条件超过循环时在 ansible 中搜索字符串

Question

团队，我想在sda设备上循环，只排除loop设备，所以我试图比较字符串的一部分，如果它存在于来自 ansible_devices 项目变量的键中并且卡在语法错误中。

我只想在WHEN条件时打印味精。 基本上，当密钥中有 ZE83AED3DDF4667DEC0DAAAACB2BB3BE0BZ loop时，我只想打印消息。

我有以下示例 output 并且我能够检索它，但现在我想将它与一些字符串进行比较但失败，如任务中标记的#fails

值.yml

loop_device: "loop"

任务.yaml

  debug:
    msg: "{{ ansible_hostname }} {{ item }} {{ ansible_devices[item]['partitions'] }}"
  when:
    - "not ansible_devices[item] is search('loop')" #fails
    - ansible_devices[item]['partitions'] is mapping #works
    - ansible_devices[item]['partitions'] | length == 0 #works
  with_items: "{{ ansible_devices }}"

output 错误：

 TASK [local_volume_mount : Print device partitions that are defined using mapping] ***
17:14:23  Tuesday 27 April 2021  
17:14:23  fatal: [node1]: FAILED! => {"msg": "The conditional check 'not ansible_devices[item] is search('loop')' failed. The error was: Unexpected templating type error occurred on ({% if not ansible_devices[item] is search('loop') %} True {% else %} False {% endif %}): expected string or bytes-like object\n\nThe error appears to be in '/ansible-managed/jenkins-slave/slave0/workspace/run_ansible_playbook/k8s/baremetal/roles/local_volume_mount/tasks/main.yml': line 24, column 3, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n\n- name: Print device partitions that are defined using mapping\n  ^ here\n"}

示例ansible_Devices如下

ok: [node1] => {
       "ansible_devices": {
           "loop0": {
               "holders": [],
               "host": "",
               "links": {
                   "ids": [],
                   "labels": [],
                   "masters": [],
                   "uuids": []
               },
               "model": null,
               "partitions": {},
               "removable": "0",
               "rotational": "1",
               "sas_address": null,
               "sas_device_handle": null,
               "scheduler_mode": "none",
               "sectors": "0",
               "sectorsize": "512",
               "size": "0.00 Bytes",
               "support_discard": "0",
               "vendor": null,
               "virtual": 1
           },
          "sda2": {
               "holders": [],
               "host": "",
               "links": {
                   "ids": [],
                   "labels": [],
                   "masters": [],
                   "uuids": []
               },
               "model": null,
               "partitions": {},
               "removable": "0",
               "rotational": "1",
               "sas_address": null,
               "sas_device_handle": null,
               "scheduler_mode": "none",
               "sectors": "0",
               "sectorsize": "512",
               "size": "0.00 Bytes",
               "support_discard": "0",
               "vendor": null,
               "virtual": 1
           },

output 仍在打印循环装置

  ok: [node1] => (item=loop0) => {
      "msg": "node1 loop0 {}"
  }
  ok: [node1] => (item=loop0) => {
      "msg": "node1 sda2 {}"
  }

我什至尝试了以下组合

    - '"loop" not in ansible_devices[item]'
    - ansible_devices[item] is not match("loop")
    - ansible_devices[item] is not search("loop")

尝试了下面的答案 1

- debug: after entering loop efficient
    msg: "{{ ansible_hostname }} {{ item.key }} {{ item.value.partitions }}"
  when:
    - item.key is not search('loop')
    - item.value.partitions is mapping
    - item.value.partitions | length == 0
  loop: "{{ ansible_devices | dict2items }}"
  with_dict: "{{ ansible_devices }}"

带有 dict2items 的 Answer1 的错误 output

 ERROR! Syntax Error while loading YAML.
    mapping values are not allowed here
  
  The error appears to be in '/ansible-managed/jenkins-slave/slave0/workspace/run_ansible_playbook/k8s/baremetal/roles/local_volume_mount/tasks/main.yml': line 25, column 8, but may
  be elsewhere in the file depending on the exact syntax problem.
  
  The offending line appears to be:
  
  - debug: after entering loop efficient
      msg: "{{ ansible_hostname }} {{ item.key }} {{ item.value.partitions }}"
         ^ here
  We could be wrong, but this one looks like it might be an issue with
  missing quotes. Always quote template expression brackets when they
  start a value. For instance:
  
      with_items:
        - {{ foo }}
  
  Should be written as:
  
      with_items:
        - "{{ foo }}"

Answer 1

快速修复 => item is not search('loop')

由于您在 dict 上使用with_items ，因此循环中仅返回其键列表。 因此item是您要搜索的键。

同时，有一种更有效的方法来遍历你的字典，它将返回一个包含键和值的元素。

• 历史语法： with_dict: "{{ ansible_devices }}"
• 新语法： loop: "{{ ansible_devices | dict2items }}"

请参阅： https://docs.ansible.com/ansible/latest/user_guide/playbooks_loops.html

在您的情况下，这将给出：

- debug:
    msg: "{{ ansible_hostname }} {{ item.key }} {{ item.value.partitions }}"
  when:
    - item.key is not search('loop')
    - item.value.partitions is mapping
    - item.value.partitions | length == 0
  loop: "{{ ansible_devices | dict2items }}"

---

实际上，我们可以进一步 go 并在开始循环之前从 dict 中过滤掉大部分元素。 我们仍然需要检查 when 子句中的长度，因为这在过滤期间不容易计算

- debug:
    msg: "{{ ansible_hostname }} {{ item.key }} {{ item.value.partitions }}"
  when: item.value.partitions | length == 0
  loop: >-
    {{
      ansible_devices
      | dict2items
      | rejectattr('key', 'search', 'loop')
      | selectattr('value.partition', 'mapping')
      | list
    }}

Answer 2

经过几次组合后才知道。

- '"loop" not in item'或

在 values.yml 中定义

loop_device_substring: "loop"

任务.yaml

- '"{{ loop_device_substring }}" not in item'

以下是完整的任务，其中一个选项已注释。

- name: "Print device partitions that are Null and not a loop device"
  debug:
    msg: "{{ ansible_hostname }} {{ item }} {{ ansible_devices[item]['partitions'] }}"    
  when:
    - ansible_devices[item]['partitions'] | length == 0
    - ansible_devices[item]['partitions'] is mapping
    - '"loop" not in item'
    #- '"{{ loop_device_substring }}" not in item'
  with_items: "{{ ansible_devices }}"

output

  skipping: [node1] => (item=loop0) 
 ok: [node1] => (item=sda2) => {
      "msg": "node1 sda2 {}"
  }