如何使用ansible从json读取值

Question

有下面的 Json。如何提取某个值，例如名称，即 VLAN 或值 (12321321412a-10)。尝试过使用

    - name: Read data from Json
  set_fact:
    Value: "{{ lookup('file', 'POST.json') | from_json }}"

- name: Get the value from JSON
  debug:
    msg: "The value is  {{ value.value }}"

我得到以下输出

TASK [Get the value from JSON] ************************

致命：失败！ => {“msg”：“该任务包含一个带有未定义变量的选项。错误是：'值'未定义

示例 Json

{
"fulfilmentOrderItems": [
    {
        "customerDates": {
        },
        "instanceCharacteristics": [
            {
                "name": "VLAN",
                "value": "24",
                "action": "Cancel"
            }
        ],
        "orderLineId": {
            "value": "123456-10",
            "source": "AS"
        }
    }
],
"orderId": {
    "identifier": {
        "value": "1234567-96_11",
        "source": "AS"
    },
    "version": 1
}

}

Answer 1

不可能在某些地方更新变量，但是，您可以使用

update_fact

模块 – 更新当前设置的事实来创建其他数据结构。

一个最小的示例手册

---
- hosts: localhost
  become: false
  gather_facts: false

  tasks:

    - include_vars:
        file: sample.json
        name: readFromFile

    - debug:
        msg: "{{ readFromFile }}"

    - debug:
        msg: "{{ ((readFromFile.fulfilmentOrderItems | first).instanceCharacteristics | first).value }}"

    - name: Update the fact
      ansible.utils.update_fact:
        updates:
          - path: readFromFile.fulfilmentOrderItems[0].instanceCharacteristics[0].value
            value: '0'
      register: updated

    - debug:
        msg: "{{ updated.readFromFile }}"

将产生

的输出

TASK [include_vars] ***********
ok: [localhost]

TASK [debug] *****************
ok: [localhost] =>
  msg:
    fulfilmentOrderItems:
    - customerDates: {}
      instanceCharacteristics:
      - action: Cancel
        name: VLAN
        value: '24'
      orderLineId:
        source: AS
        value: 123456-10
    orderId:
      identifier:
        source: AS
        value: 1234567-96_11
      version: 1

TASK [debug] *****************
ok: [localhost] =>
  msg: '24'

TASK [Update the fact] *******
changed: [localhost]

TASK [debug] *****************
ok: [localhost] =>
  msg:
    fulfilmentOrderItems:
    - customerDates: {}
      instanceCharacteristics:
      - action: Cancel
        name: VLAN
        value: '0'
      orderLineId:
        source: AS
        value: 123456-10
    orderId:
      identifier:
        source: AS
        value: 1234567-96_11
      version: 1

进一步阅读

• 如何使用 Ansible 读取 JSON 文件？
• Ansible - 更改注册变量
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