Jet Engine, Dynamic Repeater: add new filter to allowed repeater filters

jet-engine-repeater-filter-only-url.php

<?php

add_filter( 'jet-engine/listings/filters-list', 'jet_add_pdf_link_filter' );

/**
 * Add 'get_pdf_link' to allowed filters list
 *
 * @param  array $filters Registered filters
 * @return array
 */
function jet_add_pdf_link_filter( $filters ) {
	
	$filters['get_pdf_link'] = array(
		'cb' => 'jet_get_pdf_link_by_id',
		'args' => false,
	);

	return $filters;
}

/**
 * Filter callback
 *
 * @param  int $attachment_id Attachment ID
 * @return string
 */
function jet_get_pdf_link_by_id( $attachment_id ) {
	return wp_get_attachment_url( $attachment_id );
}

jet-engine-repeater-filter.php

<?php

add_filter( 'jet-engine/listings/filters-list', 'jet_add_pdf_link_filter' );

/**
 * Add 'get_pdf_link' to allowed filters list
 *
 * @param  array $filters Registered filters
 * @return array
 */
function jet_add_pdf_link_filter( $filters ) {

	$filters['get_pdf_link'] = array(
		'cb' => 'jet_get_pdf_link_by_id',
		'args' => false,
	);

	return $filters;

}

/**
 * Filter callback
 *
 * @param  int $attachment_id Attachment ID
 * @return string
 */
function jet_get_pdf_link_by_id( $attachment_id ) {

	return sprintf(
		'<a href="%1$s">%2$s</a>',
		wp_get_attachment_url( $attachment_id ),
		basename( get_attached_file( $attachment_id ) )
	);

}