string - Ansible:意外的模板类型错误:预期的字符串或缓冲区

Question

我有一个包含以下内容的寄存器:

ok: [hostname] => {
    "changed": false,
    "msg": {
        "changed": true,
        "cmd": "cd /tmp\n ./status.sh dev",
        "delta": "0:00:00.023660",
        "end": "2018-11-28 17:46:05.838934",
        "rc": 0,
        "start": "2018-11-28 17:46:05.815274",
        "stderr": "",
        "stderr_lines": [],
        "stdout": "application is not running. no pid file found",
        "stdout_lines": [
            "application is not running. no pid file found"
         ]
    }
}

当我在寄存器的标准输出中看到子字符串“not”时，我想触发另一个任务:

  - name: Starting Application As Requested
    shell: /tmp/start.sh
    when: operation_status.stdout | search('not')

但是，我在触发的任务中看到此错误

fatal: [host]: FAILED! => {
"failed": true,
"msg": "The conditional check 'operation_status.stdout | search('not')' failed. The error was: Unexpected templating type error occurred on ({% if operation_status.stdout | search('not') %} True {% else %} False {% endif %}): expected string or buffer\n\nThe error appears to have been in '/path/to/ansible_playbook.yml': line 46, column 5, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n\n  - name: Starting Application As Requested\n    ^ here\n"

当添加when条件时，我只会看到此错误。没有它，我的剧本就成功了。我在这里做错了什么？

版本详细信息:

ansible 2.3.0.0
python version = 2.6.6 (r266:84292, Aug  9 2016, 06:11:56) [GCC 4.4.7 20120313 (Red Hat 4.4.7-17)]

Answer 1

当变量(在您的情况下为operation_status.stdout)未定义时，会发生此错误。服务运行时，status.sh脚本可能不会写入stdout。

您是否可以将调试任务放到任务前面，并用“when”打印此变量的值？

- name: Debug print value of operation_status.stdout
  debug:var=operation_status.stdout

您也可以尝试将when条件修改为:

  - name: Starting Application As Requested
    shell: /tmp/start.sh
    when: "'not' in operation_status.stdout"