Humhub 1.16.0 - Error with PolymorphicRelation::getPolymorphicRelation()

[marc-farre]

What steps will reproduce the problem?

I cannot tell, but on my Humhub instance, it occurred when viewing the notification list.

The problem is that $this->owner->getAttribute() can return null:

humhub/protected/humhub/components/behaviors/PolymorphicRelation.php

Line 70 in 1db793d

$this->owner->getAttribute($this->classAttribute),

But the first argument of static::loadActiveRecord() must be a string:
https://github.com/humhub/humhub/blob/1db793da1f0d680053713b0654bdd5f32a5339cd/protected/humhub/components/behaviors/PolymorphicRelation.php#L177C50-L177C50

Additional info

Log:

TypeError: humhub\components\behaviors\PolymorphicRelation::loadActiveRecord(): Argument #1 ($className) must be of type string, null given, called in /var/www/humhub/protected/humhub/components/behaviors/PolymorphicRelation.php on line 69 and defined in /var/www/humhub/protected/humhub/components/behaviors/PolymorphicRelation.php:177
Stack trace:
#0 /var/www/humhub/protected/humhub/components/behaviors/PolymorphicRelation.php(69): humhub\components\behaviors\PolymorphicRelation::loadActiveRecord(NULL, NULL)
#1 [internal function]: humhub\components\behaviors\PolymorphicRelation->getPolymorphicRelation()
#2 /var/www/humhub/protected/vendor/yiisoft/yii2/base/Component.php(297): call_user_func_array(Array, Array)
#3 /var/www/humhub/protected/humhub/modules/notification/models/Notification.php(130): yii\base\Component->__call('getPolymorphicR...', Array)
#4 /var/www/humhub/protected/humhub/modules/notification/controllers/ListController.php(46): humhub\modules\notification\models\Notification->getBaseModel()
#5 [internal function]: humhub\modules\notification\controllers\ListController->actionIndex()
#6 /var/www/humhub/protected/vendor/yiisoft/yii2/base/InlineAction.php(57): call_user_func_array(Array, Array)
#7 /var/www/humhub/protected/vendor/yiisoft/yii2/base/Controller.php(178): yii\base\InlineAction->runWithParams(Array)
#8 /var/www/humhub/protected/vendor/yiisoft/yii2/base/Module.php(552): yii\base\Controller->runAction('', Array)
#9 /var/www/humhub/protected/vendor/yiisoft/yii2/web/Application.php(103): yii\base\Module->runAction('notification/li...', Array)
#10 /var/www/humhub/protected/vendor/yiisoft/yii2/base/Application.php(384): yii\web\Application->handleRequest(Object(humhub\components\Request))
#11 /var/www/humhub/index.php(28): yii\base\Application->run()
#12 {main}

Q	A
HumHub version	1.16.0
PHP version	8.2

[marc-farre]

@martin-rueegg I think it's a code you've worked one. Maybe you know what would be the best approach to solve this problem. (allowing a null param or forcing null to become a string). Thanks!

[ArchBlood]

I've not tested;

$classAttributeValue = $this->owner?->getAttribute($this->classAttribute);

if ($classAttributeValue !== null) {
    $record = static::loadActiveRecord($classAttributeValue);
} else {
    // Handle the case where $classAttributeValue is null
    $record = null;
}

[martin-rueegg]

I guess if $this->owner->getAttribute($this->classAttribute) returns an empty value (no matter if null or '', we should not attempt to load the active record. Same applies for $this->owner->getAttribute($this->pkAttribute). Because without both of these information we cannot find the any ActiveRecord. We should set $record to null in such a case:

So yes, removing the type restriction is probably the easiest option:

• Fix: polymorphic relation lookup (Fix #6772) #6773

[martin-rueegg]

I've not tested;

$classAttributeValue = $this->owner?->getAttribute($this->classAttribute);

if ($classAttributeValue !== null) {
    $record = static::loadActiveRecord($classAttributeValue);
} else {
    // Handle the case where $classAttributeValue is null
    $record = null;
}

Thanks, @ArchBlood, for your suggestion. According to the exception trace provided by @marc-farre it is not an issue that $this->owner is not set (must be set for a behaviour!), but that the getAttribute() returns a null value.

I'm not sure we need to account for the possibility, that for some reason the owner is set to null, should we? It's a public property and some idiot could have the idea to set it to null ... :-D

Also, the Nullsafe operator is only available since php 8.0. And while @luke- said he wants to silantly fade out v7.4, this would simply crash it ... :-)

[ArchBlood]

Also, the Nullsafe operator is only available since php 8.0. And while @luke- said he wants to silantly fade out v7.4, this would simply crash it ... :-)

I can understand that, some of @GreenMeteor modules will not function unless PHP 8.0 are used, others still need updated for PHP 8.0, but I can understand the silent method of moving away from PHP 7.4. 🤔