If your content has additional data that you'd like to offer as downloads, try using a File field.
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Adding a file field
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Editing a file field
{
"name": "file_field",
"label": "File Field",
"class": "file",
"value": {
"id": 124,
"alt": "",
"title": "Pizza_with_tomatoes",
"caption": "",
"description": "",
"mime_type": "image/jpeg",
"url": "//docs.rooftop.io/sites/2/2016/08/19103231/Pizza_with_tomatoes-1.jpg"
}
}
See more information on this field.