如何使用 Ansible 检查给定目录是否为空？答案

【问题标题】：How do I check whether a given directory is empty with Ansible?如何使用 Ansible 检查给定目录是否为空？
【发布时间】：2019-06-06 13:41:06
【问题描述】：

我正在尝试实现一个角色，在继续执行剧本的其余部分之前检查给定目录是否为空。

我已经尝试过这段代码，但我遇到了一个错误，我不确定正确的实现。

- name: Check if d folder is empty before proceeding
  find:
   paths: c/d/
   patterns: "*.*"
   register: filesFound

- fail:
     msg: The d folder is not empty. 
  when: filesFound.matched > 0

- debug:
    msg: "The d folder is empty. Proceeding."

这是我得到的错误：

fatal FAILED! =>
{"changed": false,
"module_stderr": "Exception calling \"Create\" with \"1\" argument(s):
\"At line:4 char:21
def _ansiballz_main():
An expression was expected after '('.
At line:12 char:27
except (AttributeError, OSError):
Missing argument in parameter list.
At line:14 char:7
if scriptdir is not None:
Missing '(' after 'if' in if statement.
At line:21 char:7
if sys.version_info < (3,):
Missing '(' after 'if' in if statement.
At line:21 char:30
if sys.version_info < (3,):
Missing expression after ','.
At line:21 char:25
if sys.version_info < (3,):
The '<' operator is reserved for future use.
At line:23 char:32
MOD_DESC = ('.py', 'U', imp.PY_SOURCE)
Missing expression after ','.
At line:23 char:33
MOD_DESC = ('.py', 'U', imp.PY_SOURCE)                                 Unexpected token 'imp.PY_SOURCE' in expression or statement.
At line:23 char:32
MOD_DESC = ('.py', 'U', imp.PY_SOURCE)
Missing closing ')' in expression.
At line:23 char:46
MOD_DESC = ('.py', 'U', imp.PY_SOURCE)
Unexpected token ')' in expression or statement.
Not all parse errors were reported.  Correct the reported errors and try again.\"
At line:6 char:1
$exec_wrapper = [ScriptBlock]::Create($split_parts[0])
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
CategoryInfo          : NotSpecified: (:) [], MethodInvocationException\r\n    + FullyQualifiedErrorId : ParseException\r\n \r\nThe expression after '&' in a pipeline element produced an object that was not valid. It must result in a command
name, a script block, or a CommandInfo object.
At line:7 char:2
&$exec_wrapper
~~~~~~~~~~~~~\
+ CategoryInfo          : InvalidOperation: (:) [], RuntimeException
    + FullyQualifiedErrorId : BadExpression
", "module_stdout": "", "msg": "MODULE FAILURE
See stdout/stderr for the exact error", "rc": 1}

【问题讨论】：

在您的代码中存在缩进错误。寄存器应与查找处于同一级别。此外，您发布的错误似乎并不完整
@HermanTheGermanHesse 谢谢，我已经用完整的错误更新了错误。我已经尝试了你的两个建议，但仍然遇到同样的错误
您是否有机会尝试在 Windows 上运行它？

标签： ansible yaml

【解决方案1】：

你是在正确的方式，但正如@HermanTheGermanHesse 提到的，有一个识别错误，试试这个：

- name: Check if d folder is empty before proceeding
  find:
    paths: 'c/d/'
  register: filesFound

- fail:
     msg: 'The d folder is not empty.'
  when: filesFound.matched > 0

- debug:
    msg: 'The d folder is empty. Proceeding.'

【讨论】：

【解决方案2】：

您可以使用shell module。

- name: Register contents of /a/b/c
  shell: ls -la
  args:
    chdir: /a/b/c
  register: contents

- name: do stuff when not empty
  debug:
    msg: "There are elements inside!"
  when: contents["stdout_lines"] | length > 2

【讨论】：

【解决方案3】：

受Jeremy Canfield 启发的解决方案，它检查目录是否包含文件：

- name: Check if d folder is empty before proceeding
  stat:
    path: c/d/*
  register: filesFound

- fail:
     msg: The d folder is not empty. 
  when: filesFound.stat.exists == true

- debug:
    msg: The d folder is empty. Proceeding.
  when: filesFound.stat.exists == false

【讨论】：