/// <summary>
/// Validates the source BLOB is valid.
/// </summary>
/// <returns>The resultant tuple.</returns>
private async Task <Tuple <bool, BlobToS3Response, CloudBlockBlob> > Validate()
{
BlobToS3Response blobToS3Response = null;
CloudBlobContainer cloudBlobContainer = this.blobToS3Request.BlobClient.GetContainerReference(this.blobToS3Request.SourceBlobContainer);
if (!await cloudBlobContainer.ExistsAsync())
{
blobToS3Response = new BlobToS3Response
{
IsSuccess = false,
Message = ContainerNotExists
};
return(new Tuple <bool, BlobToS3Response, CloudBlockBlob>(false, blobToS3Response, null));
}
CloudBlockBlob cloudBlockBlob = cloudBlobContainer.GetBlockBlobReference(this.blobToS3Request.SourceBlob);
if (await cloudBlockBlob.ExistsAsync())
{
return(new Tuple <bool, BlobToS3Response, CloudBlockBlob>(true, null, cloudBlockBlob));
}
blobToS3Response = new BlobToS3Response
{
IsSuccess = false,
Message = BlobNotExists
};
return(new Tuple <bool, BlobToS3Response, CloudBlockBlob>(false, blobToS3Response, null));
}
/// <summary>
/// Copies BLOB to S3.
/// </summary>
/// <returns>The BLOB to S3 response.</returns>
public async Task <BlobToS3Response> CopyFromBlobToS3Async()
{
BlobToS3Response blobToS3Response = new BlobToS3Response();
var validation = await this.Validate();
if (!validation.Item1)
{
return(validation.Item2);
}
var sourceBlob = validation.Item3;
await sourceBlob.FetchAttributesAsync();
var remainingBytes = sourceBlob.Properties.Length;
long readPosition = 0; // To be used offset / position from where to start reading from BLOB.
InitiateMultipartUploadRequest initiateMultipartUploadRequest = new InitiateMultipartUploadRequest
{
BucketName = this.blobToS3Request.TargetS3Bucket,
Key = this.blobToS3Request.TargetS3File
};
// Will use UploadId from this response.
InitiateMultipartUploadResponse initiateMultipartUploadResponse = this.blobToS3Request.S3Client.InitiateMultipartUpload(initiateMultipartUploadRequest);
List <UploadPartResponse> uploadPartResponses = new List <UploadPartResponse>();
try
{
int partCounter = 0; // To increment on each read of parts and use it as part number.
var sha256 = new SHA256Managed();
while (remainingBytes > 0)
{
// Determine the size when final block reached as it might be less than Part size.
// Will be PartSize except final block.
long bytesToCopy = Math.Min(PartSize, remainingBytes);
using (MemoryStream memoryStream = new MemoryStream())
{
// To download part from BLOB.
await sourceBlob.DownloadRangeToStreamAsync(memoryStream, readPosition, bytesToCopy).ConfigureAwait(false);
memoryStream.Position = 0;
partCounter++;
UploadPartRequest uploadRequest = new UploadPartRequest
{
BucketName = this.blobToS3Request.TargetS3Bucket,
Key = this.blobToS3Request.TargetS3File,
UploadId = initiateMultipartUploadResponse.UploadId,
PartNumber = partCounter,
PartSize = bytesToCopy,
InputStream = memoryStream
};
UploadPartResponse uploadPartResponse = this.blobToS3Request.S3Client.UploadPart(uploadRequest);
uploadPartResponses.Add(uploadPartResponse);
remainingBytes -= bytesToCopy;
readPosition += bytesToCopy;
// $"Uploaded part with part number {partCounter}, size {bytesToCopy}bytes and remaining {remainingBytes}bytes to read.")
// Calculate the checksum value.
if (remainingBytes <= 0)
{
sha256.TransformFinalBlock(memoryStream.ToArray(), 0, (int)bytesToCopy);
}
else
{
byte[] bytesToSend = memoryStream.ToArray();
sha256.TransformBlock(bytesToSend, 0, (int)bytesToCopy, bytesToSend, 0);
}
}
}
blobToS3Response.Sha256CheckSum = BitConverter.ToString(sha256.Hash).Replace("-", string.Empty);
CompleteMultipartUploadRequest completeMultipartUploadRequest = new CompleteMultipartUploadRequest
{
BucketName = this.blobToS3Request.TargetS3Bucket,
Key = this.blobToS3Request.TargetS3File,
UploadId = initiateMultipartUploadResponse.UploadId
};
completeMultipartUploadRequest.AddPartETags(uploadPartResponses);
CompleteMultipartUploadResponse completeMultipartUploadResponse = await this.blobToS3Request.S3Client.CompleteMultipartUploadAsync(completeMultipartUploadRequest).ConfigureAwait(false);
blobToS3Response.IsSuccess = true;
blobToS3Response.S3Path = completeMultipartUploadResponse.Location;
}
catch (Exception exception)
{
blobToS3Response.IsSuccess = false;
blobToS3Response.Message = exception.Message;
AbortMultipartUploadRequest abortMultipartUploadRequest = new AbortMultipartUploadRequest
{
BucketName = this.blobToS3Request.TargetS3Bucket,
Key = this.blobToS3Request.TargetS3File,
UploadId = initiateMultipartUploadResponse.UploadId
};
await this.blobToS3Request.S3Client.AbortMultipartUploadAsync(abortMultipartUploadRequest).ConfigureAwait(false);
}
return(blobToS3Response);
}
