/// <summary>
/// Inserts resource into file with key.
/// </summary>
/// <param name="key">Cache key.</param>
/// <param name="callback">
/// Callback that writes to an output stream.
/// </param>
/// <returns>A sequence of bytes.</returns>
public IBinaryResource Insert(ICacheKey key, IWriterCallback callback)
{
// Write to a temp file, then move it into place.
// This allows more parallelism when writing files.
SettableCacheEvent cacheEvent = SettableCacheEvent.Obtain().SetCacheKey(key);
_cacheEventListener.OnWriteAttempt(cacheEvent);
string resourceId;
lock (_lock)
{
// For multiple resource ids associated with the same image,
// we only write one file
resourceId = CacheKeyUtil.GetFirstResourceId(key);
}
cacheEvent.SetResourceId(resourceId);
try
{
// Getting the file is synchronized
IInserter inserter = StartInsert(resourceId, key);
try
{
inserter.WriteData(callback, key);
// Committing the file is synchronized
IBinaryResource resource = EndInsert(inserter, key, resourceId);
cacheEvent.SetItemSize(resource.GetSize())
.SetCacheSize(_cacheStats.Size);
_cacheEventListener.OnWriteSuccess(cacheEvent);
return(resource);
}
finally
{
if (!inserter.CleanUp())
{
Debug.WriteLine("Failed to delete temp file");
}
}
}
catch (IOException ioe)
{
cacheEvent.SetException(ioe);
_cacheEventListener.OnWriteException(cacheEvent);
Debug.WriteLine("Failed inserting a file into the cache");
throw;
}
finally
{
cacheEvent.Recycle();
}
}
private static void WriteToResource(
IInserter inserter,
byte[] content)
{
inserter.WriteData(
new WriterCallbackImpl(
os =>
{
os.Write(content, 0, content.Length);
}),
null);
}