如何通过将正常日期和日期时间与时区进行比较来过滤数据？

Posted 2021-04-10

我有一些数据存储在数据库中，我正在通过flask和flask-sqlalchemy访问和过滤。

我正在尝试根据start和end日期过滤数据，这些数据将被用作URL中request.args.get()的用户输入。在数据库中，数据为"2020-05-12T00:00:00+02:00"格式，当用户输入日期时，他将只输入日期而不是时间或时区（例如：2020-05-12）。因此，基于用户为start和end（包括end）输入的值，我想比较日期并返回这些值。但是，返回值必须具有原始日期格式

数据如下：

{
    "items": [
        {
            "id": 1,
            "value": 21.4,
            "start": "2020-05-12T00:00:00+02:00",
            "end": "2020-05-12T01:00:00+02:00",
            "country_code": "DE",
            "price_type": "DAY_AHEAD"
        },
        {
            "id": 2,
            "value": 18.93,
            "start": "2020-05-12T01:00:00+02:00",
            "end": "2020-05-12T02:00:00+02:00",
            "country_code": "DE",
            "price_type": "DAY_AHEAD"
        },
        {
            "id": 3,
            "value": 18.06,
            "start": "2020-05-13T02:00:00+02:00",
            "end": "2020-05-13T03:00:00+02:00",
            "country_code": "DE",
            "price_type": "DAY_AHEAD"
        },
        {
            "id": 4,
            "value": 17.05,
            "start": "2020-05-13T03:00:00+02:00",
            "end": "2020-05-13T04:00:00+02:00",
            "country_code": "DE",
            "price_type": "DAY_AHEAD"
        },
        {
            "id": 5,
            "value": 16.84,
            "start": "2020-05-14T04:00:00+02:00",
            "end": "2020-05-14T05:00:00+02:00",
            "country_code": "DE",
            "price_type": "DAY_AHEAD"
        },
        {
            "id": 6,
            "value": 19.3,
            "start": "2020-05-14T05:00:00+02:00",
            "end": "2020-05-14T06:00:00+02:00",
            "country_code": "DE",
            "price_type": "DAY_AHEAD"
        }]}

示例：

如果：

[start是2020-05-12＆end是2020-05-14，根据以上数据，必须返回以下数据：

{
    "items": [
        {
            "id": 1,
            "value": 21.4,
            "start": "2020-05-12T00:00:00+02:00",
            "end": "2020-05-12T01:00:00+02:00",
            "country_code": "DE",
            "price_type": "DAY_AHEAD"
        },
        {
            "id": 2,
            "value": 18.93,
            "start": "2020-05-12T01:00:00+02:00",
            "end": "2020-05-12T02:00:00+02:00",
            "country_code": "DE",
            "price_type": "DAY_AHEAD"
        },
        {
            "id": 3,
            "value": 18.06,
            "start": "2020-05-13T02:00:00+02:00",
            "end": "2020-05-13T03:00:00+02:00",
            "country_code": "DE",
            "price_type": "DAY_AHEAD"
        },
        {
            "id": 4,
            "value": 17.05,
            "start": "2020-05-13T03:00:00+02:00",
            "end": "2020-05-13T04:00:00+02:00",
            "country_code": "DE",
            "price_type": "DAY_AHEAD"
        },
        {
            "id": 5,
            "value": 16.84,
            "start": "2020-05-14T04:00:00+02:00",
            "end": "2020-05-14T05:00:00+02:00",
            "country_code": "DE",
            "price_type": "DAY_AHEAD"
        }]}

答案

如果您从request.args.get()中获取值，如下所示：

start_date = request.args.get('start')
end_date = request.args.get('end')

然后您可以使用dateutil.parser.parse将日期解析为isoformat()，然后对其进行过滤：

start_date = dateutil.parser.parse(filters['start']).isoformat()
end_date = dateutil.parser.parse(filters['end']).isoformat()
items = YourModel.query.filter(YourModel.start >= start_date).filter(YourModel.end <= end_date)