In PHP 8.1 the return type of jsonSerialize() was set to mixed, and a "deprecated" notice is raised if subclasses do not declare any return type. mixed was added in PHP 8.0, but the return type of a method can have a more specific type in a subclass than in the parent class (https://wiki.php.net/rfc/mixed_type_v2), so array can be used to solve the deprecated notice while also being compatible with PHP 7.4.
How to test
Use PHP 8.1
Maybe set error_reporting to E_ALL in /etc/php/8.1/... for your web server (find /etc/php -type f -exec grep -Hn error_reporting {} \;)
apt-get install clamav clamav-daemon (or equivalent for your distribution)
freshclam
service clamav-daemon start
Enable files_antivirus in Nextcloud
In Security administration settings, set the mode of the antivirus to ClamAV Daemon (socket)
Open the advanced settings so the rules are set
Save the settings
(Showing the settings should have been enough to raise the notice, but the following steps are the typical scenario that raises it)
Create a public upload folder
As a guest, upload a file
Result with this pull request
No errors are shown in Nextcloud log
Result without this pull request
Return type of OCA\Files_Antivirus\Db\Rule::jsonSerialize() should either be compatible with JsonSerializable::jsonSerialize(): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the notice is shown in Nextcloud log
Fixes #258
In PHP 8.1 the return type of
jsonSerialize()was set tomixed, and a "deprecated" notice is raised if subclasses do not declare any return type.mixedwas added in PHP 8.0, but the return type of a method can have a more specific type in a subclass than in the parent class (https://wiki.php.net/rfc/mixed_type_v2), soarraycan be used to solve the deprecated notice while also being compatible with PHP 7.4.How to test
error_reportingtoE_ALLin/etc/php/8.1/...for your web server (find /etc/php -type f -exec grep -Hn error_reporting {} \;)apt-get install clamav clamav-daemon(or equivalent for your distribution)freshclamservice clamav-daemon startfiles_antivirusin NextcloudClamAV Daemon (socket)Result with this pull request
No errors are shown in Nextcloud log
Result without this pull request
Return type of OCA\Files_Antivirus\Db\Rule::jsonSerialize() should either be compatible with JsonSerializable::jsonSerialize(): mixed, or the #[\ReturnTypeWillChange] attribute should be used to temporarily suppress the noticeis shown in Nextcloud log