如何通过唯一的第一个和第二个字段过滤字典两次？

Question

我想从两个列表中获取字典列表，并按唯一字段进行过滤。 例如：我需要创建键值对，使两个列表中的元素都是唯一的。

我正在尝试使用嵌套循环：

- name: "Create list"
  gather_facts: false
  hosts: all

  vars:
    var1:
      - '1'
      - '2'
      - '3'
    var2:
      - 'a'
      - 'b'
      - 'c'

  tasks:

    - name: "Merge lists"
      ansible.builtin.set_fact:
        new_list: "{{ new_list | default([]) + [{'var1': (item[0] | string), 'var2': (item[1] | string)}] }}"
      loop: "{{ var1 | product(var2) | list }}"

    - name: "Print new_list"
      ansible.builtin.debug:
        msg: "{{ new_list }}"

结果如下：

[
        {
            "var1": "1",
            "var2": "a"
        },
        {
            "var1": "1",
            "var2": "b"
        },
        {
            "var1": "1",
            "var2": "c"
        },
        {
            "var1": "2",
            "var2": "a"
        },
        {
            "var1": "2",
            "var2": "b"
        },
        {
            "var1": "2",
            "var2": "c"
        },
        {
            "var1": "3",
            "var2": "a"
        },
        {
            "var1": "3",
            "var2": "b"
        },
        {
            "var1": "3",
            "var2": "c"
        }
]

我想要的结果：

[
        {
            "var1": "1",
            "var2": "a"
        },
        {
            "var1": "2",
            "var2": "b"
        },
        {
            "var1": "3",
            "var2": "c"
        }
]

我试图从this查询中找出示例，但那里的情况与我的不同。

Answer 1

根据您想要的输出，您可以简化问题，如以下演示手册所示：

---
- name: Manipulate lists
  hosts: localhost
  gather_facts: false

  vars:

    var1:
      - 1
      - 2
      - 3
    
    var2:
      - a
      - b
      - c

    new_list: >-
      {{
        dict(
          var1 | map('string') | zip(var2 | map('string'))
        ) 
        | dict2items(key_name='var1', value_name='var2')
      }}

  tasks:
    - name: Show calculated list
      debug:
        var: new_list

给出：

PLAY [Manipulate lists] *******************************************************************************************************************************************************************************************

TASK [Show calculated list] ***************************************************************************************************************************************************************************************
ok: [localhost] => {
    "new_list": [
        {
            "var1": "1",
            "var2": "a"
        },
        {
            "var1": "2",
            "var2": "b"
        },
        {
            "var1": "3",
            "var2": "c"
        }
    ]
}

PLAY RECAP ********************************************************************************************************************************************************************************************************
localhost                  : ok=1    changed=0    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0