FAQ

Note that all code samples below should be run before the init action hook and not earlier than the plugins_loaded (or muplugins_loaded if you use the plugin as a must-use plugin) hook.

Installation Instructions

As a regular plugin

1. Upload the entire attachment-taxonomies folder to the /wp-content/plugins/ directory or download it through the WordPress backend.
2. Activate the plugin through the ‘Plugins’ menu in WordPress.

As a must-use plugin

If you don’t know what a must-use plugin is, you might wanna read its introduction in the WordPress Codex – don’t worry, that’s nothing purely for developers.

1. Upload the entire attachment-taxonomies folder to the /wp-content/mu-plugins/ directory (create the directory if it doesn’t exist).
2. Move the file /wp-content/mu-plugins/attachment-taxonomies/attachment-taxonomies.php out of its directory to /wp-content/mu-plugins/attachment-taxonomies.php.

Note that, while must-use plugins have the advantage that they cannot be disabled from the admin area, they cannot be updated through WordPress, so you’re recommended to keep them up to date manually.

Administration

Once the plugin is activated, you will see two new submenu items under Media (Categories and Tags). The plugin follows the WordPress Core philosophy “Decisions, not Options” – therefore there is no additional settings screen. However, the plugin is easily extendable and adjustable by developers (see FAQ). So if the base configuration does not suit your needs, it shouldn’t be too hard to change that.

How can I add more attachment taxonomies?

You can simply use the WordPress Core function register_taxonomy() and specify 'attachment' as the second parameter. As an alternative, you can create your own class for the taxonomy, extending the abstract Attachment_Taxonomy class provided by the plugin. Then you can add it using the method add_taxonomy( $taxonomy ) of the class Attachment_Taxonomies.

Example Code (adds an attachment taxonomy called “Location”):

<?php

final class Attachment_Location extends Attachment_Taxonomy {
    protected $slug = 'attachment_location';
    protected $labels = array(
        'name'              => __( 'Locations', 'textdomain' ),
        'singular_name'     => __( 'Location', 'textdomain' ),
        /* more labels here... */
    );
    protected $args = array(
        'hierarchical'      => true,
        'query_var'         => 'location',
        /* more arguments here... */
    );
}

Attachment_Taxonomies::instance()->add_taxonomy( new Attachment_Location() );

How can I remove the default attachment taxonomies?

To remove one of the default attachment taxonomies you should call the method remove_taxonomy( $taxonomy_slug ) of the class Attachment_Taxonomies.

Example Code (removes the attachment taxonomy “Category”):

<?php

Attachment_Taxonomies::instance()->remove_taxonomy( 'attachment_category' );

How can I use the regular post categories and post tags for attachments instead of the additional taxonomies ?

To accomplish that, first you need to remove the two taxonomies that the plugin adds (attachment_category and attachment_tag). See above for instructions on how to do that.

Then you can simply use the WordPress Core function register_taxonomy_for_object_type() and specify 'attachment' as the second parameter. As an alternative, you can create your own instance of the Attachment_Existing_Taxonomy class provided by the plugin. Then you can add it using the method add_taxonomy( $taxonomy, $existing ) of the class Attachment_Taxonomies, with the second parameter set to true.

Example Code (makes the regular category and tag taxonomies available for attachments):

<?php

Attachment_Taxonomies::instance()->add_taxonomy( new Attachment_Existing_Taxonomy( 'category' ), true );
Attachment_Taxonomies::instance()->add_taxonomy( new Attachment_Existing_Taxonomy( 'post_tag' ), true );

How do I use the enhanced version of the `[gallery]` shortcode?

The [gallery] shortcode can now be passed taxonomy attributes. They have to have the attachment taxonomy slug as the attribute name and a comma-separated list of term slugs or term IDs as value. You may also specify a new “limit” attribute to limit the amount of images shown. This is especially recommended if the attachment taxonomy term you are querying for contains a lot of images.

Example Code (shows images with attachment categories 1 or 2 or attachment tag 5 with a limit of 20 images shown):

[gallery attachment_category="1,2" attachment_tag="5" limit="20"]

Note that there is currently no UI in the backend for this, and the preview in the editor will not work properly. It will show up correctly in the frontend though.

Which filters are available in the plugin?

The plugin provides some filters to adjust taxonomy arguments and labels.

• attachment_taxonomy_args where first argument is the array of taxonomy arguments and the second argument is the taxonomy slug that these arguments apply to
• attachment_taxonomy_{$taxonomy_slug}_args where the only argument is the array of taxonomy arguments for the taxonomy defined by $taxonomy_slug
• attachment_taxonomy_labels where first argument is the array of taxonomy labels and the second argument is the taxonomy slug that these labels apply to
• attachment_taxonomy_{$taxonomy_slug}_labels where the only argument is the array of taxonomy labels for the taxonomy defined by $taxonomy_slug

Where should I submit my support request?

I preferably take support requests as issues on Github, so I would appreciate if you created an issue for your request there. However, if you don’t have an account there and do not want to sign up, you can of course use the wordpress.org support forums as well.

How can I contribute to the plugin?

If you’re a developer and you have some ideas to improve the plugin or to solve a bug, feel free to raise an issue or submit a pull request in the Github repository for the plugin.

You can also contribute to the plugin by translating it. Simply visit translate.wordpress.org to get started.