Devise\Pages\PagesRepository::findTemplateVariables PHP Method

    public function findTemplateVariables($templates)
    {
        $variables = [];
        $templates = is_array($templates) ? $templates : array($templates);
        $config = $this->Config->get('devise.templates');
        foreach ($templates as $template) {
            $templateConfig = isset($config[$template]) ? $config[$template] : [];
            $templateVars = isset($templateConfig['vars']) ? array_keys($templateConfig['vars']) : [];
            $variables = array_merge($variables, $templateVars);
        }
        return $variables;
    }