Get the Slugs for All Fields in an Advanced Custom Fields Flexible Content Field

get-the-slugs-for-all-fields-in-an-advanced-custom-fields-flexible-content-field.php

<?php

/**
 * Get the slugs for all fields in an ACF Flexible Content field.
 *
 * @param  string $flexible_content_slug The slug of the Flexible Content field.
 * @param  int    $post_id               (optional) The ID of the post. Default is current post ID.
 * @return array                         The field slugs. Emtpy array on error or if there are no fields.
 */
function km_get_all_field_slugs_in_acf_flexible_content_field( $flexible_content_slug, $post_id = null ) {

	$post_id                = $post_id ?: get_the_ID();
	$flexible_content_field = get_field( $flexible_content_slug, $post_id );

	if ( ! is_array( $flexible_content_field ) ) {
		return array();
	}

	return wp_list_pluck( $flexible_content_field, 'acf_fc_layout' );
}