Montecchiani Book Catalog

Montecchiani Book Catalog adds a dedicated Book content type to WordPress and displays your books anywhere on your site with the [mbcat_books] shortcode: a responsive 1–5 column grid of covers with an overlay that reveals the book details on hover, on focus or on tap. Every book stores its own details (author, publisher, publication year, number of pages, language, ISBN and an optional shop link), can be organised with the Genres taxonomy, and is automatically described with Schema.org Book structured data (JSON-LD) so search engines can show rich results. ISBN autofill Type an ISBN in the book editor and click Autofill from ISBN. The plugin queries the Google Books and Open Library catalogs and fills in the empty fields only — title, author, publisher, year, pages, language and description — never overwriting anything you already wrote. If a cover is found you can import it into the Media Library and set it as the featured image with one click. Main features

• Custom Book post type with cover, excerpt and full editor support (block editor ready)
• Genres taxonomy to organise and filter the catalog
• Book fields: author, publisher, publication year, pages, language, ISBN, shop link
• ISBN autofill from Google Books and Open Library, with the results merged and cached
• Cover import: one click to store the cover in the Media Library as the featured image
• [mbcat_books] shortcode with columns, hitem, orderby, order and genre attributes
• Responsive grid (1–5 columns), hover overlay, keyboard accessible, touch friendly
• "Show All Books" button that loads the rest of the catalog over AJAX
• Schema.org Book JSON-LD structured data for SEO
• Admin list columns for cover, author, year and ISBN, sortable by author and year
• Settings page: default author, author label, columns, ISBN data source, uninstall cleanup
• Fully translatable — French, Spanish, Italian and Japanese translations are prepared for translate.wordpress.org, where any other language can be contributed too
• Assets are only loaded on the pages that actually use the shortcode

External services This plugin can query two third-party book databases in order to autofill book details from an ISBN. Every request is made from your server, only inside the WordPress admin, and only when a logged-in editor clicks the "Autofill from ISBN" button or the "Use as cover" button. Nothing is ever sent from the public side of your site, no request is made automatically or in the background, and no personal data about you or your visitors is transmitted. Google Books API — endpoint: https://www.googleapis.com/books/v1/volumes What is sent, and when: the ISBN you typed, each time you click "Autofill from ISBN" (unless you disabled this source in the settings) and, if the cached result of that lookup has expired in the meantime, again when you click "Use as cover". If you entered an optional Google Books API key in the plugin settings, that key is sent with the request too. Every request also carries a User-Agent header identifying the plugin and its version (Montecchiani-Book-Catalog/1.3.1); your site URL is not sent. When the answer includes a cover, your server also downloads its small thumbnail (a few kilobytes) from the address returned by the API, on books.google.com or its file host books.googleusercontent.com, and embeds it in the editor as a preview: the editor page itself never loads anything from Google. If you then click "Use as cover", the cover image file is downloaded from the same address by your server and stored permanently in your site's Media Library. Terms of Service: https://developers.google.com/books/terms and https://policies.google.com/terms Privacy Policy: https://policies.google.com/privacy Open Library API (Internet Archive) — endpoint: https://openlibrary.org/api/books What is sent, and when: the ISBN you typed, each time you click "Autofill from ISBN" (unless you disabled this source in the settings) and, if the cached result of that lookup has expired in the meantime, again when you click "Use as cover". Every request also carries a User-Agent header identifying the plugin and its version (Montecchiani-Book-Catalog/1.3.1); your site URL is not sent. When the answer includes a cover, your server also downloads its small thumbnail (a few kilobytes) from the address returned by the API, on covers.openlibrary.org (which may redirect to archive.org, the Internet Archive's file server), and embeds it in the editor as a preview: the editor page itself never loads anything from Open Library. If you then click "Use as cover", the cover image file is downloaded from the same address by your server and stored permanently in your site's Media Library. Terms of Use: https://archive.org/about/terms.php Privacy Policy: https://archive.org/about/terms.php Please note that cover images downloaded from these services are third-party content: it is your responsibility to check that you are allowed to publish them on your site. You can choose which of the two services is used — or use only one of them — in Book Catalog → Settings → ISBN Autofill. Lookup results and cover previews are cached on your own server for 12 hours so that repeated lookups do not generate new outgoing requests.

1.3.1

• Fixed: the cover preview in the book editor was loaded by the browser straight from Google Books or Open Library. The preview is now downloaded by the server together with the lookup and embedded in the response, so the editor never loads a file from a third-party host.
• Changed: the cover import no longer accepts a URL from the browser. The server resolves the cover from its own cached lookup of the ISBN, so the cover-host allowlist and the mbcat_allowed_cover_hosts filter are gone.
• Changed: cover downloads are limited to 10 MB and previews to 128 KB.
• Privacy: the cover download no longer sends your site URL, which the default WordPress User-Agent carried.
• Fixed: the Plugin URI pointed at a repository that does not exist.

1.3.0

• Changed: the plugin is now named Montecchiani Book Catalog. Post type, taxonomy, shortcode, options, transients, AJAX actions and every PHP symbol now carry the mbcat prefix to rule out collisions with other plugins.
• Changed: the shortcode is [mbcat_books]. The former unprefixed [books] name (and its [wpbc_books] alias) registered a generic name that other plugins may legitimately want.
• Changed: translation files are no longer bundled; translations are delivered automatically through translate.wordpress.org.

1.2.0

• Fixed: importing a cover from Google Books could never work. Those URLs carry no file extension, which media_sideload_image() rejects outright; covers are now downloaded first and typed from their actual content.
• Fixed: ordering by year or author sorted the books that had no value at all by an unrelated meta value, so their position was effectively random. Ordering now uses a single keyed LEFT JOIN; books without a value always come last.
• Fixed: the "Default Author" setting was written into a book's own meta the first time the book was saved, so changing the setting later no longer affected existing books. It is now shown as a placeholder and resolved when the book is displayed.
• Fixed: the admin stylesheet restyled core WordPress tables and headings on every Book screen. All admin styles are now scoped to the plugin's own markup.
• Fixed: uninstalling with "Delete Data on Uninstall" enabled left every genre behind and skipped books in the Trash, and it only cleaned the current site on multisite.
• Fixed: network-activating on multisite set up only one site, leaving the other sites without rewrite rules or settings. New sites are now set up automatically too.
• Fixed: the "Show All Books" button stopped working on sites with full-page caching once the cached nonce expired. The endpoint is read-only and public, and no longer uses one.
• Fixed: the book details overlay was hidden from screen readers, and the non-linked cards were focusable without any role. Publication year and page count could not be cleared.
• Fixed: submitting an array value for a book field could fatal on PHP 8.
• Security: importing a cover now also requires the upload_files capability, the host allowlist is matched case-insensitively and applied to the lookup response as well, and cover URLs are passed through esc_url_raw().
• Privacy: the plugin no longer sends your site URL to Google Books / Open Library.
• Privacy: the Google Books API key is no longer rendered back into the settings page.
• Added: [wpbc_books], a prefixed alias of the original [books] shortcode (both were replaced by [mbcat_books] in 1.3.0).
• Added: a 500-book cap per request, adjustable with mbcat_max_books_per_request.
• Added: the mbcat_shortcode_query_args, mbcat_allowed_cover_hosts and mbcat_lookup_data filters.
• Added: readme.txt, a bundled copy of the GPLv2 licence and a .distignore.
• Improved: the JSON-LD block is refreshed when "Show All Books" expands the catalog, and the books admin list now shows the default author like the front end does.
• Added: French, Spanish and Japanese translations, alongside the existing Italian one.
• Removed: the manual load_plugin_textdomain() call, which WordPress has not needed since 4.6.

1.1.0

• Added ISBN autofill from Google Books and Open Library, with cover import.
• Added Schema.org Book structured data (JSON-LD).
• Added admin list columns for cover, author, year and ISBN, sortable by author and year.
• Added the Genres taxonomy filter to the shortcode.
• Added the settings page options for the ISBN data source and uninstall cleanup.

1.0.0

• First release: Book post type, book fields, [mbcat_books] shortcode, responsive grid with hover overlay, "Show All Books" AJAX button, settings page and Italian translation.