如何提取嵌套列表内字典的hostname值？解决TypeError问题

尝试从嵌套了列表与字典的JSON响应中提取hostname值时，触发TypeError: list indices must be integers or slices, not str错误，目标是生成以propertyName为键、对应hostname列表为值的字典结构。

返回的JSON示例 #

{
    "accountId": "act_1234",
    "contractId": "ctr_1234",
    "groupId": "grp_1234",
    "propertyId": "prp_1234",
    "propertyName": "www.property.com",
    "propertyVersion": 1,
    "etag": "jbcas6764023nklf78354",
    "rules": {
        "name": "default",
        "children": [{
            "name": "Route",
            "children": [],
            "behaviors": [{
                "name": "origin",
                "options": {
                    "originType": "CUSTOMER",
                    "hostname": "www.origin.com",
                    "forwardHostHeader": "REQUEST_HOST_HEADER"
                }
            }]
        }]
    }
}

现有报错代码 #

#get hostnames of each property
for (j, k) in itertools.zip_longest(propid, prodversion):
    propertyId = str(j)
    propertyVersion = str(k)    
    path= '/sample/v1/properties/{}/versions/{}/rules'.format(propertyId, propertyVersion)
    headers = {
        "Accept": "application/json",
        "PAPI-Use-Prefixes": "true"
    }
    querystring = {
        "contractId": "ctr_1234",
        "groupId": str(i),
        "validateRules": "true",
        "validateMode": "full"
    }
    result = session.get(urljoin(baseurl, path), headers=headers, params=querystring, verify=False)
    hostnames = result.json()
    hostnameslist = [host['hostname'] for host in hostnames['rules']['children']['behaviors']['options']]
    print(hostnameslist)

错误原因 #

• hostnames['rules']['children']是列表类型，无法直接通过字符串索引访问，必须使用整数下标或遍历列表元素
• 每个children元素中的behaviors同样是列表，需要遍历或下标访问其中的字典项
• 原代码直接对列表使用字符串索引，导致类型不匹配错误

修复后的代码 #

import itertools
from urllib.parse import urljoin

# 初始化结果字典
properties_hostnames = {'properties': {}}

#get hostnames of each property
for (j, k) in itertools.zip_longest(propid, prodversion):
    propertyId = str(j)
    propertyVersion = str(k)    
    path= '/sample/v1/properties/{}/versions/{}/rules'.format(propertyId, propertyVersion)
    headers = {
        "Accept": "application/json",
        "PAPI-Use-Prefixes": "true"
    }
    querystring = {
        "contractId": "ctr_1234",
        "groupId": str(i),
        "validateRules": "true",
        "validateMode": "full"
    }
    result = session.get(urljoin(baseurl, path), headers=headers, params=querystring, verify=False)
    property_data = result.json()
    
    # 获取当前property的名称
    prop_name = property_data['propertyName']
    current_hostnames = []
    
    # 遍历rules下的children列表
    for child in property_data['rules']['children']:
        # 遍历每个child下的behaviors列表
        for behavior in child['behaviors']:
            # 提取hostname并加入列表
            if 'options' in behavior and 'hostname' in behavior['options']:
                current_hostnames.append(behavior['options']['hostname'])
    
    # 将结果存入目标字典
    properties_hostnames['properties'][prop_name] = current_hostnames

print(properties_hostnames)

期望输出结构 #

{
    'properties': {
        'www.property1.com': ['www.origin1.com', 'www.origin2.com'],
        'www.property2.com': ['www.origin1.com', 'www.origin2.com']
    }
}

内容的提问来源于stack exchange，提问作者francorocks