Add multiple unknown attachments

I have been trying to create a process to add multiple document level attachments (images), count and filenames unknown at design time.

Any examples?

I am at the point where I have a loop through the list of documents (attachments), setting the current attachment and its filename in a variable, then calling AssemblerService.invokeDDX for each.

The DDX validation tells me "process:///process_data/@currentFilename" is not a valid filename.

I have tried with listOfFilenames[/process_data/currentIndex], even process:///process_data/listOfFilenames[1]. All fail to validate.

I'm not sure the FileAttachments source gets the correct value either.

<DDX xmlns="http://ns.adobe.com/DDX/1.0/">

  <PDF result="pdfOut" format="PDF">

    <PDF source="pdfIn"/>

    <FileAttachments source="process:///process_data/@currentAtt">

      <File filename="process:///process_data/@currentFilename"/>

    </FileAttachments>

  </PDF>

  <?ddx-source-hint name="pdfIn"?>

</DDX>

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