How does Laravel optional() work?

Question

When creating new models, I am trying to use the optional() helper to assign values when they are set. However, when the user object isn't set in this context, I receive this error: "Undefined property: stdClass::$user"

$this->events()->create([
    'category_a' => optional($event)->categoryA,
    'category_b' => optional($event)->categoryB,
    'user' => optional($event->user)->accountId,
]);

To clarify, the $event is always set, however it can contain different values. Sometimes category_a is set, sometimes category_b is set. The optional helper seems to do the trick here. But, when the object is deeper than one level, it throws an error.

So how do I work with the optional helper correctly using deeper than one level objects?

Answer 1

Also, bear in mind that in PHP 8+ you can use the null safe operator to have the same behavior with cleaner look:

// PHP 8+
$this->events()->create([
    'category_a' => $event?->categoryA,
    'category_b' => $event?->categoryB,
    'user' => $event->user?->accountId,
]);

It is also chainable and can be used with methods:

// before PHP 8
$country = null;
if ($session !== null) {
    $user = $session->user;
    if ($user !== null) {
        $address = $user->getAddress();
        if ($address !== null) {
            $country = $address->country;
        }
    }
}

// PHP 8+
$country = $session?->user?->getAddress()?->country;