Access Underlying SQLConnection to set AccessToken

[Reheban]

We are using System Managed Identities that require the accessToken to be set. How do I access the underlying SQLConnection to set the AccessToken property?

Thanks

[ckadluba]

Hello @Reheban and sorry for the late answer.

MSSQL sink supports using Azure managed identities and other Entra ID/AAD authentication methods. It has to be configured using the connection string. The supported methods are documented here: https://learn.microsoft.com/en-us/sql/connect/ado-net/sql/azure-active-directory-authentication?view=sql-server-ver16#setting-azure-active-directory-authentication

I'm not quite sure what you mean by set the accessToken because in the case of managed identity you usually only configure the principal ID which assigned to the managed identity in Entra ID/AAD. You do not have to configure anything else. It is password- and secretless and therefore a quite secure and recommended way of authentication in Azure. The access token is requested when the MSSQL sink connects to the database. This is done by the underlying Microsoft.Data.SqlClient library and it happend completely transparend for your code and also for the MSSQL sink. You never see the token and do not have to set or assign it anywhere in your code or configuration. It is all handled by the SqlClient library.

[Reheban]

Hey @ckadluba

Thanks for the response. I probably should have updated the thread here. Its an old EF6/.Net 4.8 project. Until a couple of months ago, I was still forced to use System.Data.SQLClient for EF, which involved manually setting a token because Active Directory Managed Identity wasnt a supported Auth Type. As I hadnt upgraded, it also affected this sink by using the old assembly rather than Microsoft.Data.SqlClient. Since upgrading, everything works fine.

For others who may have the same problem, Microsoft released support for EF6 for Microsoft.Data.SqlClient in June. See: https://www.nuget.org/packages/Microsoft.EntityFramework.SqlServer for more info.

Thanks for following up.