Adds a custom field to the attendee details sent to Zapier through Event Automator

tec_automator_attendee_add_custom_field.php

/**
 * Adds a custom field to the attendee details sent to Zapier through Event Automator.
 * Replace %%CUSTOMFIELD%% with your field name.
 *
 * @since 1.0.0
 *
 * @param array<string|mixed> An array of attendee mapped details.
 * @param array<string|mixed> An array of raw attendee details.
 */
function tec_automator_map_attendee_details( array $next_attendee, array $attendee ) {
	$custom_field = get_post_meta( $attendee['attendee_id'], '%%CUSTOMFIELD%%', true );
	if ( ! $custom_field ) {
		return $next_attendee;
	}

	$next_attendee['%%CUSTOMFIELD%%'] = $custom_field;

	return $next_attendee;
}

add_filter( 'tec_automator_map_attendee_details', 'tec_automator_attendee_add_custom_field', 10, 2 );