The status of a each individual document in the batch
The source of the document, same as the [input_gcs_source]
field in the request when the batch process started. The
batch process is started by take snapshot of that document,
since a user can move or change that document during the
The status of the processing of the document.
The output_gcs_destination (in the request as
'output_gcs_destination') of the processed document if it
was successful, otherwise empty.