问题

使用情况 - 我有一个名为os_family的粒度值，这个家族通过后端的自动化脚本进行更新，我想检测这个更改并在更改时触发自定义的反应器状态。

问题 - 我已经添加了反应器配置并编写了一个状态，但事件没有生成，似乎触发器不起作用。

我附上了我的代码文件如下：

/etc/salt/master/reactor.conf

reactor:
  - 'os_family_changed':
    - /srv/salt/reactor/os_family_changed.sls

/srv/salt/reactor/os_family_changed.sls:

{% set old_os_family = grains['os_family'] %}
{% if grains['os_family'] != old_os_family %}
my_grain_changed:
  module.run:
    - name: state.apply
    - tgt: {{ data['id'] }}
    - arg:
      - test_os_family_changed.sls
{% endif %}

test_os_family_changed.sls:

test:
  cmd.run:
    - name: |
                echo 'hi' >> /tmp/test

注意：我希望将这个用例扩展到将来能够从EC2 AWS元数据中读取粒度值。

我不确定如何实现这一点或者我漏掉了什么，任何帮助都将不胜感激。

reactor:
  - 'os_family_changed':
    - /srv/salt/reactor/os_family_changed.sls

{% set old_os_family = grains['os_family'] %}
{% if grains['os_family'] != old_os_family %}
my_grain_changed:
  module.run:
    - name: state.apply
    - tgt: {{ data['id'] }}
    - arg:
      - test_os_family_changed.sls
{% endif %}

test:
  cmd.run:
    - name: |
        echo 'hi' >> /tmp/test

答案1

得分: 1

{% set old_os_family = grains['os_family'] %}
{% if grains['os_family'] != old_os_family %}

这个检查永远不会为真，因为你将这两个值设置为相等。

在执行检查之后，你需要更新old_os_family并将其存储在某个持久化的位置。

还要注意，grains不太可能改变，因此它们被大量缓存。可能需要多达几天才能看到变化。

<details>
<summary>英文:</summary>

```python
{% set old_os_family = grains[&#39;os_family&#39;] %}
{% if grains[&#39;os_family&#39;] != old_os_family %}

The check can never be true, because you set the two values to be equal.

You need to update old_os_family and store it somewhere persistent after performing the check.

Note also that grains are not expected to change, and thus are heavily cached. You may not see a change for up to days.