Doctrine\ODM\MongoDB\Mapping\Driver\AnnotationDriver::setShardKey PHP Method

    private function setShardKey(ClassMetadataInfo $class, ODM\ShardKey $shardKey)
    {
        $options = array();
        $allowed = array('unique', 'numInitialChunks');
        foreach ($allowed as $name) {
            if (isset($shardKey->{$name})) {
                $options[$name] = $shardKey->{$name};
            }
        }
        $class->setShardKey($shardKey->keys, $options);
    }