在 Ansible 中读取时如何处理 JSON 数组中缺少的键

Question

下面是我的JSON文件：

[
{
"?xml": {
"attributes": {
"encoding": "UTF-8",
"version": "1.0"
}
}
},
{
"domain": [
{
"name": "mydom"
},
{
"domain-version": "12.2.1.3.0"
},
{
"server": [
{
"name": "AdminServer"
},
{
"ssl": {
"name": "AdminServer"
}
},
{
"listen-port": "12400"
},
{
"listen-address": "mydom.host1.bank.com"
}
]
},
{
"server": [
{
"name": "myserv1"
},
{
"ssl": [
{
"name": "myserv1"
},
{
"login-timeout-millis": "25000"
}
]
},
{
"log": [
{
"name": "myserv1"
},
{
"file-name": "/web/bea_logs/domains/mydom/myserv1/myserv1.log"
}
]
}
]
},
{
"server": [
{
"name": "myserv2"
},
{
"ssl": {
"name": "myserv2"
}
},
{
"reverse-dns-allowed": "false"
},
{
"log": [
{
"name": "myserv2"
},
{
"file-name": "/web/bea_logs/domains/mydom/myserv2/myserv2.log"
}
]
}
]
}
]
}
]

我需要使用 ansible 代码获取日志列表的name和file-name，如下所示。

myserv1_log: "/web/bea_logs/domains/mydom/myserv1/myserv1.log"
myserv2_log: "/web/bea_logs/domains/mydom/myserv2/myserv2.log"

我面临两个挑战。

1. server可能并不总是domain数组的第 3 个键。
2. log数组可能并不总是所有server数组的键，因此不应打印。例如。server名称 AdminServer 没有任何log列表，而 myserv1 和 myserv2 有。

我需要一个 ansible 代码来打印动态变化的 json 所需的代码。

注意：server将始终是domain数组中的键

我在这里发布参考我的类似查询：无法理想地解析 ansible 中的 json 文件

恳请建议。

Answer 1

您只需测试两个键是否存在：

- hosts: localhost
gather_facts: no
vars:
json: "{{ lookup('file', './file.json') | from_json }}"
tasks:
- name: display
debug:
msg: "name: {{ servername }} --> filename: {{ filename }}"
loop: "{{ json[1].domain }}"
vars:
servername: "{{ item.server.0.name }}_log"
filename: "{{ item['server'][2]['log'][1]['file-name'] }}"
when: item.server is defined and item.server.2.log is defined

结果：

TASK [display] 
skipping: [localhost] => (item={'name': 'USWL1212MRSHM01'}) 
skipping: [localhost] => (item={'domain-version': '12.2.1.3.0'}) 
skipping: [localhost] => (item={'server': [{'name': 'AdminServer'}, {'ssl': {'name': 'AdminServer'}}, {'listen-port': '12400'}, {'listen-address': 'myhost1'}]}) 
ok: [localhost] => (item={'server': [{'name': 'myserv1'}, {'ssl': {'name': 'myserv1'}}, {'log': [{'name': 'myserv1'}, {'file-name': '/web/bea_logs/domains/mydom/myserv1/myserv1.log'}]}]}) => {
"msg": "name: myserv1_log --> filename: /web/bea_logs/domains/mydom/myserv1/myserv1.log"
}
ok: [localhost] => (item={'server': [{'name': 'myserv2'}, {'ssl': {'name': 'myserv2'}}, {'log': [{'name': 'myserv2'}, {'file-name': '/web/bea_logs/domains/mydom/myserv2/myserv2.log'}]}]}) => {
"msg": "name: myserv2_log --> filename: /web/bea_logs/domains/mydom/myserv2/myserv2.log"
}

如您所见，当条件不为真时，将跳过该操作...

您可以通过仅测试键log来简化，因为在您的情况下，键log始终链接到键server

when: item.server.2.log is defined