Self-Assoc

/* FilesTable */
public function initialize(array $config)
{
    parent::initialize($config);

    $this->table('files');
    $this->displayField('name');
    $this->primaryKey('id');

    $this->addBehavior('Timestamp');

    $this->hasMany('SubFolders', [
        'className' => 'Files',
        'foreignKey' => 'parent_folder_id',
    ]);
    $this->belongsTo('ParentFolders', [
        'className' => 'Files',
        'foreignKey' => 'parent_folder_id',
    ]);
    $this->belongsTo('MimeTypes', [
        'foreignKey' => 'mime_type_id',
        'joinType' => 'INNER'
    ]);
    $this->belongsToMany('Messages', [
        'foreignKey' => 'file_id',
        'targetForeignKey' => 'message_id',
        'joinTable' => 'files_messages'
    ]);
    $this->belongsToMany('Users', [
        'foreignKey' => 'file_id',
        'targetForeignKey' => 'user_id',
        'joinTable' => 'files_users'
    ]);
}



/* Fetching */
public function index()
{
    $this->viewBuilder()->template('home');
    $this->loadModel('Files');

    $folders = $this->Files->find()->where([
        'Files.is_dir' => 1,
        'Files.parent_folder_id IS NULL'
    ])->order([
        'Files.filename' => 'ASC'
    ])->contain(['SubFolders']);

    debug($folders->toArray());
    $this->set(compact('folders'));
}