migrate-entities.php

<?php
$fh = STDIN;

while (!feof($fh)) {
	$command = json_decode(fgets($fh));

	if(!is_object($command)) {
		exit;
	}

	$body = json_decode(fgets($fh));

	if(!is_object($body)) {
		throw new Exception('Invalid body');
		
	}

	if(empty($command->index->_type)) {
		throw new Exception('Missing type');
	}

	if($command->index->_type === 'amassetversion') {

		if(empty($body->am_asset_id)) {
			throw new Exception('missing value for "am_asset_id"');
		}

		$command->index->_parent = $body->am_asset_version;
	}

	echo json_encode($command), PHP_EOL;
	echo json_encode($body), PHP_EOL;
}

echo PHP_EOL;