Skip to content

wordpress

Directory actions

More options

Directory actions

More options

Latest commit

 

History

History

wordpress

Folders and files

NameName
Last commit message
Last commit date

parent directory

..
README.md
README.md
 
 
thumbapi-on-publish.php
thumbapi-on-publish.php
 
 

README.md

WordPress

There are two ways to use ThumbAPI inside WordPress.

👉 Most users: the official plugin

The recommended way is the official ThumbAPI — Auto Featured Images plugin. It adds a one-click "Generate" button to the post editor (block + classic), an integrated Media Library picker for "With image" / "With logo" styles, a settings page, a content-category selector, and full WordPress.org Plugin Directory compliance.

Install: WordPress admin → Plugins → Add New Plugin → Upload Plugin → choose the zip → Install Now → Activate. Then Settings → ThumbAPI → paste your API key.

🧑‍💻 Developers: single-file auto-on-publish example

This folder also contains a minimal single-file example showing how to call the ThumbAPI endpoint from PHP and set the result as a featured image. Unlike the official plugin, this example fires automatically on transition_post_status — every newly published post that doesn't already have a featured image gets one without any UI interaction.

Useful when:

  • You're building a custom integration and want to see the raw wp_remote_post + Media Library sideload flow in one file (~100 lines).
  • You want fully automated cover generation on publish, with no editor button.
  • You want to fork and customize the behaviour (e.g. only certain post types, custom format/style logic, multi-site rollouts).

What this example does

When a post transitions from any status to publish, the plugin:

  1. Sends the post title to https://api.thumbapi.dev/v1/generate.
  2. Decodes the returned base64 WebP.
  3. Uploads it to the WordPress Media Library.
  4. Sets it as the post's featured image (post thumbnail).

If the post already has a featured image, the plugin does nothing — it only fills in missing ones.

Install (example)

  1. Copy thumbapi-on-publish.php into your WordPress installation under: 
    wp-content/plugins/thumbapi-on-publish/thumbapi-on-publish.php
  2. In WordPress admin → Plugins, activate "ThumbAPI — Auto Featured Image on Publish".
  3. Go to Settings → ThumbAPI on Publish and paste your API key. Get one at app.thumbapi.dev.

Publish a post (or update an existing post to "Published" status) and the featured image gets generated automatically.

Configuration

The settings page lets you pick:

  • API key — required.
  • Format — blogpost (default, 1200×630) is best for WordPress featured images and OG previews. You can also use youtube, instagram, x, or linkedin.
  • Image style — faceless (default), with-image, or with-logo.

For brand-consistent output (your logo on every image), set the style to with-logo and upload your logo once in the ThumbAPI dashboard under Assets — the plugin uses it automatically. See the custom assets guide.

Use cases for the example

  • Blogs publishing daily — every post gets a unique cover without designer time.
  • Headless WordPress — generate the OG image automatically so social previews don't look broken.
  • Multi-author sites — consistent visual style across all authors' posts.

How it works internally

The plugin hooks into transition_post_status so it only fires once per publish, not on every save. It uses the WordPress HTTP API (wp_remote_post), the Media API (wp_insert_attachment, wp_generate_attachment_metadata), and set_post_thumbnail. All standard WP — no external PHP dependencies.

See also