按空格拆分字符串,然后在 ansible/jinja2 中再次加入

splitting string by whitespace and then joining it again in ansible/jinja2

我正在尝试 "cleanup" Ansible (ansible-2.1.1.0-1.fc24.noarch) 剧本中变量中的空格,但我会先 split () 它,然后再次 join(' ')。由于某种原因,这种方法给我以下错误:-/

---
- hosts: all
  remote_user: root
  vars:
    mytext: |
      hello
      there how   are
      you?
  tasks:
    - debug:
        msg: "{{ mytext }}"
    - debug:
        msg: "{{ mytext.split() }}"
    - debug:
        msg: "{{ mytext.split().join(' ') }}"
...

给我:

TASK [debug] *******************************************************************
ok: [192.168.122.193] => {
    "msg": "hello\nthere how   are\nyou?\n"
}

TASK [debug] *******************************************************************
ok: [192.168.122.193] => {
    "msg": [
        "hello", 
        "there", 
        "how", 
        "are", 
        "you?"
    ]
}

TASK [debug] *******************************************************************
fatal: [192.168.122.193]: FAILED! => {"failed": true, "msg": "the field 'args' has an invalid value, which appears to include a variable that is undefined. The error was: 'list object' has no attribute 'join'\n\nThe error appears to have been in '.../tests.yaml': line 15, column 7, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n        msg: \"{{ mytext.split() }}\"\n    - debug:\n      ^ here\n"}

知道我做错了什么吗?它说 字段 'args' 有一个无效值,它似乎包含一个未定义的变量。错误是:'list object' 没有属性 'join',但根据 useful filters 文档,它应该有效。

您应该使用管道来应用过滤器:

- debug:
    msg: "{{ mytext.split() | join(' ') }}"

在这个例子中 split() 是字符串对象的 Python 方法。所以有点黑客。
join(' ') 是一个 Jinja2 过滤器,它将列表连接成字符串。

调用 mytext.split().join(' ') 会出错,因为 Python.
中的列表没有 join 方法 在 Python 中有 join 字符串方法,您可以调用 ' '.join(mytext.split()),但这将是一个双重 hack。