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<?php |
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/** |
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* Module Name: Canonical URLs |
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* Module Description: Add canonical URL tags to archive pages to prevent duplicate content in search engines. |
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* Sort Order: 36 |
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* First Introduced: 15.6 |
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* Requires Connection: No |
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* Requires User Connection: No |
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* Auto Activate: No |
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* Module Tags: Traffic |
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* Feature: Traffic |
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* Additional Search Queries: canonical, seo, duplicate content, woocommerce, archive |
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* |
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* @package automattic/jetpack |
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*/ |
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|
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if ( ! defined( 'ABSPATH' ) ) { |
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exit( 0 ); |
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} |
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|
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// Disable canonical URL output when a conflicting SEO plugin is active. |
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add_filter( 'jetpack_disable_canonical_urls', 'jetpack_canonical_urls_check_conflicts' ); |
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|
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/** |
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* Can be used to prevent the Canonical URLs module from outputting canonical tags. |
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* |
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* @module canonical-urls |
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* |
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* @since 15.6 |
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* |
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* @param bool $disabled Whether canonical URL output is disabled. Defaults to false. |
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*/ |
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if ( ! apply_filters( 'jetpack_disable_canonical_urls', false ) ) { |
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require_once __DIR__ . '/canonical-urls/class-jetpack-canonical-urls-resolver.php'; |
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add_action( 'wp_head', 'jetpack_canonical_urls_output_tag' ); |
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} |
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|
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/** |
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* Check if a conflicting SEO plugin is active and disable canonical URL output. |
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* |
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* @since 15.6 |
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* |
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* @param bool $disabled Whether canonical URL output is already disabled. |
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* @return bool Whether canonical URL output should be disabled. |
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*/ |
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function jetpack_canonical_urls_check_conflicts( $disabled ) { |
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if ( $disabled ) { |
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return $disabled; |
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} |
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|
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$conflicting_plugins = array( |
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'wordpress-seo/wp-seo.php', |
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'wordpress-seo-premium/wp-seo-premium.php', |
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'all-in-one-seo-pack/all_in_one_seo_pack.php', |
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'all-in-one-seo-pack-pro/all_in_one_seo_pack.php', |
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'seo-by-rank-math/rank-math.php', |
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'autodescription/autodescription.php', |
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'slim-seo/slim-seo.php', |
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'wp-seopress/seopress.php', |
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'wp-seopress-pro/seopress-pro.php', |
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'seo-key/seo-key.php', |
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'seo-key-pro/seo-key.php', |
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); |
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|
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foreach ( $conflicting_plugins as $plugin ) { |
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if ( Jetpack::is_plugin_active( $plugin ) ) { |
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return true; |
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} |
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} |
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|
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return $disabled; |
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} |
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|
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/** |
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* Output the canonical link tag for non-singular pages. |
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* |
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* WordPress core handles singular posts/pages via rel_canonical(), |
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* so this function only outputs canonical tags for archive pages. |
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* |
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* @since 15.6 |
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*/ |
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function jetpack_canonical_urls_output_tag() { |
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if ( is_singular() ) { |
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return; |
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} |
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|
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$url = Jetpack_Canonical_Urls_Resolver::get_canonical_url(); |
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|
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if ( ! empty( $url ) ) { |
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echo '<link rel="canonical" href="' . esc_url( $url ) . '" />' . "\n"; |
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} |
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} |
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|
