Ansible 循环获取下一个值

Question

我目前在循环执行特定任务时遇到了一些麻烦。 首先，我需要循环特定的结构：

companies:
  - name: Facebook
    company_url: "https://www.facebook.com"
    company_certificate: "Facebook.crt"
    port_type: "AS2"
    create_filematch: "yes"
    filters:
        - name: "ORDERS"
          regex: "ORDER*"
        - name: "INVOICES"
          regex: "INVOICE*"
  - name: Google
    company_url: "https://www.google.com"
    company_certificate: "Google.crt"
    port_type: "AS2"
    create_filematch: "yes"
    filters:
        - name: "ORDERS"
          regex: "ORDER*"
        - name: "INVOICES"
          regex: "INVOICE*"

我需要循环“过滤器”的子元素。我正在使用以下循环：

loop: "{{ companies | subelements('filters', skip_missing=True) }}"

问题是我需要在模板中填写两个字段：ma​​tch 和 else。 ma​​tch 字段应该是循环的当前项。第二个字段应该是下一项。

例如，如果我有这个子元素结构： 子元素： sub1：值 sub2：值 sub3: 值

然后我在这些子元素上使用循环，我的模板中的两个字段应该如下所示：

match_send=sub1
else_send=sub2

然后是下一项

match_send=sub2
else_send=sub3

我该怎么做？

谢谢。

Answer 1

问：“match and else。匹配字段应该是循环的当前项。第二个字段应该是下一项。”

答：Extended loop variables 服务于这个目的。例如

- hosts: localhost
  vars:
    companies:
      - name: 'Amazon'
        filters:
          - 'filter-A1'
          - 'filter-A2'
          - 'filter-A3'
      - name: 'Facebook'
        filters:
          - 'filter-F1'
          - 'filter-F2'
          - 'filter-F3'
      - name: 'Google'
        filters:
          - 'filter-G1'
          - 'filter-G2'
          - 'filter-G3'

  tasks:

    - debug:
        msg:
          - "match: {{ item.0.name }} -
                    {{ item.1 }}"
          - "else: {{ ansible_loop.nextitem.0.name|default('last item') }} -
                   {{ ansible_loop.nextitem.1|default('last subitem') }}"
      loop: "{{ companies|subelements('filters', skip_missing=True) }}"
      loop_control:
        extended: true

给予

    "msg": [
        "match: Amazon - filter-A1", 
        "else: Amazon - filter-A2"
    ]
--
    "msg": [
        "match: Amazon - filter-A2", 
        "else: Amazon - filter-A3"
    ]
--
    "msg": [
        "match: Amazon - filter-A3", 
        "else: Facebook - filter-F1"
    ]
--
    "msg": [
        "match: Facebook - filter-F1", 
        "else: Facebook - filter-F2"
    ]
--
    "msg": [
        "match: Facebook - filter-F2", 
        "else: Facebook - filter-F3"
    ]
--
    "msg": [
        "match: Facebook - filter-F3", 
        "else: Google - filter-G1"
    ]
--
    "msg": [
        "match: Google - filter-G1", 
        "else: Google - filter-G2"
    ]
--
    "msg": [
        "match: Google - filter-G2", 
        "else: Google - filter-G3"
    ]
--
    "msg": [
        "match: Google - filter-G3", 
        "else: last item - last subitem"
    ]

问：“我希望它表现得像这样：”

 "msg": [ "match: Facebook - filter-F2",
          "else: Facebook - filter-F3" ]
 "msg": [ "match: Facebook - filter-F3",
          "else: " ]

“例如，当到达 Facebook 的最后一个子项时，next_item 的值应该为空。”

答：试试这个

    - debug:
        msg: "{{ msg.split('\n') }}"
      vars:
        msg: |
          - match: {{ item.0.name }} -  {{ item.1 }}
          {% if item.0.name == ansible_loop.nextitem.0.name|default('last item') %}
          - else: {{ ansible_loop.nextitem.0.name }} -  {{ ansible_loop.nextitem.1 }}
          {% else %}
          - else: ''
          {% endif %}
      loop: "{{ companies|subelements('filters', skip_missing=True) }}"
      loop_control:
        label: "{{ item.0.name }}"
        extended: true

最后，如果你想用这个列表创建一个变量，试试

    - set_fact:
        companies1: "{{ companies1|default([]) + [company|from_yaml] }}"
      vars:
        company: |
          [{match: '{{ item.0.name }} - {{ item.1 }}'},
          {%- if item.0.name == ansible_loop.nextitem.0.name|default('last item') %}
          {else: '{{ ansible_loop.nextitem.0.name }} -  {{ ansible_loop.nextitem.1 }}'}]
          {%- else %}
          {else: ''}]
          {% endif %}
      loop: "{{ companies|subelements('filters', skip_missing=True) }}"
      loop_control:
        label: "{{ item.0.name }}"
        extended: true
    - debug:
        msg: "{{ msg.split('\n') }}"
      vars:
        msg: "{{ companies1|to_yaml }}"

给

    "msg": [
        "- - {match: Amazon - filter-A1}", 
        "  - {else: Amazon -  filter-A2}", 
        "- - {match: Amazon - filter-A2}", 
        "  - {else: Amazon -  filter-A3}", 
        "- - {match: Amazon - filter-A3}", 
        "  - {else: ''}", 
        "- - {match: Facebook - filter-F1}", 
        "  - {else: Facebook -  filter-F2}", 
        "- - {match: Facebook - filter-F2}", 
        "  - {else: Facebook -  filter-F3}", 
        "- - {match: Facebook - filter-F3}", 
        "  - {else: ''}", 
        "- - {match: Google - filter-G1}", 
        "  - {else: Google -  filter-G2}", 
        "- - {match: Google - filter-G2}", 
        "  - {else: Google -  filter-G3}", 
        "- - {match: Google - filter-G3}", 
        "  - {else: ''}", 
        ""
    ]

Answer 2

尽管我的 cmets 我认为我找到了解决方案。 您也许可以使用 with_together。

我想出了一个可行的例子：

---
- hosts: localhost
  vars:
  - list1:
    - a
    - b
    - c
  tasks:
  - name: with_together
    debug:
      msg: "{{ item.0 }} - {{ item.1 }}"
    with_together:
      - "{{ list1 }}"
      - "{{ list1[1:] }}"

给出：

TASK [with_together] ************************************************************************************************************************************************
ok: [localhost] => (item=[u'a', u'b']) => {
    "msg": "a - b"
}
ok: [localhost] => (item=[u'b', u'c']) => {
    "msg": "b - c"
}
ok: [localhost] => (item=[u'c', None]) => {
    "msg": "c - "
}

我相信您可以根据您的用例对其进行调整。