apollo-adminservice/src/main/java/com/ctrip/framework/apollo/adminservice/controller/NamespaceLockController.java/NamespaceLockController/getNamespaceLockOwner
class NamespaceLockController:  @GetMapping("/apps/{appId}/clusters/{clusterName}/namespaces/{namespaceName}/lock")
  public NamespaceLockDTO getNamespaceLockOwner(@PathVariable String appId, @PathVariable String clusterName,
                                                @PathVariable String namespaceName) {
    Namespace namespace = namespaceService.findOne(appId, clusterName, namespaceName);
    if (namespace == null) {
      throw new BadRequestException("namespace not exist.");
    }

    if (bizConfig.isNamespaceLockSwitchOff()) {
      return null;
    }

    NamespaceLock lock = namespaceLockService.findLock(namespace.getId());

    if (lock == null) {
      return null;
    }

    return BeanUtils.transform(NamespaceLockDTO.class, lock);
  }