/// <summary>
/// Downloads the specified blob to the specified location.
/// </summary>
/// <param name="uri">The blob url from which file a needs should be downloaded. If blob has private read permissions then an appropriate SAS url need to be passed.</param>
/// <param name="localFile">The full path where file will be saved.</param>
/// <param name="fileEncryption">The file encryption if file has been encrypted. Pass null if no encryption has been used.</param>
/// <param name="initializationVector">The initialization vector if encryption has been used.</param>
/// <param name="client">The azure client to access a blob.</param>
/// <param name="cancellationToken">The cancellation token to cancel the download operation.</param>
/// <param name="retryPolicy">The RetryPolicy delegate returns a ShouldRetry delegate, which can be used to implement a custom retry policy.RetryPolicies class can bee used to get default policies</param>
/// <param name="getSharedAccessSignature">A callback function which returns Sas signature for the file to be downloaded</param>
/// <param name="start">Start pos to download</param>
/// <param name="length">Number of bytes to download, -1 to download all.</param>
/// <returns>A task that downloads the specified blob.</returns>
public virtual Task DownloadBlob(
Uri uri,
string localFile,
FileEncryption fileEncryption,
ulong initializationVector,
CloudBlobClient client,
CancellationToken cancellationToken,
IRetryPolicy retryPolicy,
Func<string> getSharedAccessSignature = null,
long start = 0,
long length = -1
)
{
if (client != null && getSharedAccessSignature != null)
{
throw new InvalidOperationException("The arguments client and sharedAccessSignature cannot both be non-null");
}
if (start < 0)
{
throw new ArgumentException(string.Format(CultureInfo.CurrentCulture, "Initial offset {0} to download a file must not be negative", start));
}
// To download the asset file as a whole or byte-range, the localFile should not be empty
if (string.IsNullOrEmpty(localFile))
{
throw new ArgumentException("Parameter localFile must be set with a full path");
}
if (length < -1)
{
throw new ArgumentException("Parameter length must be equals or greater than -1");
}
if (_forceSharedAccessSignatureRetry != TimeSpan.Zero)
{
// The following sleep is for unit test purpose and we will force the shared access signature to expire and hit retry code path
Thread.Sleep(_forceSharedAccessSignatureRetry);
}
BlobDownloader blobDownloader = new BlobDownloader(new MemoryManagerFactory());
blobDownloader.TransferCompleted += (sender, args) =>
{
if (TransferCompleted != null)
{
TransferCompleted(sender, args);
}
else if (args.Error != null)
{
throw args.Error;
}
};
blobDownloader.TransferProgressChanged += (sender, args) =>
{
if (TransferProgressChanged != null)
{
TransferProgressChanged(sender, args);
}
};
return blobDownloader.DownloadBlob(
uri,
localFile,
fileEncryption,
initializationVector,
client,
cancellationToken,
retryPolicy,
getSharedAccessSignature,
start,
length,
parallelTransferThreadCount: ParallelTransferThreadCount,
numberOfConcurrentTransfers: NumberOfConcurrentTransfers);
}
/// <summary>
/// Downloads the specified blob to the specified location.
/// </summary>
/// <param name="uri">The blob url from which file a needs should be downloaded. If blob has private read permissions then an appropriate SAS url need to be passed.</param>
/// <param name="localFile">The full path where file will be saved.</param>
/// <param name="fileEncryption">The file encryption if file has been encrypted. Pass null if no encryption has been used.</param>
/// <param name="initializationVector">The initialization vector if encryption has been used.</param>
/// <param name="client">The azure client to access a blob.</param>
/// <param name="cancellationToken">The cancellation token to cancel the download operation.</param>
/// <param name="retryPolicy">The RetryPolicy delegate returns a ShouldRetry delegate, which can be used to implement a custom retry policy.RetryPolicies class can bee used to get default policies</param>
/// <param name="getSharedAccessSignature">A callback function which returns Sas signature for the file to be downloaded</param>
/// <param name="start">Start pos to download</param>
/// <param name="length">Number of bytes to download, -1 to download all.</param>
/// <returns>A task that downloads the specified blob.</returns>
public virtual Task DownloadBlob(
Uri uri,
string localFile,
FileEncryption fileEncryption,
ulong initializationVector,
CloudBlobClient client,
CancellationToken cancellationToken,
IRetryPolicy retryPolicy,
Func<string> getSharedAccessSignature = null,
long start = 0,
long length = -1
)
{
if (client != null && getSharedAccessSignature != null)
{
throw new InvalidOperationException("The arguments client and sharedAccessSignature cannot both be non-null");
}
if (start < 0)
{
throw new ArgumentException(string.Format(CultureInfo.CurrentCulture, "Initial offset {0} to download a file must not be negative", start));
}
// To download the asset file as a whole or byte-range, the localFile should not be empty
if (string.IsNullOrEmpty(localFile))
{
throw new ArgumentException("Parameter localFile must be set with a full path");
}
if (length < -1)
{
throw new ArgumentException("Parameter length must be equals or greater than -1");
}
if (_forceSharedAccessSignatureRetry != TimeSpan.Zero)
{
// The following sleep is for unit test purpose and we will force the shared access signature to expire and hit retry code path
Thread.Sleep(_forceSharedAccessSignatureRetry);
}
BlobDownloader blobDownloader = new BlobDownloader(new MemoryManagerFactory());
blobDownloader.TransferCompleted += (sender, args) =>
{
if (TransferCompleted != null)
{
TransferCompleted(sender, args);
}
else if (args.Error != null)
{
throw args.Error;
}
};
blobDownloader.TransferProgressChanged += (sender, args) =>
{
if (TransferProgressChanged != null)
{
TransferProgressChanged(sender, args);
}
};
return blobDownloader.DownloadBlob(
uri,
localFile,
fileEncryption,
initializationVector,
client,
cancellationToken,
retryPolicy,
getSharedAccessSignature,
start,
length,
parallelTransferThreadCount: ParallelTransferThreadCount,
numberOfConcurrentTransfers: NumberOfConcurrentTransfers);
}