apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/controller/NamespaceBranchController.java/NamespaceBranchController/findBranch
class NamespaceBranchController:  @GetMapping("/apps/{appId}/envs/{env}/clusters/{clusterName}/namespaces/{namespaceName}/branches")
  public NamespaceBO findBranch(@PathVariable String appId,
                                @PathVariable String env,
                                @PathVariable String clusterName,
                                @PathVariable String namespaceName) {
    NamespaceBO namespaceBO = namespaceBranchService.findBranch(appId, Env.valueOf(env), clusterName, namespaceName);

    if (namespaceBO != null && permissionValidator.shouldHideConfigToCurrentUser(appId, env, namespaceName)) {
      namespaceBO.hideItems();
    }

    return namespaceBO;
  }