Multisite adjust uploads like (/upload/%alphanumeric_id%/%file_type%/%blog_ID%)

Ok this is my solution for now – but how do I add the generated alphanumeric_id as add_post_meta($post_id, 'alphanumeric_id', $randomString); to the related attachment?

/*===================================================================================*/
/*  function change the upload for multi-lang
/*==================================================================================*/


function bZive_handle_upload_prefilter( $file ) {

    add_filter('upload_dir', 'bZive_custom_upload_dir');
    return $file;
}


function bZive_handle_upload( $fileinfo ){

    remove_filter('upload_dir', 'bZive_custom_upload_dir');
    return $fileinfo;
}



/**
 * Force all network uploads to reside in "/upload", and by-pass
 * "files" URL rewrite for site-specific directories.
 * 
 * @link    http://wordpress.stackexchange.com/q/147750/1685
 * 
 * @param   array   $dirs
 * @return  array 
 */

function bZive_upload_dir( $dirs ){

    $dirs['baseurl'] = network_site_url( '/upload' );
    $dirs['basedir'] = ABSPATH . '/upload';
    $dirs['path'] = $dirs['basedir'] . $dirs['subdir'];
    $dirs['url'] = $dirs['baseurl'] . $dirs['subdir'];

    return $dirs;
}

add_filter( 'upload_dir', 'bZive_upload_dir' );



function bZive_custom_upload_dir($path){  

    /*
     * Save uploads in alphanumeric_id based folders 
     *
     */

    $postTypes = array('profile', 'article', 'attachment');
    $postType = get_post_type( $post_id );


    $characters = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNPQRSTUVWXYZ'$§%&!";

    $charactersLength = strlen($characters);
    $randomString = '';
    for ($i = 0; $i < 15; $i++) {
        $randomString .= $characters[rand(0, $charactersLength - 1)];
    }


    /*
     * Now check here if the string is in the database
     */
    $args = array(
    'post_type'     =>  array(
            $postTypes 
        ),
    'meta_query'    =>  array(
        array(
            'meta_key'  =>  'alphanumeric_id'
        )
    )
    );
    $posts = new WP_Query( $args );


    $meta_values="";
    if( $posts->have_posts() ) {
      while( $posts->have_posts() ) {
        $posts->the_post();

        $meta_values[] = get_post_meta( get_the_ID(), 'alphanumeric_id', true );
      }
    } 
    wp_reset_postdata();


    if (in_array( $randomString, $meta_values )) {
        // "Match found"
        return bZive_custom_upload_dir;

    }  else {
        // "Match not found"
        $customdir="https://wordpress.stackexchange.com/" . $randomString;



    }

    /*
     * Save uploads in blog_id based folders 
     *
     */     
    $customdir .= "https://wordpress.stackexchange.com/" . get_current_blog_id();





    $path['path']    = str_replace($path['subdir'], '', $path['path']); //remove default subdir (year/month)
    $path['url']     = str_replace($path['subdir'], '', $path['url']);      
    $path['subdir']  = $customdir;
    $path['path']   .= $customdir; 
    $path['url']    .= $customdir;  




    return $path;
}

add_filter('wp_handle_upload_prefilter', 'bZive_handle_upload_prefilter');
add_filter('wp_handle_upload', 'bZive_handle_upload');

Ok got the id like this

function bZive_generate_AlphanumericID( $post_id ) {

    $postTypes  = array('profile', 'article');
    $postType       = get_post_type( $post_id );
    $randomString   = '';



    if ( $postType == 'attachment' and empty( get_post_meta( $post_id, 'alphanumeric_id', true ) ) ) {

    $urlstring = wp_get_attachment_url( $post_id ); 
    $segments = explode("https://wordpress.stackexchange.com/", trim(parse_url($urlstring, PHP_URL_PATH), "https://wordpress.stackexchange.com/"));
    $numSegments = count($segments); 
    $randomString = $segments[1];


    add_post_meta($post_id, 'alphanumeric_id', $randomString);
    return $randomString;


    }


}
add_action('wp_insert_post', 'bZive_generate_AlphanumericID', 10, 3);
add_action('add_attachment', 'bZive_generate_AlphanumericID', 10, 1);