APS package installation_task stuck in ISPConfig3

When trying to install an APS package on a ISPConfig3 system, the package was never installed and the status “installation_task” remained for the site I tried to install a package.

Investigating /var/log/ispconfig/cron.log revealed:

PHP Fatal error: Uncaught Error: Call to undefined function curl_init() in /usr/local/ispconfig/server/lib/classes/aps_installer.inc.php:627

This problem can occur when curl is not installed on the target server, but that was not the problem in this case.

The server had been upgraded to Ubuntu 16.05 which runs PHP 7.0 instead of PHP 5. Curl was installed but the problem was that php7.0-curl was missing. The problem was resolved by:

sudo apt-get install php7.0-curl

The next issue that occured according to the logs was:

PHP Fatal error: Uncaught Error: Class 'ZipArchive' not found in /usr/local/ispconfig/server/lib/classes/aps_installer.inc.php:106

This problem was resolved by:

sudo apt-get install php7.0-zip

After this nothing more had to be done. The ISPConfig cron now successfully installed the APS package automatically.