Ansible：按特定字段比較兩個數組

Question

我有兩個帶有應用程序描述的數組：

source_array:
  - status: Active
    AppName": "Application 1"
    version: "0.1.1"
    metadata: ""
  - status": "Active"
    AppName: "Application 2"
    version: "0.2.2"
    metadata: "ID123"
  - status: "Active"
    AppName: "Application 3"
    version: "0.3.3"
    metadata: ""

和：

target_array:
  - status: "Active"
    AppName: "Application 1"
    version: "0.1.1"
    metadata: ""
  - status: "Active"
    AppName: "Application 2"
    version: "0.2.2"
    metadata: "ID321"
  - status: "Active",
    AppName: "Application 3"
    version: "0.3.0"
    metadata: ""

我需要根據版本字段比較這兩個數組。 因此，例如，期望的結果應該是：

[{
    "status": "Active",
    "AppName": "Application 3",
    "version": "0.3.0",
    "metadata": ""
}]

我試過使用差異過濾器，但它也返回secondf元素 - 因為它有不同的元數據

- name: Comparing arrays
  set_fact:
    delta: "{{ source_array | difference(target_array) }}"

而且我的結果不正確：

[{
    "status": "Active",
    "AppName": "Application 2",
    "version": "0.2.2",
    "metadata": "ID123"
},
{
    "status": "Active",
    "AppName": "Application 3",
    "version": "0.3.3",
    "metadata": ""
},
{
    "status": "Active",
    "AppName": "Application 2",
    "version": "0.2.2",
    "metadata": "ID321"
},
{
    "status": "Active",
    "AppName": "Application 3",
    "version": "0.3.0",
    "metadata": ""
}]

任何幫助將非常感謝！

Answer 1

這確實不是微不足道的。 您沒有提供太多上下文，但我懷疑您想要做的是檢查應用程序是否已經或應該更新。 對 ？

這是一種方式：

- hosts: localhost
  vars:
    array1:
      - status: "Active"
        AppName: "Application 1"
        version: "0.1.1"
        metadata: ""
      - status: "Active"
        AppName: "Application 2"
        version: "0.2.2"
        metadata: "ID321"
      - status: "Active"
        AppName: "Application 3"
        version: "0.3.3"
        metadata: ""
    array2:
      - status: "Active"
        AppName: "Application 1"
        version: "0.1.1"
        metadata: ""
      - status: "Active"
        AppName: "Application 2"
        version: "0.2.2"
        metadata: "ID321"
      - status: "Active"
        AppName: "Application 3"
        version: "0.3.0"
        metadata: ""

  tasks:
    - name: "Show matching pattern"
      debug:
        msg: "{{'^' + (array1|map(attribute='version'))|difference(array2|map(attribute='version'))|join('|') + '$'}}"

    - name: "Compare arrays"
      debug:
        msg: "{{ array1 | selectattr('version', 'match', '^' + (array1|map(attribute='version'))|difference(array2|map(attribute='version'))|join('|') + '$') | list }}"

它的工作原理是首先找到“更新版本”，然后根據這些版本篩選原始列表。 但它有點脆弱原因：

• 它假定你現在， 先驗哪個數組包含“更新”的數據（這里所有更新的版本都在array1 ）。
• 如果你的數組中有兩個或多個具有相同版本的元素，它將保留兩者，而不知道選擇哪個。

也許你應該考慮一個不同的數據結構，比如映射（dict）。 請參閱下面的current_state變量：

- hosts: localhost
  vars:
    current_state:
      "Application 1":
        status: "Active"
        version: "0.1.1"
        metadata: ""
      "Application 2":
        status: "Active"
        version: "0.2.2"
        metadata: "ID321"
      "Application 3":
        status: "Active"
        version: "0.3.0"
        metadata: ""
    new_applications:
      - status: "Active"
        AppName: "Application 1"
        version: "0.1.1"
        metadata: ""
      - status: "Active"
        AppName: "Application 2"
        version: "0.2.2"
        metadata: "ID321"
      - status: "Active"
        AppName: "Application 3"
        version: "0.3.3"
        metadata: ""
      - status: "Active"
        AppName: "Application 4"
        version: "0.1.0"
        metadata: ""
  tasks:
    - name: "Different appraoch"
      debug:
         msg: "{{ item.0 }} -- {{ item.1 }} -- Should update: {{ item.1.version is version((current_state[item.0]|default({'version': '0.0.0'}))['version'], '>') }}"
      loop: "{{ new_applications|map(attribute='AppName')|zip(new_applications)|list }}"

    - name: "Build 'current_state' from a list (if not available as is)"
      # There might be a smarter way using items2dict...
      set_fact:
        dict_from_list: "{{ dict_from_list|default({})|combine({item[0]: item[1]})}}"
      loop: "{{ new_applications|map(attribute='AppName')|zip(new_applications)|list }}"

    - debug:
        var: dict_from_list

此版本修復了上述兩個問題中的最后一個問題。 如果兩個數組的順序不相同，或者數組的長度不同，則它也更加健壯。

我選擇忽略的第一個問題，因為盡管你的問題導致相信array1和array2可以互換，但我假設它們實際上不是在給定的上下文中。