Headless Batch Import: Attachment Field with URL Creates Duplicate Empty File

Issue

When using the Headless Batch Engine to import Object Entries with an attachment field using a file URL, following the documentation here, we see that it creates duplicate empty files.

Environment

Liferay DXP Quarterly Releases

Resolution

The current documentation (at the time of writing the article) is misleading using an example of a document in documents and media. http://localhost:8080/documents/d/guest/treepic

Incorrect curl below:

curl -X "POST" "http://localhost:8080/o/c/imageObject?restrictFields=actions" \
     -H "Content-Type: application/json" \
     -u 'test@liferay.com:learn' \
     -d { "picture": { "fileURL": "http://localhost:8080/documents/d/guest/treepic", "name": "tree.png" } }

The fileURL property is meant for adding the attachment from an external resource.
The system fetches that file, upload it to Liferay and link it with the object entry.
It is meant to make the process of document upload easier.
If the document is already in the documents library, the way to go is use either the Id or the ERC to make the link.
We are changing the misleading official documentation on this topic.