Lorsque je lance un composer update
je reçois ce message d'erreur:
Loading composer repositories with package information
Updating dependencies (including require-dev)
Failed to download psr/log from dist: The zip extension and unzip command are both missing, skipping.
The php.ini used by your command-line PHP is: /etc/php/7.0/cli/php.ini
Now trying to download from source
Que dois-je faire pour activer les commandes zip et unzip afin que composer puisse télécharger des dépendances?