/// <summary>
/// Get blob shared access signature
/// </summary>
/// <param name="blob">CloudBlob object</param>
/// <param name="accessPolicy">SharedAccessBlobPolicy object</param>
/// <param name="policyIdentifier">The existing policy identifier.</param>
/// <returns></returns>
private string GetBlobSharedAccessSignature(CloudBlob blob, SharedAccessBlobPolicy accessPolicy, string policyIdentifier, SharedAccessProtocol?protocol, IPAddressOrRange iPAddressOrRange, bool generateUserDelegationSas)
{
CloudBlobContainer container = blob.Container;
if (generateUserDelegationSas)
{
Azure.Storage.UserDelegationKey userDelegationKey = Channel.GetUserDelegationKey(accessPolicy.SharedAccessStartTime, accessPolicy.SharedAccessExpiryTime, null, null, OperationContext);
return(blob.GetUserDelegationSharedAccessSignature(userDelegationKey, accessPolicy, null, protocol, iPAddressOrRange));
}
else
{
return(blob.GetSharedAccessSignature(accessPolicy, null, policyIdentifier, protocol, iPAddressOrRange));
}
}
private static string GetBlobSasToken(CloudBlob blob)
{
if (null == blob.ServiceClient.Credentials ||
(blob.ServiceClient.Credentials.IsAnonymous && !blob.ServiceClient.Credentials.IsToken))
{
return(string.Empty);
}
else if (blob.ServiceClient.Credentials.IsSAS)
{
return(blob.ServiceClient.Credentials.SASToken);
}
// SAS life time is at least 10 minutes.
TimeSpan sasLifeTime = TimeSpan.FromMinutes(CopySASLifeTimeInMinutes);
if (blob.ServiceClient.Credentials.IsToken)
{
sasLifeTime = TimeSpan.FromMinutes(CopySASLifeTimeInMinutesOauth);
}
SharedAccessBlobPolicy policy = new SharedAccessBlobPolicy()
{
SharedAccessExpiryTime = DateTime.Now.Add(sasLifeTime),
Permissions = SharedAccessBlobPermissions.Read,
};
CloudBlob rootBlob = null;
if (!blob.IsSnapshot)
{
rootBlob = blob;
}
else
{
rootBlob = Util.GetBlobReference(blob.Uri, blob.ServiceClient.Credentials, blob.BlobType);
}
if (!blob.ServiceClient.Credentials.IsToken) // not oauth, generated normal sas
{
return(rootBlob.GetSharedAccessSignature(policy));
}
else // oauth, generate identity sas
{
DateTimeOffset userDelegationKeyStartTime = DateTime.Now;
DateTimeOffset userDelegationKeyEndTime = userDelegationKeyStartTime.AddMinutes(CopySASLifeTimeInMinutes);
Azure.Storage.UserDelegationKey userDelegationKey = rootBlob.ServiceClient.GetUserDelegationKey(userDelegationKeyStartTime, userDelegationKeyEndTime);
return(rootBlob.GetUserDelegationSharedAccessSignature(userDelegationKey, policy));
}
}
