Every page's image is at:
https://your-site/og-image/<kind>/<id>
| Kind | id | Example |
|---|---|---|
site |
0 |
/og-image/site/0 (the home page) |
item |
item ID | /og-image/item/42 |
collection |
collection ID | /og-image/collection/3 |
file |
file ID | /og-image/file/118 |
exhibit |
exhibit ID | /og-image/exhibit/2 |
exhibit_page |
exhibit page ID | /og-image/exhibit_page/7 |
simple_page |
simple page ID | /og-image/simple_page/1 |
blog_post |
blog post ID | /og-image/blog_post/4 |
search |
the words searched for | /og-image/search/steel%20sculpture |
The answer is a PNG (Content-Type: image/png), cached by browsers and networks for a day. Pages link to it with a version, ?v=…, which changes when the record or the template changes.
It answers 404 when the kind is turned off under Settings, when sharing images are off, or when the record does not exist or is not public (for a blog post: not yet published). The address is public on purpose: networks fetch it without signing in.
The tags pages get
<meta property="og:image" content="https://your-site/og-image/item/42?v=3fa24ab7">
<meta property="og:image:width" content="1200">
<meta property="og:image:height" content="630">
<meta property="og:image:type" content="image/png">
<meta name="twitter:card" content="summary_large_image">
<meta name="twitter:image" content="https://your-site/og-image/item/42?v=3fa24ab7">
With Vitrine, Confetti, Plinth and Overprint, the theme writes these with its other sharing tags (title, description, address), through the Theme Engine's theme_engine_share_image filter. With other themes, OG Images writes them in the page head.