Neos\Flow\Security\Cryptography\HashService::getEncryptionKey PHP Method

    protected function getEncryptionKey()
    {
        if ($this->encryptionKey === null) {
            $this->encryptionKey = $this->cache->get('encryptionKey');
        }
        if ($this->encryptionKey === false && file_exists(FLOW_PATH_DATA . 'Persistent/EncryptionKey')) {
            $this->encryptionKey = file_get_contents(FLOW_PATH_DATA . 'Persistent/EncryptionKey');
        }
        if ($this->encryptionKey === false) {
            $this->encryptionKey = bin2hex(Utility\Algorithms::generateRandomBytes(48));
            $this->cache->set('encryptionKey', $this->encryptionKey);
        }
        return $this->encryptionKey;
    }