wp_prepare_attachment_for_js

wp_prepare_attachment_for_js: 这个过滤器用来准备一个附件以便在JavaScript中使用。它被用来创建一个代表附件及其属性的JavaScript对象。

为JS准备一个附件文章对象，预计它将被JSON编码并适合附件模型。

function wp_prepare_attachment_for_js( $attachment ) {
	$attachment = get_post( $attachment );

	if ( ! $attachment ) {
		return;
	}

	if ( 'attachment' !== $attachment->post_type ) {
		return;
	}

	$meta = wp_get_attachment_metadata( $attachment->ID );
	if ( false !== strpos( $attachment->post_mime_type, '/' ) ) {
		list( $type, $subtype ) = explode( '/', $attachment->post_mime_type );
	} else {
		list( $type, $subtype ) = array( $attachment->post_mime_type, '' );
	}

	$attachment_url = wp_get_attachment_url( $attachment->ID );
	$base_url       = str_replace( wp_basename( $attachment_url ), '', $attachment_url );

	$response = array(
		'id'            => $attachment->ID,
		'title'         => $attachment->post_title,
		'filename'      => wp_basename( get_attached_file( $attachment->ID ) ),
		'url'           => $attachment_url,
		'link'          => get_attachment_link( $attachment->ID ),
		'alt'           => get_post_meta( $attachment->ID, '_wp_attachment_image_alt', true ),
		'author'        => $attachment->post_author,
		'description'   => $attachment->post_content,
		'caption'       => $attachment->post_excerpt,
		'name'          => $attachment->post_name,
		'status'        => $attachment->post_status,
		'uploadedTo'    => $attachment->post_parent,
		'date'          => strtotime( $attachment->post_date_gmt ) * 1000,
		'modified'      => strtotime( $attachment->post_modified_gmt ) * 1000,
		'menuOrder'     => $attachment->menu_order,
		'mime'          => $attachment->post_mime_type,
		'type'          => $type,
		'subtype'       => $subtype,
		'icon'          => wp_mime_type_icon( $attachment->ID ),
		'dateFormatted' => mysql2date( __( 'F j, Y' ), $attachment->post_date ),
		'nonces'        => array(
			'update' => false,
			'delete' => false,
			'edit'   => false,
		),
		'editLink'      => false,
		'meta'          => false,
	);

	$author = new WP_User( $attachment->post_author );

	if ( $author->exists() ) {
		$author_name            = $author->display_name ? $author->display_name : $author->nickname;
		$response['authorName'] = html_entity_decode( $author_name, ENT_QUOTES, get_bloginfo( 'charset' ) );
		$response['authorLink'] = get_edit_user_link( $author->ID );
	} else {
		$response['authorName'] = __( '(no author)' );
	}

	if ( $attachment->post_parent ) {
		$post_parent = get_post( $attachment->post_parent );
		if ( $post_parent ) {
			$response['uploadedToTitle'] = $post_parent->post_title ? $post_parent->post_title : __( '(no title)' );
			$response['uploadedToLink']  = get_edit_post_link( $attachment->post_parent, 'raw' );
		}
	}

	$attached_file = get_attached_file( $attachment->ID );

	if ( isset( $meta['filesize'] ) ) {
		$bytes = $meta['filesize'];
	} elseif ( file_exists( $attached_file ) ) {
		$bytes = wp_filesize( $attached_file );
	} else {
		$bytes = '';
	}

	if ( $bytes ) {
		$response['filesizeInBytes']       = $bytes;
		$response['filesizeHumanReadable'] = size_format( $bytes );
	}

	$context             = get_post_meta( $attachment->ID, '_wp_attachment_context', true );
	$response['context'] = ( $context ) ? $context : '';

	if ( current_user_can( 'edit_post', $attachment->ID ) ) {
		$response['nonces']['update'] = wp_create_nonce( 'update-post_' . $attachment->ID );
		$response['nonces']['edit']   = wp_create_nonce( 'image_editor-' . $attachment->ID );
		$response['editLink']         = get_edit_post_link( $attachment->ID, 'raw' );
	}

	if ( current_user_can( 'delete_post', $attachment->ID ) ) {
		$response['nonces']['delete'] = wp_create_nonce( 'delete-post_' . $attachment->ID );
	}

	if ( $meta && ( 'image' === $type || ! empty( $meta['sizes'] ) ) ) {
		$sizes = array();

		/** This filter is documented in wp-admin/includes/media.php */
		$possible_sizes = apply_filters(
			'image_size_names_choose',
			array(
				'thumbnail' => __( 'Thumbnail' ),
				'medium'    => __( 'Medium' ),
				'large'     => __( 'Large' ),
				'full'      => __( 'Full Size' ),
			)
		);
		unset( $possible_sizes['full'] );

		/*
		 * Loop through all potential sizes that may be chosen. Try to do this with some efficiency.
		 * First: run the image_downsize filter. If it returns something, we can use its data.
		 * If the filter does not return something, then image_downsize() is just an expensive way
		 * to check the image metadata, which we do second.
		 */
		foreach ( $possible_sizes as $size => $label ) {

			/** This filter is documented in wp-includes/media.php */
			$downsize = apply_filters( 'image_downsize', false, $attachment->ID, $size );

			if ( $downsize ) {
				if ( empty( $downsize[3] ) ) {
					continue;
				}

				$sizes[ $size ] = array(
					'height'      => $downsize[2],
					'width'       => $downsize[1],
					'url'         => $downsize[0],
					'orientation' => $downsize[2] > $downsize[1] ? 'portrait' : 'landscape',
				);
			} elseif ( isset( $meta['sizes'][ $size ] ) ) {
				// Nothing from the filter, so consult image metadata if we have it.
				$size_meta = $meta['sizes'][ $size ];

				// We have the actual image size, but might need to further constrain it if content_width is narrower.
				// Thumbnail, medium, and full sizes are also checked against the site's height/width options.
				list( $width, $height ) = image_constrain_size_for_editor( $size_meta['width'], $size_meta['height'], $size, 'edit' );

				$sizes[ $size ] = array(
					'height'      => $height,
					'width'       => $width,
					'url'         => $base_url . $size_meta['file'],
					'orientation' => $height > $width ? 'portrait' : 'landscape',
				);
			}
		}

		if ( 'image' === $type ) {
			if ( ! empty( $meta['original_image'] ) ) {
				$response['originalImageURL']  = wp_get_original_image_url( $attachment->ID );
				$response['originalImageName'] = wp_basename( wp_get_original_image_path( $attachment->ID ) );
			}

			$sizes['full'] = array( 'url' => $attachment_url );

			if ( isset( $meta['height'], $meta['width'] ) ) {
				$sizes['full']['height']      = $meta['height'];
				$sizes['full']['width']       = $meta['width'];
				$sizes['full']['orientation'] = $meta['height'] > $meta['width'] ? 'portrait' : 'landscape';
			}

			$response = array_merge( $response, $sizes['full'] );
		} elseif ( $meta['sizes']['full']['file'] ) {
			$sizes['full'] = array(
				'url'         => $base_url . $meta['sizes']['full']['file'],
				'height'      => $meta['sizes']['full']['height'],
				'width'       => $meta['sizes']['full']['width'],
				'orientation' => $meta['sizes']['full']['height'] > $meta['sizes']['full']['width'] ? 'portrait' : 'landscape',
			);
		}

		$response = array_merge( $response, array( 'sizes' => $sizes ) );
	}

	if ( $meta && 'video' === $type ) {
		if ( isset( $meta['width'] ) ) {
			$response['width'] = (int) $meta['width'];
		}
		if ( isset( $meta['height'] ) ) {
			$response['height'] = (int) $meta['height'];
		}
	}

	if ( $meta && ( 'audio' === $type || 'video' === $type ) ) {
		if ( isset( $meta['length_formatted'] ) ) {
			$response['fileLength']              = $meta['length_formatted'];
			$response['fileLengthHumanReadable'] = human_readable_duration( $meta['length_formatted'] );
		}

		$response['meta'] = array();
		foreach ( wp_get_attachment_id3_keys( $attachment, 'js' ) as $key => $label ) {
			$response['meta'][ $key ] = false;

			if ( ! empty( $meta[ $key ] ) ) {
				$response['meta'][ $key ] = $meta[ $key ];
			}
		}

		$id = get_post_thumbnail_id( $attachment->ID );
		if ( ! empty( $id ) ) {
			list( $src, $width, $height ) = wp_get_attachment_image_src( $id, 'full' );
			$response['image']            = compact( 'src', 'width', 'height' );
			list( $src, $width, $height ) = wp_get_attachment_image_src( $id, 'thumbnail' );
			$response['thumb']            = compact( 'src', 'width', 'height' );
		} else {
			$src               = wp_mime_type_icon( $attachment->ID );
			$width             = 48;
			$height            = 64;
			$response['image'] = compact( 'src', 'width', 'height' );
			$response['thumb'] = compact( 'src', 'width', 'height' );
		}
	}

	if ( function_exists( 'get_compat_media_markup' ) ) {
		$response['compat'] = get_compat_media_markup( $attachment->ID, array( 'in_modal' => true ) );
	}

	if ( function_exists( 'get_media_states' ) ) {
		$media_states = get_media_states( $attachment );
		if ( ! empty( $media_states ) ) {
			$response['mediaStates'] = implode( ', ', $media_states );
		}
	}

	/**
	 * Filters the attachment data prepared for JavaScript.
	 *
	 * @since 3.5.0
	 *
	 * @param array       $response   Array of prepared attachment data. @see wp_prepare_attachment_for_js().
	 * @param WP_Post     $attachment Attachment object.
	 * @param array|false $meta       Array of attachment meta data, or false if there is none.
	 */
	return apply_filters( 'wp_prepare_attachment_for_js', $response, $attachment, $meta );
}