I have a 2GB file in blob storage and am building a console application that will download this file into a desktop. Requirement is to split into 100MB chunks and append a number into the filename. I do not need to re-combine those files again. What I need is only the chunks of files.
I currently have this code from Azure download blob part
But I cannot figure out how to stop downloading when the file size is already 100MB and create a new one.
Any help will be appreciated.
Update: Here is my code
CloudStorageAccount account = CloudStorageAccount.Parse(connectionString);
var blobClient = account.CreateCloudBlobClient();
var container = blobClient.GetContainerReference(containerName);
var file = uri;
var blob = container.GetBlockBlobReference(file);
//First fetch the size of the blob. We use this to create an empty file with size = blob's size
blob.FetchAttributes();
var blobSize = blob.Properties.Length;
long blockSize = (1 * 1024 * 1024);//1 MB chunk;
blockSize = Math.Min(blobSize, blockSize);
//Create an empty file of blob size
using (FileStream fs = new FileStream(file, FileMode.Create))//Create empty file.
{
fs.SetLength(blobSize);//Set its size
}
var blobRequestOptions = new BlobRequestOptions
{
RetryPolicy = new ExponentialRetry(TimeSpan.FromSeconds(5), 3),
MaximumExecutionTime = TimeSpan.FromMinutes(60),
ServerTimeout = TimeSpan.FromMinutes(60)
};
long startPosition = 0;
long currentPointer = 0;
long bytesRemaining = blobSize;
do
{
var bytesToFetch = Math.Min(blockSize, bytesRemaining);
using (MemoryStream ms = new MemoryStream())
{
//Download range (by default 1 MB)
blob.DownloadRangeToStream(ms, currentPointer, bytesToFetch, null, blobRequestOptions);
ms.Position = 0;
var contents = ms.ToArray();
using (var fs = new FileStream(file, FileMode.Open))//Open that file
{
fs.Position = currentPointer;//Move the cursor to the end of file.
fs.Write(contents, 0, contents.Length);//Write the contents to the end of file.
}
startPosition += blockSize;
currentPointer += contents.Length;//Update pointer
bytesRemaining -= contents.Length;//Update bytes to fetch
Console.WriteLine(fileName + dateTimeStamp + ".csv " + (startPosition / 1024 / 1024) + "/" + (blob.Properties.Length / 1024 / 1024) + " MB downloaded...");
}
}
while (bytesRemaining > 0);
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