使用 ansible 模板化防火墙区域 - xml 操作问题

在 RHEL7.6 上使用 ansible 2.9 我正在尝试配置单个防火墙区域，其中还包括丰富规则的配置。一切正常，除非我尝试在模板中添加丰富规则。在下面的示例中，我尝试添加允许 VRRP 流量的丰富规则。

Ansible 任务：

    - name: Configure firewalld zones
      template:
        src: zone_template.xml.j2
        dest: /etc/firewalld/zones/{{ item.name }}.xml
      with_items: "{{ firewalld_zones }}"
      notify: reload firewalld
      loop_control:
        label: "{{ item.name }}"

该变量firewalld_zones在我的 defaults/main.yml 中定义如下：

firewalld_zones:
  - name: public
    short: "Public"
    description: "Public Zone"
    port:
      - { port: 300, protocol: tcp }
      - { port: 300, protocol: udp }
    rule:
      - protocol:
          - value: "vrrp"
          - action: accept

我的模板片段zone_template.xml.j2：

<?xml version="1.0" encoding="utf-8"?>
<zone{% if item.target is defined %} target="{{ item.target }}"{% endif %}>
  <short>{{ item.short|default(item.name)|upper  }}</short>
{% if item.description is defined %}
  <description>{{ item.description }}</description>
{% endif %}
{% for tag in item %}
{# Settings which can be used several times #}
{% if tag in ['interface','source','service','port','protocol','icmp-block','forward-port','source-port'] %}
{% for subtag in item[tag] %}
  <{{ tag }}{% for name,value in subtag.items() %} {{ name }}="{{ value }}"{% endfor %}/>
{% endfor %}
{# Settings which can be used once #}
{% elif tag in ['icmp-block-inversion','masquerade'] and item[tag] == True %}
  <{{ tag }}/>
{% endif %}
{% endfor %}
{% for rule in item.rule|default([]) %}
  <rule{% if rule.family is defined %} family="{{ rule.family }}"{% endif %}>
{% for tag in rule %}
{% if tag in ['source','destination','service','port','icmp-block','icmp-type','masquerade','forward-port','protocol'] %}
{% for subtag in rule[tag] %}
{% if subtag in ['action'] %}
    <{% for name,value in subtag.items() %}{{ name }}{% endfor %}/>
{% endif %}
    <{{ tag }}{% for name,value in subtag.items() %} {{ name }}="{{ value }}"{% endfor %}/>
{% endfor %}
{% endif %}
  </rule>
{% endfor %}
{% endfor %}
</zone>

有了这个，我得到：

<?xml version="1.0" encoding="utf-8"?>
<zone>
  <short>PUBLIC</short>
  <description>Public Zone</description>
  <port protocol="tcp" port="300"/>
  <port protocol="udp" port="300"/>
  <rule>
    <protocol value="vrrp"/>
    <protocol action="accept"/>
  </rule>
</zone>

我想要得到的是：

<?xml version="1.0" encoding="utf-8"?>
<zone>
  <short>PUBLIC</short>
  <description>Public Zone</description>
  <port protocol="tcp" port="300"/>
  <port protocol="udp" port="300"/>
  <rule>
    <protocol value="vrrp"/>
    <accept/>
  </rule>
</zone>

我需要改变什么（模板和/或变量）来实现这一点？

谢谢！Ĵ