public static async Task <object> DeserializeFromFileAsync(this IAsyncStreamSerializer serializer, Type type, string path, CancellationToken cancellationToken = default)
{
using (var stream = File.OpenRead(path))
{
return(await serializer.DeserializeFromStreamAsync(type, stream, cancellationToken).ConfigureAwait(false));
}
}
protected override async Task <IEnumerable <CacheItem <T> > > GetItemsAsync <T>(IEnumerable <string> blobKeys, string partitionDirectory)
{
partitionDirectory = partitionDirectory ?? _defaultPartitionDirectory;
ArgCheck.NotNull(nameof(partitionDirectory), partitionDirectory);
var utcNow = DateTimeOffset.UtcNow;
// cache hits
var items = new List <CacheItem <T> >();
foreach (var blobKey in blobKeys)
{
var blob = GetBlobReference(blobKey, partitionDirectory);
var exists = await blob.ExistsAsync(_options, new OperationContext()).ConfigureAwait(false);
if (!exists)
{
continue;
}
// load metadata and properties
await blob.FetchAttributesAsync(new AccessCondition(), _options, new OperationContext()).ConfigureAwait(false);
// read expiration
DateTimeOffset?expiration = null;
if (blob.Metadata.TryGetValue(_cacheExpirationMetadataKey, out var expirationString) &&
DateTimeOffset.TryParseExact(expirationString, _dateTimeFormatString, null, DateTimeStyles.None, out var expirationDateTime))
{
if (expirationDateTime <= utcNow)
{
// remove if expired
await blob.DeleteIfExistsAsync(DeleteSnapshotsOption.IncludeSnapshots, new AccessCondition()
{
IfMatchETag = blob.Properties.ETag
}, _options, new OperationContext()).ConfigureAwait(false);
// this one is expired so move on to the next one
continue;
}
// record the expiration for info later
expiration = expirationDateTime;
}
// cache hit...
using (var stream = await blob.OpenReadAsync(new AccessCondition(), _options, new OperationContext()).ConfigureAwait(false))
{
stream.Position = 0;
var item = new CacheItem <T>()
{
Key = blobKey,
Value = await _serializer.DeserializeFromStreamAsync <T>(stream).ConfigureAwait(false),
LastUpdated = blob.Properties.LastModified.GetValueOrDefault(),
Expiration = expiration,
};
items.Add(item);
}
}
return(items);
}
public static async Task <T> DeserializeFromStreamAsync <T>(this IAsyncStreamSerializer serializer, Stream stream, CancellationToken cancellationToken = default)
{
return((T)await serializer.DeserializeFromStreamAsync(typeof(T), stream, cancellationToken).ConfigureAwait(false));
}