Recurly_Invoice::uriForInvoice PHP Method

    protected static function uriForInvoice($invoiceNumber)
    {
        return Recurly_Client::PATH_INVOICES . '/' . rawurlencode($invoiceNumber);
    }

 protected function uri()
 {
     if (!empty($this->_href)) {
         return $this->getHref();
     } else {
         if (!empty($this->invoice_number)) {
             return Recurly_Invoice::uriForInvoice($this->invoice_number);
         } else {
             throw new Recurly_Error("Invoice number not specified");
         }
     }
 }