How can you get a thumbnail when you share a PDF on Facebook

Question

One of my clients writes cookbooks. Some time ago, he wrote an article about the origins of Boston Cream Pie, which he has on his site as a PDF on a page of links to various articles he has written.

I would like to share that PDF on Facebook, but the PDF doesn't give Facebook any Open Graph tags, so the link is rather ugly

Is there an Open Graph implementation for PDF URLs that would give his readers a good social media link besides creating a new page with text and images that are more Open Graph friendly?

Answer 1

No, there is no such implementation. Open Graph metadata comes from specifically formatted links on a web page, and not from the PDF document itself (or a link to download it). You must create a dedicated page for the PDF to be downloaded from, and put the Open Graph metadata on that page.

Facebook's reference documentation page is here, and as you can see it does not include anything about PDFs: https://developers.facebook.com/docs/reference/opengraph/