AttributeError: 'NoneType' object has no attribute 'commit'

Question

我正在使用 JetBrains PYCharm 创建一个连接到外部 API 的 Python 脚本来整理天气数据，请原谅我的无知，我知道类似的问题之前有人问过，请多多包涵我这周才第一次接触Python。

它导入'PostcodeToLatLong' - 顾名思义，这是将标准英国邮政编码转换为一对纬度和经度值。

当我尝试运行 PYCharm 中的代码时，我在 PYCharm 中的调试 window 中得到以下 error/output，我可以看到它与数据库 Connect/Disconnect 功能相关，但不明白为什么我会收到此消息 - 有什么想法吗？：

Exception ignored in: <bound method AA_ForecastIOWeather.__del__ of <__main__.AA_ForecastIOWeather object at 0x01CFB250>>
Traceback (most recent call last):
File "C:/www-service/forecast-io.py", line 18, in __del__
File "C:/www-service/forecast-io.py", line 24, in disconnect_database
AttributeError: 'NoneType' object has no attribute 'commit'

Python 代码如下：-

#!/usr/bin/python
import mysql.connector
import time
import logging
from PostCodeToLatLong import PostCodeToLatLong

API_KEY = 'fa9690c7e2927c7e9696d7xxxxxxxxxxx'

class AA_ForecastIOWeather(object):

    def __init__(self, codepoint_dir = '.'):
        self._db = None
        self.log = self._init_logging()
        self._forecastIO = API_KEY
        self.p2ll = PostCodeToLatLong(codepoint_dir)

    def __del__(self):
        self.disconnect_database()

    def connect_database():
        mysql.connector.connect(user='root', password='admin', host='localhost', port=3306, database='mydbname')

    def disconnect_database(self):
        self._db.commit()
        self._db.close()

    def _init_logging(self):
        log = logging.getLogger('AA_ForecastIOWeather')
        log.setLevel(logging.DEBUG)
        formatter = logging.Formatter('%(asctime)s-%(name)s(%(lineno)d)-%(levelname)s:%(message)s')
        handler = logging.StreamHandler()
        handler.setFormatter(formatter)
        log.addHandler(handler)
        return log



w = AA_ForecastIOWeather(codepoint_dir = '/registration/lib/codepoint')

Answer 1

设置 self._db:

变化：

def connect_database():
    mysql.connector.connect(user='root', password='admin', host='localhost', port=3306, database='mydbname')

进入：

def connect_database(self):
    self._db = mysql.connector.connect(user='root', password='admin', host='localhost', port=3306, database='mydbname')

当然需要调用connect_database()。如果没有在其他地方完成，这将是一个好地方：

def __init__(self, codepoint_dir = '.'):
    self._db = connect_database()

AttributeError: 'NoneType' object has no attribute 'commit'

AttributeError: 'NoneType' object has no attribute 'commit'

python

attributeerror

weather-api

python-3.x