Definir título y metas desde un módulo en Prestashop 1.7

    public function getTemplateVarPage(){
    	$config = PsBlogConfig::getInstance(); // Probablemente tu no uses este PsBlog. Adapta estas líneas a tu entorno y caso
        if( $config->get('url_use_id', 1))
        {
            // URL HAVE ID
            $blog = new PsBlogBlog(Tools::getValue('id'), $this->context->language->id);
        }else{
            // REMOVE ID FROM URL
            $url_rewrite = explode('/', $_SERVER['REQUEST_URI']) ;
            $url_last_item = count($url_rewrite) - 1;
            $url_rewrite = rtrim($url_rewrite[$url_last_item],'.html');
            $blog = PsBlogBlog::findByRewrite(array('link_rewrite'=>$url_rewrite));
        }
        
    	$page = parent::getTemplateVarPage();

		$page['meta']['title'] = Tools::ucfirst($blog->meta_title).' - '.Configuration::get('PS_SHOP_NAME');
		$page['meta']['description'] = $blog->meta_description;
		$page['meta']['keywords'] = $blog->meta_keywords;
		$page['meta']['robots'] = 'index'; // noindex, nofollow, none, ...

    	return $page;
	}