Is it possible to add a link to download a file that can only be downloaded by sharing it on Facebook?

Question

Is this scenario possible?

Customer goes to my website, wants to download a PDF technical document that interests them, they click the Download button and a Facebook

Answer 1

Thank you, works perfect! I Didn't know how to get the download link from a JSON file, so I did it slightly different, maybe not that safe.

Add this to the section where the response is checked

$.post('optimus.php', { 'fieldname' : 'download', 'value' : 'yes'});

Made a new page where the session is set (optimus.php)

Download.php contains the following code

So, when the user shared something, the $_SESSION['download'] is set to yes. Download.php checks if it's yes and when it is the download is automatically started. Also, the session is destroyed so they can only download once.