Controller/Adminhtml/FastlyCdn/Edge/Acl/GetAcl.php
public function execute()
    {
        $result = $this->resultJson->create();

        try {
            $service = $this->api->checkServiceDetails();
            if (!$service) {
                return $result->setData([
                    'status'    => false,
                    'msg'       => 'Failed to check Service details.'
                ]);
            }

            return $result->$this->acl->determineVersions($service->versions);
        } catch (\Exception $e) {
            return $result->setData([
                'status'    => false,
                'msg'       => $e->getMessage()
            ]);
        }
    }
public function execute()
    {
        $result = $this->resultJson->create();

        try {
            $service = $this->api->checkServiceDetails();
            if (!$service) {
                return $result->setData([
                    'status'    => false,
                    'msg'       => 'Failed to check Service details.'
                ]);
            }

            return $result->$this->acl->determineVersions($service->versions);
        } catch (\Exception $e) {
            return $result->setData([
                'status'    => false,
                'msg'       => $e->getMessage()
            ]);
        }
    }
Get ACL

@return $this|\Magento\Framework\App\ResponseInterface|\Magento\Framework\Controller\ResultInterface