Python 可分解条件模板

我想在ansibles jinja模板中有一个简单的if-else条件。对于普通python

cluster_name+'A' if isCondition is True else cluster_name +'B'

如果定义了以下变量，则效果很好：

isSingleNode = True
cluster_name = 'example'

在ansible中，我看到以下错误：

fatal: [localhost]: FAILED! => {"changed": false, "failed": true, "msg": "AnsibleError: template error while templating string: no test named 'True'. String: {\n\n   \"key\" : \"{{ groups[cluster_name+'_mn01' if isSingleNode is True else cluster_name + '_mn02'] }}\"\n}\n"}

下面是一个简单的例子：

文件1：变量

---
isCondition: True

文件2:playbook.yml

---
- hosts: all
  tasks:
    - include_vars: variables
    - debug: msg=" condition is {{ isCondition }} with cluster_name {{ cluster_name }}"

    - name: copy file
      template: src="bare_cluster.bp.j2" dest={{ cluster_name }}_blueprint.json backup=yes

文件4：库存

[examplecluster:children]
examplecluster_mn01

[mn01:children]
examplecluster_mn01

[examplecluster_mn01]
localhost ansible_connection=local

文件_5:bare_cluster.bp.j2

{

   "key" : "{{ groups[cluster_name+'_mn01' if isSingleNode is True else cluster_name + '_mn02'] }}"
}

执行最小示例的命令是

ansible playbook-i inventory playbook.yml-e'cluster\u name=examplecluster'

您尝试过吗

{% if isCondition %} {{ cluster_name }} A {% else %} {{ cluster_name }} B {% endif %}

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@请解释原因。您不能用jinja2表达式编写任意python代码。