| 1 |
<?php |
| 2 |
/* |
| 3 |
Plugin Name: Alt Text Tools |
| 4 |
Description: Exports a CSV file of all images that are actually used in your content, along with their corresponding alt tags. |
| 5 |
Version: 0.4.0 |
| 6 |
Author: NerdPress |
| 7 |
Author URI: https://www.nerdpress.net |
| 8 |
License: GPLv2 |
| 9 |
*/ |
| 10 |
|
| 11 |
if ( ! defined( 'ABSPATH' ) ) |
| 12 |
die( 'YOU SHALL NOT PASS' ); |
| 13 |
|
| 14 |
if ( ! defined( 'NP_ATT_VERSION' ) ) |
| 15 |
define( 'NP_ATT_VERSION', '0.4.0' ); |
| 16 |
|
| 17 |
class NerdpressAltTextTools { |
| 18 |
/** |
| 19 |
* Dedicated custom capability that also grants access to Alt Text Tools. |
| 20 |
* |
| 21 |
* This is intentionally only *honored*, never registered or assigned to |
| 22 |
* any role by the plugin -- so there's no database bloat and no |
| 23 |
* activation/deactivation lifecycle to manage. It grants access only if a |
| 24 |
* site administrator deliberately creates and assigns it (for example with |
| 25 |
* a plugin like User Role Editor), which gives a no-code way to grant |
| 26 |
* access to an arbitrary role or user. |
| 27 |
* |
| 28 |
* @since 0.4.0 |
| 29 |
*/ |
| 30 |
const CUSTOM_CAP = 'manage_alt_text_tools'; |
| 31 |
|
| 32 |
/** |
| 33 |
* @var string. Plugins PRO Api Key |
| 34 |
* |
| 35 |
* This is reserved for the tiered features |
| 36 |
* |
| 37 |
* @since 0.0.1 |
| 38 |
*/ |
| 39 |
private $apikey; |
| 40 |
|
| 41 |
/** |
| 42 |
* Class' initializer |
| 43 |
* |
| 44 |
* @since 0.0.1 |
| 45 |
*/ |
| 46 |
public static function init() { |
| 47 |
$class = __CLASS__; |
| 48 |
new $class; |
| 49 |
} |
| 50 |
|
| 51 |
/** |
| 52 |
* The filterable base capability required to access Alt Text Tools. |
| 53 |
* |
| 54 |
* Defaults to 'manage_options' (Administrators only), matching the |
| 55 |
* plugin's long-standing behavior -- updating the plugin does not expose |
| 56 |
* the tool to any role that couldn't already use it. |
| 57 |
* |
| 58 |
* Filter this to require a different capability instead (a full override). |
| 59 |
* For example, to open access to Editors: |
| 60 |
* |
| 61 |
* add_filter( 'nerdpress_alt_text_tools_cap', function() { |
| 62 |
* return 'edit_others_posts'; |
| 63 |
* } ); |
| 64 |
* |
| 65 |
* ...or to open access down to Authors and up ('publish_posts' excludes |
| 66 |
* Contributors; use 'edit_posts' if you want Contributors included too): |
| 67 |
* |
| 68 |
* add_filter( 'nerdpress_alt_text_tools_cap', function() { |
| 69 |
* return 'publish_posts'; |
| 70 |
* } ); |
| 71 |
* |
| 72 |
* If you'd rather grant access without writing code, assign the dedicated |
| 73 |
* NerdpressAltTextTools::CUSTOM_CAP ('manage_alt_text_tools') capability to |
| 74 |
* a role or user with a plugin like User Role Editor -- see |
| 75 |
* currentUserCanAccess(). |
| 76 |
* |
| 77 |
* @since 0.4.0 |
| 78 |
* |
| 79 |
* @return string The base capability required to access the tool. |
| 80 |
*/ |
| 81 |
public static function getCapability() { |
| 82 |
return apply_filters( 'nerdpress_alt_text_tools_cap', 'manage_options' ); |
| 83 |
} |
| 84 |
|
| 85 |
/** |
| 86 |
* Whether the current user may access Alt Text Tools. |
| 87 |
* |
| 88 |
* Access is granted if the user has EITHER the filterable base capability |
| 89 |
* (see getCapability()) OR the dedicated custom capability (see |
| 90 |
* CUSTOM_CAP). The custom capability is what makes no-code, per-role access |
| 91 |
* possible via a role editor. |
| 92 |
* |
| 93 |
* @since 0.4.0 |
| 94 |
* |
| 95 |
* @return bool |
| 96 |
*/ |
| 97 |
public static function currentUserCanAccess() { |
| 98 |
return current_user_can( self::getCapability() ) || current_user_can( self::CUSTOM_CAP ); |
| 99 |
} |
| 100 |
|
| 101 |
/** |
| 102 |
* A single capability string the current user holds, for use with |
| 103 |
* add_management_page() (which accepts only one capability). |
| 104 |
* |
| 105 |
* Should only be called for a user who already passes currentUserCanAccess(). |
| 106 |
* |
| 107 |
* @since 0.4.0 |
| 108 |
* |
| 109 |
* @return string |
| 110 |
*/ |
| 111 |
private static function menuCapability() { |
| 112 |
return current_user_can( self::getCapability() ) ? self::getCapability() : self::CUSTOM_CAP; |
| 113 |
} |
| 114 |
|
| 115 |
/** |
| 116 |
* Constructor |
| 117 |
* |
| 118 |
* @since 0.0.1 |
| 119 |
*/ |
| 120 |
public function __construct() { |
| 121 |
if ( ! self::currentUserCanAccess() ) |
| 122 |
return; |
| 123 |
|
| 124 |
add_action( 'admin_menu', array( $this, 'settingsPage' ) ); |
| 125 |
add_action( 'wp_ajax_getCsv', array( $this, 'getCsv' ) ); |
| 126 |
|
| 127 |
} |
| 128 |
|
| 129 |
/** |
| 130 |
* Inject JS script(s) into the settings page |
| 131 |
* |
| 132 |
* @since 0.0.1 |
| 133 |
*/ |
| 134 |
public function injectScripts() { |
| 135 |
wp_register_script( 'np_alt_tools_js', plugins_url( 'js/np_alt_tools.js', __FILE__ ), array( 'jquery' ), NP_ATT_VERSION ); |
| 136 |
wp_localize_script( 'np_alt_tools_js', 'np_alt_tools', array( |
| 137 |
'endpoint' => admin_url( 'admin-ajax.php' ), |
| 138 |
'nonce' => wp_create_nonce( 'np_alt_tools_secure_me' ) |
| 139 |
) ); |
| 140 |
wp_enqueue_script( 'np_alt_tools_js' ); |
| 141 |
} |
| 142 |
|
| 143 |
/** |
| 144 |
* Plugin settings page (where most of the action happens ;) |
| 145 |
* Use injectScripts to insert admin scripts only on the settings page |
| 146 |
* |
| 147 |
* @since 0.0.1 |
| 148 |
*/ |
| 149 |
public function settingsPage() { |
| 150 |
$hookSuffix = add_management_page( |
| 151 |
'Alt Text Tools', |
| 152 |
'Alt Text Tools', |
| 153 |
self::menuCapability(), |
| 154 |
'nerdpress-alt-text-tools', |
| 155 |
array( $this, 'settingsHtml' ) |
| 156 |
); |
| 157 |
add_action( 'admin_print_scripts-' . $hookSuffix, array( $this, 'injectScripts' ) ); |
| 158 |
} |
| 159 |
|
| 160 |
/** |
| 161 |
* Markup for the settings page |
| 162 |
* |
| 163 |
* @since 0.0.1 |
| 164 |
*/ |
| 165 |
public function settingsHtml() { |
| 166 |
?> |
| 167 |
<div class="wrap"> |
| 168 |
<h1>NerdPress Alt Text Tools</h1> |
| 169 |
<div class="button" id="npatt-csv-action" style="margin-top:30px">Download Alt Tag CSV</div> |
| 170 |
</div> |
| 171 |
<?php |
| 172 |
} |
| 173 |
|
| 174 |
private static function escapeCsv( $fields_array ) { |
| 175 |
$result = []; |
| 176 |
foreach( $fields_array as $field => $value ) { |
| 177 |
// Escape double quotes by doubling them. |
| 178 |
$value = str_replace( '"', '""', $value ); |
| 179 |
|
| 180 |
// Enclose in double quotes if it contains special characters |
| 181 |
if ( preg_match( '/[,"\r\n]/', $value ) ) { |
| 182 |
$value = '"' . $value . '"'; |
| 183 |
} |
| 184 |
|
| 185 |
$result[] = $value; |
| 186 |
} |
| 187 |
return $result; |
| 188 |
} |
| 189 |
|
| 190 |
private static function getImageNameFromUrl( $img_url ) { |
| 191 |
$path_parts = explode( '/', $img_url ); |
| 192 |
$len = count( $path_parts ); |
| 193 |
if ( empty( $path_parts[ $len - 1 ] ) ) |
| 194 |
$image_name = $path_parts[ $len - 2 ]; |
| 195 |
else |
| 196 |
$image_name = $path_parts[ $len - 1 ]; |
| 197 |
|
| 198 |
// Strip the size of the image |
| 199 |
return preg_replace( '/-[0-9]+x[0-9]+/', '', $image_name ); |
| 200 |
} |
| 201 |
|
| 202 |
/** |
| 203 |
* The CSV columns, in output order: internal key => human header. |
| 204 |
* |
| 205 |
* The internal keys are also the keys of each associative row returned by |
| 206 |
* buildRows(), which keeps the data layer self-describing for structured |
| 207 |
* consumers (e.g. the Abilities API). |
| 208 |
* |
| 209 |
* @return array |
| 210 |
*/ |
| 211 |
private static function csvColumns() { |
| 212 |
return array( |
| 213 |
'post_id' => 'post id', |
| 214 |
'post_type' => 'post_type', |
| 215 |
'page_title' => 'page title', |
| 216 |
'page_url' => 'page url', |
| 217 |
'image_url' => 'image url', |
| 218 |
'alt' => 'image alt tag', |
| 219 |
'edit_link' => 'edit link', |
| 220 |
'media_link' => 'media library link', |
| 221 |
); |
| 222 |
} |
| 223 |
|
| 224 |
/** |
| 225 |
* Scan all public content and return every discovered image as an |
| 226 |
* associative row (keyed by self::csvColumns() keys). |
| 227 |
* |
| 228 |
* This is the pure data layer -- it performs no request handling or |
| 229 |
* output, so it can back both the AJAX download (getCsv()) and the |
| 230 |
* Abilities API ability. The 'alt' value is the image's alt text, or the |
| 231 |
* sentinel 'MISSING' (no alt attribute) / 'EMPTY' (alt=""). |
| 232 |
* |
| 233 |
* @return array[] List of associative rows. |
| 234 |
*/ |
| 235 |
public static function buildRows() { |
| 236 |
/*============================= |
| 237 |
* Get all the posts/pages etc. |
| 238 |
*=============================*/ |
| 239 |
$opts = array( |
| 240 |
'public' => TRUE, |
| 241 |
'_builtin' => FALSE |
| 242 |
); |
| 243 |
$postTypes = array_merge( |
| 244 |
array( 'post', 'page' ), |
| 245 |
get_post_types( $opts ) |
| 246 |
); |
| 247 |
|
| 248 |
$posts = []; |
| 249 |
foreach( $postTypes as $type ) { |
| 250 |
$posts = array_merge( $posts, get_posts( array( |
| 251 |
'posts_per_page' => -1, |
| 252 |
'post_type' => $type |
| 253 |
) ) ); |
| 254 |
} |
| 255 |
sort( $posts ); |
| 256 |
|
| 257 |
/*============================ |
| 258 |
* Find images, src, alt tags. |
| 259 |
*============================*/ |
| 260 |
$imgElemRegex = '/<img[^>]*>/'; |
| 261 |
$site_url = site_url(); |
| 262 |
$finds = []; |
| 263 |
foreach( $posts as $post ) { |
| 264 |
$post_link = get_permalink( $post ); |
| 265 |
$post_title = get_the_title( $post ); |
| 266 |
$post_edit_link = get_edit_post_link( $post ); |
| 267 |
$found = preg_match_all( |
| 268 |
$imgElemRegex, |
| 269 |
apply_filters( 'the_content', $post->post_content ), |
| 270 |
$matches, |
| 271 |
PREG_PATTERN_ORDER |
| 272 |
); |
| 273 |
|
| 274 |
if ( ! $found ) continue; |
| 275 |
|
| 276 |
foreach( $matches as $match ) { |
| 277 |
foreach( $match as $submatch ) { |
| 278 |
preg_match( '/src="([^"]*)"/', $submatch, $img_url ); |
| 279 |
if ( strpos( $img_url[ 1 ], $site_url ) !== FALSE ) |
| 280 |
$media_link = $site_url .'/wp-admin/upload.php?s=' . self::getImageNameFromUrl( $img_url[ 1 ] ); |
| 281 |
else |
| 282 |
$media_link = ''; |
| 283 |
|
| 284 |
preg_match( '/alt="([^"]*)"/', $submatch, $alt_tag ); |
| 285 |
if ( ! $alt_tag ) |
| 286 |
$alt_tag = [ '', 'MISSING' ]; |
| 287 |
else if ( $alt_tag[1] == '' ) |
| 288 |
$alt_tag = [ '', 'EMPTY' ]; |
| 289 |
|
| 290 |
$finds[] = array( |
| 291 |
'post_id' => $post->ID, |
| 292 |
'post_type' => $post->post_type, |
| 293 |
'page_title' => html_entity_decode( $post_title ), |
| 294 |
'page_url' => html_entity_decode( $post_link ), |
| 295 |
'image_url' => html_entity_decode( $img_url[1] ), |
| 296 |
'alt' => html_entity_decode( $alt_tag[1] ), |
| 297 |
'edit_link' => html_entity_decode( $post_edit_link ), |
| 298 |
'media_link' => html_entity_decode( $media_link ) |
| 299 |
); |
| 300 |
} |
| 301 |
} |
| 302 |
} |
| 303 |
|
| 304 |
return $finds; |
| 305 |
} |
| 306 |
|
| 307 |
/** |
| 308 |
* Assemble and return the CSV file contents. |
| 309 |
* |
| 310 |
* Returned (not echoed) so it can serve as an Abilities API |
| 311 |
* execute_callback as well as backing the AJAX download. |
| 312 |
* |
| 313 |
* @return string CSV content, rows separated by CRLF. |
| 314 |
*/ |
| 315 |
public static function buildCsvString() { |
| 316 |
$columns = self::csvColumns(); |
| 317 |
$keys = array_keys( $columns ); |
| 318 |
|
| 319 |
$rows = array( implode( ',', array_values( $columns ) ) ); |
| 320 |
|
| 321 |
foreach( self::buildRows() as $find ) { |
| 322 |
$ordered = array(); |
| 323 |
foreach( $keys as $key ) { |
| 324 |
$ordered[] = $find[ $key ]; |
| 325 |
} |
| 326 |
$rows[] = implode( ',', self::escapeCsv( $ordered ) ); |
| 327 |
} |
| 328 |
|
| 329 |
return implode( "\r\n", $rows ); |
| 330 |
} |
| 331 |
|
| 332 |
/** |
| 333 |
* Abilities API execute_callback: the audit as a structured JSON object. |
| 334 |
* |
| 335 |
* Wrapping the rows in an object keeps the output conformant with the MCP |
| 336 |
* structured-output contract (object outputSchema + structuredContent), |
| 337 |
* which a bare array or string could not satisfy. |
| 338 |
* |
| 339 |
* @return array{rows: array[]} |
| 340 |
*/ |
| 341 |
public static function exportAltText() { |
| 342 |
return array( 'rows' => self::buildRows() ); |
| 343 |
} |
| 344 |
|
| 345 |
/** |
| 346 |
* AJAX handler: verify the nonce and stream the CSV back to the browser. |
| 347 |
* |
| 348 |
* @since 0.0.1 |
| 349 |
*/ |
| 350 |
public static function getCsv() { |
| 351 |
check_ajax_referer( 'np_alt_tools_secure_me', 'np_alt_tools_nonce' ); |
| 352 |
|
| 353 |
echo self::buildCsvString(); |
| 354 |
die(); |
| 355 |
} |
| 356 |
|
| 357 |
/** |
| 358 |
* Register the ability category with the WordPress Abilities API. |
| 359 |
* |
| 360 |
* Must run on `wp_abilities_api_categories_init` — wp_register_ability_category() |
| 361 |
* refuses (with _doing_it_wrong) to run during any other action, and |
| 362 |
* wp_register_ability() rejects an ability whose category is unregistered, |
| 363 |
* so registering the category on the wrong hook silently drops the |
| 364 |
* ability too. |
| 365 |
*/ |
| 366 |
public static function registerAbilityCategories() { |
| 367 |
if ( ! function_exists( 'wp_register_ability_category' ) ) |
| 368 |
return; |
| 369 |
|
| 370 |
wp_register_ability_category( 'alt-text-tools', array( |
| 371 |
'label' => __( 'Alt Text Tools', 'alt-text-tools' ), |
| 372 |
'description' => __( 'Accessibility auditing for image alt text.', 'alt-text-tools' ), |
| 373 |
) ); |
| 374 |
} |
| 375 |
|
| 376 |
/** |
| 377 |
* Register the alt text export with the WordPress Abilities API. |
| 378 |
* |
| 379 |
* Registration is deliberately independent of the admin-menu wiring in the |
| 380 |
* constructor (which only runs for users who can already access the tool): |
| 381 |
* an ability must be registered for everyone, and the permission_callback |
| 382 |
* gates each individual invocation. The function_exists() guard keeps this |
| 383 |
* a no-op on WordPress installs without the Abilities API. |
| 384 |
*/ |
| 385 |
public static function registerAbilities() { |
| 386 |
if ( ! function_exists( 'wp_register_ability' ) ) |
| 387 |
return; |
| 388 |
|
| 389 |
wp_register_ability( 'alt-text-tools/export-alt-text', array( |
| 390 |
'label' => __( 'Export Alt Text', 'alt-text-tools' ), |
| 391 |
'description' => __( 'Read-only accessibility audit. Scans every <img> in the rendered content of all public posts, pages, and custom post types, and returns a JSON object with a "rows" array -- one entry per image occurrence, so an image used N times yields N entries. Includes external/hotlinked and decorative images. Each row\'s "alt" field holds the alt text, or the sentinel MISSING (no alt attribute) or EMPTY (alt=""). Takes no parameters.', 'alt-text-tools' ), |
| 392 |
'category' => 'alt-text-tools', |
| 393 |
'input_schema' => array( |
| 394 |
'type' => 'object', |
| 395 |
'properties' => array(), |
| 396 |
'additionalProperties' => false, |
| 397 |
), |
| 398 |
'output_schema' => array( |
| 399 |
'type' => 'object', |
| 400 |
'properties' => array( |
| 401 |
'rows' => array( |
| 402 |
'type' => 'array', |
| 403 |
'description' => __( 'One entry per image occurrence, in the order the images were found. An image used N times yields N entries.', 'alt-text-tools' ), |
| 404 |
'items' => array( |
| 405 |
'type' => 'object', |
| 406 |
'properties' => array( |
| 407 |
'post_id' => array( |
| 408 |
'type' => 'integer', |
| 409 |
'description' => __( 'ID of the post the image appears in.', 'alt-text-tools' ), |
| 410 |
), |
| 411 |
'post_type' => array( |
| 412 |
'type' => 'string', |
| 413 |
'description' => __( 'Post type slug (e.g. post, page, or a custom type).', 'alt-text-tools' ), |
| 414 |
), |
| 415 |
'page_title' => array( |
| 416 |
'type' => 'string', |
| 417 |
'description' => __( 'Title of the post.', 'alt-text-tools' ), |
| 418 |
), |
| 419 |
'page_url' => array( |
| 420 |
'type' => 'string', |
| 421 |
'description' => __( 'Permalink of the post.', 'alt-text-tools' ), |
| 422 |
), |
| 423 |
'image_url' => array( |
| 424 |
'type' => 'string', |
| 425 |
'description' => __( 'Source URL of the image.', 'alt-text-tools' ), |
| 426 |
), |
| 427 |
'alt' => array( |
| 428 |
'type' => 'string', |
| 429 |
'description' => __( 'Alt text, or the sentinel MISSING (no alt attribute) or EMPTY (alt="").', 'alt-text-tools' ), |
| 430 |
), |
| 431 |
'edit_link' => array( |
| 432 |
'type' => 'string', |
| 433 |
'description' => __( 'Admin edit link for the post.', 'alt-text-tools' ), |
| 434 |
), |
| 435 |
'media_link' => array( |
| 436 |
'type' => 'string', |
| 437 |
'description' => __( 'Media library search link for the image, or an empty string for external/hotlinked images not in this site\'s media library.', 'alt-text-tools' ), |
| 438 |
), |
| 439 |
), |
| 440 |
'required' => array( 'post_id', 'post_type', 'page_title', 'page_url', 'image_url', 'alt', 'edit_link', 'media_link' ), |
| 441 |
'additionalProperties' => false, |
| 442 |
), |
| 443 |
), |
| 444 |
), |
| 445 |
'required' => array( 'rows' ), |
| 446 |
'additionalProperties' => false, |
| 447 |
), |
| 448 |
'execute_callback' => array( __CLASS__, 'exportAltText' ), |
| 449 |
'permission_callback' => array( __CLASS__, 'currentUserCanAccess' ), |
| 450 |
'meta' => array( |
| 451 |
'show_in_rest' => true, |
| 452 |
// Without these, consumers must assume the WordPress defaults |
| 453 |
// (readonly: false, destructive: true) and gate this pure read |
| 454 |
// as a destructive write. |
| 455 |
'annotations' => array( |
| 456 |
'readonly' => true, |
| 457 |
'destructive' => false, |
| 458 |
), |
| 459 |
), |
| 460 |
) ); |
| 461 |
} |
| 462 |
} |
| 463 |
|
| 464 |
add_action( 'plugins_loaded', array( 'NerdpressAltTextTools', 'init' ) ); |
| 465 |
add_action( 'wp_abilities_api_categories_init', array( 'NerdpressAltTextTools', 'registerAbilityCategories' ) ); |
| 466 |
add_action( 'wp_abilities_api_init', array( 'NerdpressAltTextTools', 'registerAbilities' ) ); |
| 467 |
|
