/// <summary>
/// Retrieve a read-only stream over an object that has been stored.
/// </summary>
/// <param name="key">The object key.</param>
/// <param name="callbacks">CallbackMethods object containing callback methods.</param>
/// <returns>Read-only stream.</returns>
public DedupeStream GetStream(string key, DedupeCallbacks callbacks)
{
if (String.IsNullOrEmpty(key))
{
throw new ArgumentNullException(nameof(key));
}
if (callbacks == null)
{
throw new ArgumentNullException(nameof(callbacks));
}
if (callbacks.ReadChunk == null)
{
throw new ArgumentException("ReadChunk callback must be specified.");
}
key = DedupeCommon.SanitizeString(key);
DedupeObject md = GetMetadata(key);
if (md == null)
{
throw new KeyNotFoundException("Object key '" + key + "' not found.");
}
return(new DedupeStream(md, _Database, callbacks));
}
/// <summary>
/// Retrieve an object from the deduplication index.
/// This method will use the callbacks supplied in the method signature.
/// </summary>
/// <param name="key">The object key.</param>
/// <param name="callbacks">CallbackMethods object containing callback methods.</param>
/// <returns>Object data.</returns>
public DedupeObject Get(string key, DedupeCallbacks callbacks)
{
if (String.IsNullOrEmpty(key))
{
throw new ArgumentNullException(nameof(key));
}
if (callbacks == null)
{
throw new ArgumentNullException(nameof(callbacks));
}
if (callbacks.ReadChunk == null)
{
throw new ArgumentException("ReadChunk callback must be specified.");
}
key = DedupeCommon.SanitizeString(key);
DedupeObject md = _Database.GetObjectMetadata(key);
if (md == null)
{
throw new KeyNotFoundException("Object key '" + key + "' not found.");
}
if (md.Chunks == null || md.Chunks.Count < 1)
{
throw new IOException("No chunks returned for object key '" + key + "'.");
}
MemoryStream stream = new MemoryStream();
long contentLength = 0;
foreach (DedupeObjectMap curr in md.ObjectMap)
{
byte[] chunkData = callbacks.ReadChunk(curr.ChunkKey);
if (chunkData == null || chunkData.Length < 1)
{
throw new IOException("Unable to read chunk '" + curr.ChunkKey + "'.");
}
stream.Write(chunkData, 0, chunkData.Length);
contentLength += chunkData.Length;
}
if (contentLength > 0)
{
stream.Seek(0, SeekOrigin.Begin);
}
md.DataStream = stream;
return(md);
}
/// <summary>
/// Retrieve an object from the deduplication index.
/// </summary>
/// <param name="key">The object key.</param>
/// <param name="data">Object data.</param>
/// <returns>True if successful.</returns>
public bool TryGet(string key, out DedupeObject data)
{
if (String.IsNullOrEmpty(key))
{
throw new ArgumentNullException(nameof(key));
}
data = null;
try
{
data = Get(key, Callbacks);
return(true);
}
catch (Exception)
{
return(false);
}
}
internal DedupeStream(DedupeObject md, DbProvider db, DedupeCallbacks callbacks)
{
if (md == null)
{
throw new ArgumentNullException(nameof(md));
}
if (db == null)
{
throw new ArgumentNullException(nameof(db));
}
if (callbacks == null)
{
throw new ArgumentNullException(nameof(callbacks));
}
_Metadata = md;
_Database = db;
_Callbacks = callbacks;
}