解析 JSON - TypeError：字符串索引必须是整数

Question

我需要检索 GoDaddy 证书名称和到期日期。 我正在尝试这样的代码：

def get_cert():
    customerId = "UUID"
    cert_url = "https://api.godaddy.com//v2/customers/%s/certificates" %(customerId)

    cert_response = requests.get(cert_url, headers=headers)
    cert_dict = json.loads(cert_response.text)
    for cert in cert_dict:
        cert_name = (cert['commonName'])
        print(cert_name)

并得到如下错误：

    cert_name = (cert['commonName'])
TypeError: string indices must be integers

Output 来自 API 调用，无需解析：

        {
            "certificateId": "ID", 
            "commonName": "*.domain.co.uk", 
            "completedAt": "2021-01-12T14:26:36Z", 
            "createdAt": "2020-04-02T14:25:06Z", 
            "period": 1, 
            "serialNumber": "NUMBER", 
            "status": "CURRENT", 
            "type": "DV_WILDCARD_SSL", 
            "validEndAt": "2022-05-04T14:26:32Z", 
            "validStartAt": "2021-04-02T14:26:32Z"
        }

I have the same code for GoDaddy domains API and it works properly (logic is the same, difference only in API URL and keys) so I can`t understand why its forbidden to cut json output by "commonName" and "validEndAt" in this案子。

Answer 1

确保您收到的是您假设的数据类型。 如果解码产生包含dict对象的list实例，则您拥有的代码是合适的。 您收到的错误消息似乎是一个dict 。

当您遍历dict时，您将收到它的所有键。 如果您确切知道所需的密钥，则无需对其进行迭代。

def get_cert():
    customerId = "UUID"
    cert_url = "https://api.godaddy.com//v2/customers/%s/certificates" %(customerId)

    cert_response = requests.get(cert_url, headers=headers)
    cert_dict = json.loads(cert_response.text)
    print(cert_dict['commonName'])

如果密钥不存在，这将引发错误。 另一种尝试在没有任何异常的情况下检索它的方法是：

common_name = cert_dict.get('commonName')

如果密钥不存在， common_name将为None