Ansible中实现嵌套字典内server_node_id与random_attr_name的映射

我有如下数据结构：

"my": {
    "topology": [
        {
            "management_topology": [
                {
                    "manager_id": "999999-abcd-1111-bbb-qwerty",
                    "switch": [
                        {
                            "dc_id": "datacenter-2",
                            "id": "1111111-aaa",
                            "server_node_id": [
                                "server1",
                                "server2"
                            ],
                            "switch_name": "mgmt-switch"
                        }
                    ]
                }
            ],
            "random_attr_name": "new-mgmt-switch"
        },
        {
            "management_topology": [
                {
                    "manager_id": "999999-abcd-1111-bbb-qwerty",
                    "switch": [
                        {
                            "dc_id": "datacenter-2",
                            "id": "2222222-bbb",
                            "server_node_id": [
                                "server3",
                                "server4"
                            ],
                            "switch_name": "server-switch"
                        }
                    ]
                }
            ],
            "random_attr_name": "new-server-switch"
        },
        {
            "management_topology": [
                {
                    "manager_id": "999999-abcd-1111-bbb-qwerty",
                    "switch": [
                        {
                            "dc_id": "datacenter-2",
                            "id": "3333333-ccc",
                            "server_node_id": [
                                "server5",
                                "server6"
                            ],
                            "switch_name": "dmz-switch"
                        }
                    ]
                }
            ],
            "random_attr_name": "new-dmz-switch"
        }
    ]
}

希望生成一个字典，将每个server_node_id的值映射到对应的random_attr_name的值，预期输出：

"some_new_var": {
    "server1": "new-mgmt-switch",
    "server2": "new-mgmt-switch",
    "server3": "new-server-switch",
    "server4": "new-server-switch",
    "server5": "new-dmz-switch",
    "server6": "new-dmz-switch"
}

尝试过items2dict、nested_dict、subelements以及Jinja2模板等方法但未成功，需要指导。

可以通过循环拓扑列表，结合set_fact逐个构建目标字典，逻辑简单直接，无需复杂过滤器：

- name: 构建server到switch的映射字典
  hosts: localhost
  vars:
    my:
      topology: [
        {
          "management_topology": [
            {
              "manager_id": "999999-abcd-1111-bbb-qwerty",
              "switch": [
                {
                  "dc_id": "datacenter-2",
                  "id": "1111111-aaa",
                  "server_node_id": ["server1", "server2"],
                  "switch_name": "mgmt-switch"
                }
              ]
            }
          ],
          "random_attr_name": "new-mgmt-switch"
        },
        {
          "management_topology": [
            {
              "manager_id": "999999-abcd-1111-bbb-qwerty",
              "switch": [
                {
                  "dc_id": "datacenter-2",
                  "id": "2222222-bbb",
                  "server_node_id": ["server3", "server4"],
                  "switch_name": "server-switch"
                }
              ]
            }
          ],
          "random_attr_name": "new-server-switch"
        },
        {
          "management_topology": [
            {
              "manager_id": "999999-abcd-1111-bbb-qwerty",
              "switch": [
                {
                  "dc_id": "datacenter-2",
                  "id": "3333333-ccc",
                  "server_node_id": ["server5", "server6"],
                  "switch_name": "dmz-switch"
                }
              ]
            }
          ],
          "random_attr_name": "new-dmz-switch"
        }
      ]
  tasks:
    - name: 初始化空字典
      set_fact:
        some_new_var: {}

    - name: 遍历拓扑条目，填充映射关系
      set_fact:
        some_new_var: "{{ some_new_var | combine(item_map) }}"
      loop: "{{ my.topology }}"
      vars:
        # 生成当前拓扑条目中所有server的映射键值对
        item_map: "{{ dict(item.management_topology[0].switch[0].server_node_id | product([item.random_attr_name])) }}"

    - name: 打印结果
      debug:
        var: some_new_var

关键逻辑说明： #

1. 先初始化一个空字典some_new_var
2. 循环my.topology中的每个条目：
   • 用product过滤器把当前条目的server_node_id列表和random_attr_name（包装成单元素列表）做笛卡尔积，得到类似[("server1", "new-mgmt-switch"), ("server2", "new-mgmt-switch")]的结构
   • 用dict过滤器把笛卡尔积转换成临时字典item_map
   • 用combine过滤器把临时字典合并到some_new_var中，逐步构建完整映射

执行后就能得到你需要的字典结构。

内容的提问来源于stack exchange，提问作者piercjs