadTasksCount + urlTasksCount;
if (preloadOrUrlTasksCount == 0 || preloadOrUrlTasksCount != MaxParallelTasks)
{
return;
}
// Allow only half of MaxParallelTasks as additional allowed tasks when preloading occurs to prevent starvation
if (RunningTasks.Count - Math.Max(1, Math.Min(preloadOrUrlTasksCount, MaxParallelTasks / 2)) >= MaxParallelTasks)
{
return;
}
}
int numberOfTasks = MaxParallelTasks - RunningTasks.Count + Math.Min(preloadOrUrlTasksCount, MaxParallelTasks / 2);
tasksToRun = new Dictionary <string, IImageLoaderTask>();
IImageLoaderTask task = null;
while (tasksToRun.Count < numberOfTasks && PendingTasks.TryDequeue(out task))
{
if (task == null || task.IsCancelled || task.IsCompleted)
{
continue;
}
// We don't want to load, at the same time, images that have same key or same raw key at the same time
// This way we prevent concurrent downloads and benefit from caches
string rawKey = task.KeyRaw;
if (RunningTasks.ContainsKey(rawKey) || tasksToRun.ContainsKey(rawKey))
{
SimilarTasks.Add(task);
continue;
}
if (preloadOrUrlTasksCount != 0)
{
if (!task.Parameters.Preload && (urlTasksCount == 0 || task.Parameters.Source != ImageSource.Url))
{
tasksToRun.Add(rawKey, task);
}
else
{
Enqueue(task);
break;
}
}
else
{
tasksToRun.Add(rawKey, task);
}
}
foreach (var item in tasksToRun)
{
RunningTasks.Add(item.Key, item.Value);
Interlocked.Increment(ref _statsTotalRunning);
}
}
if (tasksToRun != null && tasksToRun.Count > 0)
{
var tasks = tasksToRun.Select(p => RunImageLoadingTaskAsync(p.Value));
await Task.WhenAll(tasks).ConfigureAwait(false);
}
}
/// <summary>
/// Asynchronously runs <paramref name="delegateFunction"/> for every item in the given collection
/// </summary>
/// <typeparam name="T">Type of the collection item</typeparam>
/// <param name="delegateFunction">The function to asynchronously run</param>
/// <param name="collection">The collection to be enumerated</param>
/// <exception cref="InvalidOperationException">Thrown if execution starts before the end of another operation</exception>
public async Task RunForEach <T>(IEnumerable <T> collection, ForEachItemAsync <T> delegateFunction)
{
if (RunningTasks.Count > 0)
{
throw new InvalidOperationException(Properties.Resources.AsyncFor_ErrorNoConcurrentExecution);
}
var exceptions = new List <Exception>();
var taskItemQueue = new Queue <T>();
foreach (var item in collection)
{
taskItemQueue.Enqueue(item);
}
TotalTasks = taskItemQueue.Count;
// While there's either more tasks to start or while there's still tasks running
while (taskItemQueue.Count > 0 || (taskItemQueue.Count == 0 && RunningTasks.Count > 0))
{
if ((BatchSize < 1 || RunningTasks.Count < BatchSize) && taskItemQueue.Count > 0)
{
// We can run more tasks
// Get the next task item to run
var item = taskItemQueue.Dequeue(); // The item in Collection to process
// Start the task
var tTask = Task.Run(async() =>
{
await delegateFunction(item).ConfigureAwait(false);
IncrementCompletedTasks();
});
// Either wait for it or move on
if (RunSynchronously)
{
await tTask.ConfigureAwait(false);
}
else
{
RunningTasks.Add(tTask);
}
}
else
{
if (RunningTasks.Count > 0)
{
// We can't start any more tasks, so we have to wait on one.
await Task.WhenAny(RunningTasks).ConfigureAwait(false);
// Remove completed tasks
for (var count = RunningTasks.Count - 1; count >= 0; count--)
{
if (RunningTasks[count].Exception != null)
{
var ex = RunningTasks[count].Exception;
if (ex is AggregateException aggregateEx && aggregateEx.InnerExceptions.Count == 1)
{
exceptions.Add(aggregateEx.InnerExceptions.First());
}
else
{
exceptions.Add(RunningTasks[count].Exception);
}
RunningTasks.RemoveAt(count);
}
else if (RunningTasks[count].IsCompleted)
{
RunningTasks.RemoveAt(count);
}
}
}
protected async Task TakeFromPendingTasksAndRunAsync()
{
if (PendingTasks.Count == 0)
{
return;
}
Dictionary <string, IImageLoaderTask>?tasksToRun = null;
int urlTasksCount = 0;
lock (_lock)
{
if (RunningTasks.Count >= MaxParallelTasks)
{
urlTasksCount = RunningTasks.Count(v => v.Value != null && v.Value.ImageSource.Source is UriSource);
if (urlTasksCount == 0 || urlTasksCount != MaxParallelTasks)
{
return;
}
// Allow only half of MaxParallelTasks as additional allowed tasks when preloading occurs to prevent starvation
if (RunningTasks.Count - Math.Max(1, Math.Min(urlTasksCount, MaxParallelTasks / 2)) >= MaxParallelTasks)
{
return;
}
}
int numberOfTasks = MaxParallelTasks - RunningTasks.Count + Math.Min(urlTasksCount, MaxParallelTasks / 2);
tasksToRun = new Dictionary <string, IImageLoaderTask>();
while (tasksToRun.Count < numberOfTasks && PendingTasks.TryDequeue(out IImageLoaderTask? task))
{
if (task == null || task.IsCancelled || task.IsCompleted)
{
continue;
}
// We don't want to load, at the same time, images that have same key or same raw key at the same time
// This way we prevent concurrent downloads and benefit from caches
string rawKey = task.KeyRaw;
if (RunningTasks.ContainsKey(rawKey) || tasksToRun.ContainsKey(rawKey))
{
SimilarTasks.Add(task);
continue;
}
if (urlTasksCount != 0)
{
if (!(task.ImageSource.Source is UriSource))
{
tasksToRun.Add(rawKey, task);
}
else
{
Enqueue(task);
break;
}
}
else
{
tasksToRun.Add(rawKey, task);
}
}
foreach (var item in tasksToRun)
{
RunningTasks.Add(item.Key, item.Value);
Interlocked.Increment(ref _statsTotalRunning);
}
}
if (tasksToRun != null && tasksToRun.Count > 0)
{
var tasks = tasksToRun.Select(async p =>
{
await Task.Factory.StartNew(async() =>
{
try
{
await RunImageLoadingTaskAsync(p.Value).ConfigureAwait(false);
}
catch (Exception ex)
{
_imageLoader.Logger?.Error("TakeFromPendingTasksAndRun exception", ex);
}
}, CancellationToken.None, TaskCreationOptions.PreferFairness | TaskCreationOptions.DenyChildAttach | TaskCreationOptions.HideScheduler, TaskScheduler.Default).ConfigureAwait(false);
});
await Task.WhenAll(tasks).ConfigureAwait(false);
}
}
public void SubmitTask(Task task)
{
RunningTasks.Add(task);
}