protected virtual async Task <IList <ImageChange> > GetChangeFiles(ThumbnailTask task, DateTime?changedSince, ICancellationToken token)
{
var options = await GetOptionsCollection();
var cacheKey = CacheKey.With(GetType(), "GetChangeFiles", task.WorkPath, changedSince?.ToString(), string.Join(":", options.Select(x => x.FileSuffix)));
return(await _platformMemoryCache.GetOrCreateExclusiveAsync(cacheKey, async (cacheEntry) =>
{
cacheEntry.AddExpirationToken(BlobChangesCacheRegion.CreateChangeToken(task, changedSince));
var allBlobInfos = await ReadBlobFolderAsync(task.WorkPath, token);
var orignalBlobInfos = GetOriginalItems(allBlobInfos, options.Select(x => x.FileSuffix).ToList());
var result = new List <ImageChange>();
foreach (var blobInfo in orignalBlobInfos)
{
token?.ThrowIfCancellationRequested();
var imageChange = new ImageChange
{
Name = blobInfo.Name,
Url = blobInfo.Url,
ModifiedDate = blobInfo.ModifiedDate,
ChangeState = !changedSince.HasValue ? EntryState.Added : GetItemState(blobInfo, changedSince, task.ThumbnailOptions)
};
result.Add(imageChange);
}
return result.Where(x => x.ChangeState != EntryState.Unchanged).ToList();
}));
}