使用jinja的set_fact列表

Question

我在努力学习忍者和安理。这是在RHEL 7.9，

ansible 2.9.27
  ansible python module location = /usr/lib/python2.7/site-packages/ansible
  executable location = /bin/ansible
  python version = 2.7.5 (default, May 27 2022, 11:27:32) [GCC 4.8.5 20150623 (Red Hat 4.8.5-44)]

我做这个练习的唯一原因是学习。但我很困惑。为什么这不从found_route_list (也就是列表)生成一个列表？

    - name: Populate appended route list
      set_fact:
        found_added_routes: |- 
          {%- set blah = [] %}
            {%- for line in found_route_list %}
              {%- set _ = blah.append(line) %}
            {%- endfor %} 
          {{ blah }}

我的剧本从收集服务器上的路径开始：

- name: Get route info
  shell: /usr/sbin/ip route show | sed -e 's/ proto.*//' 
  register: cmdtmp
  changed_when:
    - cmdtmp.stdout | length == 0

- name: Get route list
  set_fact:
    found_route_list: "{{ cmdtmp.stdout.split('\n') }}"

只产生几行输出，如下所示：

default via 10.13.99.1 dev bond0.99
10.13.101.0/23 dev p1p1.101
128.1.66.227 via 10.13.101.1 dev p1p1.101

我使用set_fact到found_added_routes对其执行上述附加操作。然后我调试：

- name: Debug found_route_list
  debug:
    msg: "Found route list: {{ item }}"
  loop: "{{ found_route_list }}"

- name: Debug found_added_routes
  debug:
    msg: "Found: {{ item }}"
  loop: "{{ found_added_routes }}"

这是我的输出：

TASK [networks : Debug found_route_list] **********************************************************************************************************************
ok: [server01.example.com] => (item=default via 10.13.99.1 dev bond0.99) => {
    "msg": "Found route list: default via 10.13.99.1 dev bond0.99"
}
ok: [server01.example.com] => (item=10.13.101.0/24 dev p1p1.101) => {
    "msg": "Found route list: 10.13.101.0/24 dev p1p1.101"
}
ok: [server01.example.com] => (item=128.1.66.227 via 10.13.101.1 dev p1p1.101) => {
    "msg": "Found route list: 128.1.66.227 via 10.13.101.1 dev p1p1.101"
}

TASK [networks : Debug found_added_routes] ********************************************************************************************************************
fatal: [server01.example.com]: FAILED! => {"msg": "Invalid data passed to 'loop', it requires a list, got this instead:  [u'default via 10.13.99.1 dev bond0.99', u'10.13.101.0/24 dev p1p1.101', u'128.1.66.227 via 10.13.101.1 dev p1p1.101']. Hint: If you passed a list/dict of just one element, try adding wantlist=True to your lookup invocation or use q/query instead of lookup."}

我试图像这样创建我的列表，但是我得到了相同的输出：

- name: Populate appended route list
  set_fact:
    found_added_routes: "{%- set blah = [] %}
        {%- for line in found_route_list %}
          {%- set _ = blah.append(line) %}
        {%- endfor %} 
      {{ blah }}"

此外，我在set_fact中看到了语法，您可以执行类似于：set_fact: |-之类的操作，但在我的一生中，我找不到任何文档或引用。你能告诉我什么能解释吗？

谢谢。

Answer 1

模板的结果总是字符串。引文

Jinja可以生成任何基于文本的格式。

查看变量found_added_routes的类型

    - debug:
        var: found_added_routes|type_debug

给出

  found_added_routes|type_debug: str

字符串是有效的YAML。使用筛选器from_yaml并将字符串转换为列表。例如,

    - debug:
        var: item
      loop: "{{ found_added_routes|from_yaml }}"

给予(删节)

  item: default via 10.13.99.1 dev bond0.99
  item: 10.13.101.0/24 dev p1p1.101
  item: 128.1.66.227 via 10.13.101.1 dev p1p1.101