apollo-adminservice/src/main/java/com/ctrip/framework/apollo/adminservice/controller/NamespaceBranchController.java/NamespaceBranchController/createBranch
class NamespaceBranchController:  @PostMapping("/apps/{appId}/clusters/{clusterName}/namespaces/{namespaceName}/branches")
  public NamespaceDTO createBranch(@PathVariable String appId,
                                   @PathVariable String clusterName,
                                   @PathVariable String namespaceName,
                                   @RequestParam("operator") String operator) {

    checkNamespace(appId, clusterName, namespaceName);

    Namespace createdBranch = namespaceBranchService.createBranch(appId, clusterName, namespaceName, operator);

    return BeanUtils.transform(NamespaceDTO.class, createdBranch);
  }