$response:download[DATA]
This field is identical to $response:body, but it sets flag that browser interprets as "Suggest that visitor save file to disk."
Browsers are able to display certain file types right within their windows (for example: .doc, .pdf files).
Still, sometimes we should enable a visitor to download the file by simply clicking a relevant link.
Example: outputting a PDF file A visitor is at page with such HTML:
<a href="/download_documentation.html">Download documentation</a>
download_documentation.html:
$response:download[^file::load[binary;documentation.pdf]]
…visitor clicks the link and browser suggests Open/Download.