public void StoreBytesForExistingStreams(Guid dataIdentifier, byte[] fileData, ICustomMetaData customMetaData, AddFileBehaviour addFileBehaviour)
{
#region Preconditions and initialization ...
if (fileData.LongLength > fileData.Length)
{
throw new Exception("NFileStorage is (currently) limited to a max length of 32bit (about 4.294.967.296 bytes)");
}
//
// first check the behaviour conditions
//
switch (addFileBehaviour)
{
case AddFileBehaviour.SkipWhenAlreadyExists:
if (Exists(dataIdentifier, StreamStateBehaviour.UseExistingStream))
{
return;
}
break;
case AddFileBehaviour.ThrowExceptionWhenAlreadyExists:
if (Exists(dataIdentifier, StreamStateBehaviour.UseExistingStream))
{
throw new Exception(string.Format("File {0} already exists", dataIdentifier));
}
break;
case AddFileBehaviour.OverrideWhenAlreadyExists:
if (Exists(dataIdentifier, StreamStateBehaviour.UseExistingStream))
{
DeleteDataIdentifier(dataIdentifier, DeleteFileBehaviour.ThrowExceptionWhenNotExists,
StreamStateBehaviour.UseExistingStream);
}
break;
default:
throw new NotSupportedException(string.Format("Unsupported behaviour; {0}", addFileBehaviour));
}
#endregion
bool supportsMetaData = SupportsFeature(FileStorageFeatureEnum.StoreMetaData);
long dataOffset = DataStream.Length;
int dataLength = fileData.Length;
Int64 metaDataOffsetInFileFromBegin;
if (supportsMetaData)
{
if (customMetaData == null)
{
customMetaData = new EmptyCustomMetaData();
}
metaDataOffsetInFileFromBegin = dataOffset + DataFileDataStructSize + dataLength;
}
else
{
metaDataOffsetInFileFromBegin = 0;
}
// create a new struct with offsets 0 for each index in guid
var newFileStruct = new DataFileDataStruct
{
DataIdentification = dataIdentifier,
BinaryDataSizeInBytes = dataLength,
DataStateEnumID = 0,
MetaDataOffsetInFileFromBegin = metaDataOffsetInFileFromBegin,
ReservedB = 0
};
#region Store the information in the data file
#region Store struct in data file
StoreStruct(dataOffset, newFileStruct);
#endregion
#region Store actual data in data file
//
// the stream is intentionally left open
//
var bufferedDataFileStream = new BufferedStream(DataStream);
// write the actual data
bufferedDataFileStream.Write(fileData, 0, dataLength);
// flush, to ensure we don't have bytes in the queue when we close the file
bufferedDataFileStream.Flush();
#endregion
#region Store meta data in data file
if (supportsMetaData)
{
//
// use the DynamiteXML feature to store metadata
//
var metaDataContainer = new MetaDataContainer(customMetaData, DateTime.UtcNow, dataLength);
string metaDataString = DynamiteXmlLogic.Serialize(metaDataContainer);
byte[] metaDataBytes = Encoding.UTF8.GetBytes(metaDataString);
//
// write the length of the bytes of the metadata
//
var binaryWriter = new BinaryWriter(DataStream);
binaryWriter.Write(metaDataBytes.Length);
bufferedDataFileStream.Write(metaDataBytes, 0, metaDataBytes.Length);
// flush, to ensure we don't have bytes in the queue when we close the file
bufferedDataFileStream.Flush();
}
#endregion
#endregion
#region Store the information in the index file
//
// derive the build index behaviour from the add file behaviour
//
BuildIndexBehaviour buildIndexBehaviour;
switch (addFileBehaviour)
{
case AddFileBehaviour.ThrowExceptionWhenAlreadyExists:
buildIndexBehaviour = BuildIndexBehaviour.ThrowExceptionWhenIndexAlreadyExists;
break;
case AddFileBehaviour.SkipWhenAlreadyExists:
//
// this should have been intercepted before, should be impossible
//
buildIndexBehaviour = BuildIndexBehaviour.ThrowExceptionWhenIndexAlreadyExists;
break;
case AddFileBehaviour.OverrideWhenAlreadyExists:
buildIndexBehaviour = BuildIndexBehaviour.OverrideWhenAlreadyExists;
break;
default:
throw new NotSupportedException(string.Format("Unexpected addFileBehaviour {0}", addFileBehaviour));
}
// we update the index file
BuildIndex(dataIdentifier, dataOffset, buildIndexBehaviour, StreamStateBehaviour.UseExistingStream);
#endregion
}
private void StoreStruct(Int64 offsetInFileFromBegin, DataFileDataStruct fileStruct)
{
// point to the end of the file
DataStream.Seek(offsetInFileFromBegin, SeekOrigin.Begin);
// write the struct
var binaryWriter = new BinaryWriter(DataStream);
binaryWriter.Write(fileStruct.DataIdentification.ToByteArray());
binaryWriter.Write(fileStruct.DataStateEnumID);
binaryWriter.Write(fileStruct.BinaryDataSizeInBytes);
binaryWriter.Write(fileStruct.MetaDataOffsetInFileFromBegin);
binaryWriter.Write(fileStruct.ReservedB);
}
