getEsi example

case 'isocode':
                return $this->getId();
            case 'skipbackend':
                return $this->getDefault() ? 1 : 0;
            case 'parentID':
                if (!$this->getCategory() instanceof Category) {
                    throw new RuntimeException('Shop does not have a parent category set');
                }

                return $this->getCategory()->getId();
            case 'esi':
                return $this->getTemplate() !== null ? $this->getTemplate()->getEsi() : false;
            case 'navigation':
                return $this->getPages();
            case 'defaultcustomergroup':
                return $this->getCustomerGroup()->getKey();
            case 'defaultcurrency':
                return $this->getCurrency()->getId();
            case 'fallback':
                return $this->getFallback() !== null ? $this->getFallback()->getId() : null;
        }

        return null;
    }