Python中如何将嵌套JSON值保存到变量用于API请求

问题场景 #

需要从API GET请求返回的JSON中提取id值，保存为变量后用于后续POST调用，但尝试提取时触发string indices must be integers错误。

当前代码 #

import requests
from requests.auth import HTTPBasicAuth
import json
import sys
import objectpath

auth = HTTPBasicAuth("Username", "PAssword")
departmentname = "IT" #sys.argv[1]
url = "http://url.com".format( departmentname ) 
headers = {
    "Accept": "application/json",
    "Content-Type": "application/json"
}

response = requests.request(
    "GET",
    url,
    headers=headers,
    auth=auth,
)
r = json.dumps(json.loads(response.text), sort_keys=True, indent=4, separators=(",", ": "))
#print(json.dumps(json.loads(response.text), sort_keys=True, indent=4, separators=(",", ": ")))
response.json()

API响应示例 #

{
    "departments": [
        {
            "created_at": "2022-06-01T17:15:32Z",
            "custom_fields": {},
            "description": "IT Service Team",
            "domains": [],
            "head_user_id": 12345,
            "id": 67890,
            "name": "IT",
            "prime_user_id": null,
            "updated_at": "2022-06-07T16:35:25Z"
        }
    ]
}

错误触发操作 #

执行print(response['departments'][0]['id'][0])时，报错：string indices must be integers

问题原因 #

1. response是Response对象而非字典：直接对response用字典索引会操作响应头，而非响应体内容；
2. r是格式化后的JSON字符串：json.dumps()将解析后的JSON转为字符串，字符串只能用整数索引，无法用键名；
3. 多余的[0]：id是单个数值而非列表，不需要额外索引。

修正方案 #

将响应体解析为字典并提取目标值，代码调整如下：

import requests
from requests.auth import HTTPBasicAuth

auth = HTTPBasicAuth("Username", "PAssword")
departmentname = "IT" #sys.argv[1]
url = "http://url.com".format( departmentname ) 
headers = {
    "Accept": "application/json",
    "Content-Type": "application/json"
}

# 发送GET请求并解析响应为字典
response = requests.get(url, headers=headers, auth=auth)
data = response.json()

# 提取部门ID
department_id = data['departments'][0]['id']
print(f"提取的部门ID: {department_id}")

# 后续POST调用示例
post_url = "http://url.com/post-endpoint"
post_payload = {
    "department_id": department_id,
    # 其他POST参数
}
post_response = requests.post(post_url, json=post_payload, headers=headers, auth=auth)

关键说明 #

• 使用response.json()直接将响应体解析为Python字典，无需手动json.loads(response.text)；
• 提取id时，data['departments'][0]定位到第一个部门对象，再通过['id']获取目标值；
• 保存的department_id可直接传入POST请求的payload中使用。

内容的提问来源于stack exchange，提问作者TL_Arwen