时间戳

首页 > 解决方案 > Ansible - json解析 - “未定义变量”

json - Ansible - json解析 - “未定义变量”

问题描述

环境：

给定 API 响应，我试图获取地址，但得到“未定义变量”。这是一个将 API 响应作为 var 的剧本：

---

- name: test
  gather_facts: no
  hosts: localhost
  vars:
    pool_details: {
        "allow": "",
        "cache_control": "no-store, no-cache, must-revalidate",
        "changed": false,
        "connection": "close",
        "content_length": "668",
        "content_security_policy": "default-src 'self'  'unsafe-inline' 'unsafe-eval' data: blob:; img-src 'self' data:  http://127.4.1.1 http://127.4.2.1",
        "content_type": "application/json; charset=UTF-8",
        "cookies": {},
        "cookies_string": "",
        "date": "Tue, 24 Aug 2021 16:34:47 GMT",
        "elapsed": 0,
        "expires": "-1",
        "failed": false,
        "json": {
            "items": [
                {
                    "address": "10.200.136.22",
                    "connectionLimit": 0,
                    "dynamicRatio": 1,
                    "ephemeral": "false",
                    "fqdn": {
                        "autopopulate": "disabled"
                    },
                    "fullPath": "/Common/sensor01:443",
                    "generation": 103,
                    "inheritProfile": "enabled",
                    "kind": "tm:ltm:pool:members:membersstate",
                    "logging": "disabled",
                    "monitor": "default",
                    "name": "sensor01:443",
                    "partition": "Common",
                    "priorityGroup": 0,
                    "rateLimit": "disabled",
                    "ratio": 1,
                    "selfLink": "https://localhost/mgmt/tm/ltm/pool/~Common~sensor01/members/~Common~sensor01:443?ver=16.1.0",
                    "session": "monitor-enabled",
                    "state": "up"
                }
            ],
            "kind": "tm:ltm:pool:members:memberscollectionstate",
            "selfLink": "https://localhost/mgmt/tm/ltm/pool/~Common~sensor01/members?ver=16.1.0"
        },
        "msg": "OK (668 bytes)",
        "pragma": "no-cache",
        "redirected": false,
        "server": "Jetty(9.2.22.v20170606)",
        "status": 200,
        "strict_transport_security": "max-age=16070400; includeSubDomains",
        "x_content_type_options": "nosniff",
        "x_frame_options": "SAMEORIGIN",
        "x_xss_protection": "1; mode=block"
    }
  tasks:
    - debug:
        var: pool_details

    - debug:
        var: pool_details.json.items[0].address

启用详细程度的完整错误是：

pool_details.json.items[0].address: 'VARIABLE IS NOT DEFINED!: builtin_function_or_method object has no element 0'

我获取地址的第二次调试不起作用（“未定义”），我不知道为什么。如果我采用相同的 json，并将其通过管道传输到 jq，它就可以正常工作：

pbpaste | jq '.json.items[0].address'
"10.200.136.22"

标签： jsonansible

解决方案

如果列表中有更多项目，您可能想要使用json_query，例如

    - set_fact:
        list_address: "{{ pool_details.json['items']|
                          json_query('[].address') }}"

给

  list_address:
  - 10.200.136.22

如果您不想或不能安装 JmesPath，下一个选项将是map 属性，例如下面的代码给出相同的结果

    - set_fact:
        list_address: "{{ pool_details.json['items']|
                          map(attribute='address')|
                          list }}"

推荐阅读