Controller/Adminhtml/FastlyCdn/Backend/GetBackends.php
public function execute()
    {
        $result = $this->resultJson->create();
        try {
            $activeVersion = $this->getRequest()->getParam('active_version');
            $backends = $this->api->getBackends($activeVersion);

            if (!$backends) {
                return $result->setData([
                    'status'    => false,
                    'msg'       => 'Failed to check Backend details.'
                ]);
            }

            return $result->setData([
                'status'    => true,
                'backends'  => $backends
            ]);
        } catch (\Exception $e) {
            return $result->setData([
                'status'    => false,
                'msg'       => $e->getMessage()
            ]);
        }
    }
public function execute()
    {
        $result = $this->resultJson->create();
        try {
            $activeVersion = $this->getRequest()->getParam('active_version');
            $backends = $this->api->getBackends($activeVersion);

            if (!$backends) {
                return $result->setData([
                    'status'    => false,
                    'msg'       => 'Failed to check Backend details.'
                ]);
            }

            return $result->setData([
                'status'    => true,
                'backends'  => $backends
            ]);
        } catch (\Exception $e) {
            return $result->setData([
                'status'    => false,
                'msg'       => $e->getMessage()
            ]);
        }
    }
Get all backends for active version

@return $this|ResponseInterface|ResultInterface