Every resource type has one module-wide default template. On a multi-site installation you can point any site at a different template for any resource type. There are two places to do this; both write to the same override table.
From the site admin page
- Go to Admin > Sites and open the site.
- Scroll to the OG Image Templates section at the bottom of the site's page. The same section is shown on the site's Edit page.
- For each resource type, choose a template from the drop-down. The list only shows templates whose resource type matches the row. The module default is marked "(default)". Leave Use default to inherit the module-wide default.
- Click Save OG Template Overrides. The form is submitted in the background and a confirmation "OG template overrides saved." appears below the button.
Saving clears the cached images for every resource type listed, so the next share of a page on that site renders with the new template.
From the template
- Go to Admin > OG Images and edit a template.
- In the Site Assignments section, tick each site that should use this template for the template's resource type.
- Click Save.
Ticking a site sets its override for this template's resource type, replacing any other template it was assigned. Unticking a site removes its override only if it currently points to this template; a site assigned to a different template is left alone. The Sites column on the template list shows which sites use each template, or "All sites (default)" when no site is assigned.
How the template is chosen
When an image is requested for a resource on a site, the module looks for, in order:
- a site override for that resource type;
- the template marked as default for that resource type;
- the template marked as default for the special Default (all types) resource type;
- a built-in fallback design compiled into the module.
The site_id query parameter on the image URL identifies the site. If it is missing, step 1 is skipped.