Build relations for FAL

/**
     * Build relations for FAL
     *
     * @param int $newStorageUid //The UID of the  model
     * @param array $file //The file model of the image
     * @param string $field //the name of the relation field
     * @param string $table //the table of the model
     */
    public function buildRelations($newStorageUid, $file, $field, $table)
    {

        $data = [];
        $data['sys_file_reference']['NEW1234'] = [
          'uid_local' => $file->getUid(),
          'uid_foreign' => $newStorageUid, // uid of your content record or own model
          'tablenames' => $table, //tca table name
          'fieldname' => $field, //see tca for fieldname
          'pid' => $this->storagePid,
          'table_local' => 'sys_file',
        ];
        $data[$table][$newStorageUid] = [$field => 'NEW1234'];



        /** @var \TYPO3\CMS\Core\DataHandling\DataHandler $tce */
        $tce = \TYPO3\CMS\Core\Utility\GeneralUtility::makeInstance('TYPO3\CMS\Core\DataHandling\DataHandler'); // create TCE instance
        $tce->start($data, []);
        $tce->process_datamap();
    }