I want to generate SAS URL dynamically via C# code for Azure Blob Container. Using this SAS URL we must be able to upload the files - azure

Question

I want to generate SAS URL dynamically via C# code for Azure Blob Container. Using this SAS URL we must be able to upload the files to the Azure Blob Container. I have tried multiple ways to generate the SAS URL by following the Microsoft docs. But I am always getting AuthorizationResourceTypeMismatch Error or AuthorizationPermissionMismatch.
Error: AuthorizationPermissionMismatch This request is not authorized to perform this operation using this permission.
private static Uri GetServiceSasUriForContainer(BlobContainerClient containerClient,
string storedPolicyName = null)
{
// Check whether this BlobContainerClient object has been authorized with Shared Key.
if (containerClient.CanGenerateSasUri)
{
// Create a SAS token that's valid for one hour.
BlobSasBuilder sasBuilder = new BlobSasBuilder()
{
BlobContainerName = containerClient.Name,
Resource = "c"
};
if (storedPolicyName == null)
{
sasBuilder.ExpiresOn = DateTimeOffset.UtcNow.AddHours(1);
sasBuilder.SetPermissions(BlobContainerSasPermissions.Read);
}
else
{
sasBuilder.Identifier = storedPolicyName;
}
Uri sasUri = containerClient.GenerateSasUri(sasBuilder);
Console.WriteLine("SAS URI for blob container is: {0}", sasUri);
Console.WriteLine();
return sasUri;
}
else
{
Console.WriteLine(#"BlobContainerClient must be authorized with Shared Key
credentials to create a service SAS.");
return null;
}
}
Error: AuthenticationFailed Server failed to authenticate the request. Make sure the value of Authorization header is formed correctly including the signature.
I need this sas url because I use this url in my javascript to upload files into the Azure Blob Container.
Can someone help me out achieving this goal?

Answer 1

The reason you're getting this error is because you are creating the SAS token with Read permission (BlobContainerSasPermissions.Read).
In order to upload a blob in a container using SAS URL, the SAS token needs either Write (BlobContainerSasPermissions.Write) or Create (BlobContainerSasPermissions.Create) permission. Please create a SAS token with one of these permissions and you should not get this error.
To learn more about the permissions, please see this link: https://learn.microsoft.com/en-us/rest/api/storageservices/create-service-sas#permissions-for-a-directory-container-or-blob.