Laravel Carbon optional parameter

Question

I have a function which communicates with external API, and would like it to pass in optional parameters as a Carbon instance, however API wants a Y-m-d format so I've done this:

protected function boostsAPIRequest($token, Carbon $dateFrom = null, Carbon $dateTo = null)
{
    try {
        $boosts = $this->httpGetRequest($token,
            $this->apiURL . 'stats/api/v1.0/boosts' . '/?date_from=' . $dateFrom->format('Y-m-d') . '&date_to=' . $dateTo->format('Y-m-d'));
        //session()->put('boosts', $boosts);
    } catch (ClientException $e) {
        $this->errorHandling($e);
    }
    return $boosts ?? null;
}

this gives me an error saying

Call to a member function format() on null

Is there a way to keep it empty if no parameter was passed in?

Answer 1

Instead of:

$dateFrom->format('Y-m-d') . '&date_to=' . $dateTo->format('Y-m-d')

use should use:

($dateFrom ? $dateFrom->format('Y-m-d') : '') . '&date_to=' . ($dateTo ? $dateTo->format('Y-m-d') : '')

this is because you cannot run format method on non-object (null in this case)