I have set up a log export for the BigQuery data access logs as per this link.

In my use case, clients don't have permission to access the BigQuery directly. They call REST API which fetches the data from BigQuery and serves it to clients. I need to log some custom information, like user ID which requested the data etc., along with the BigQuery data access logs. I tried using the userAgent field by setting the application name with the user ID but it is not showing up in the data access logs.

Is there a way to log custom information in the data access logs?