Django - 通过验证过滤范围内的日期答案

【问题标题】：Django - Filter a date within a range with validationDjango - 通过验证过滤范围内的日期
【发布时间】：2016-08-14 14:25:27
【问题描述】：

我在模型中有一个名为“session_start”的 DateTimeField。我正在尝试过滤一个日期范围内的 session_start 字段。

Model.py

class TimeCard(models.Model):
    profile = models.ForeignKey(settings.AUTH_USER_MODEL)
    session_start = models.DateTimeField()

过滤器需要满足以下条件：

在“start_date”和“end_date”范围内过滤“session_start”字段。
验证“start_date”和“end_date”字段。这意味着“start_date”值应该是“end_date”值之前的日期。如果传递了无效数据，则根据默认值返回查询集。默认值为 -

start_date = 从今天开始的 30 天。

end_date = 今天。

我编写了以下代码来过滤“start_date”和“end_date”之间的范围内的“session_start”字段。现在我陷入了检查 start_date 大于 end_date 的条件。我该怎么做才能进行验证？

filter.py

class TimeCardFilter(filters.FilterSet):

    start_date = django_filters.DateTimeFilter(name="session_start", lookup_type='gte')
    end_date = django_filters.DateTimeFilter(name="session_start", lookup_type='lte')

    class Meta:
        model = TimeCard
        fields = ['profile', 'start_date', 'end_date']

【问题讨论】：

标签： python django django-rest-framework django-filter

【解决方案1】：

您实际上可以在django-filters Filtersets 中使用django forms，因此您可以在表单的clean() 方法中管理验证。您的 filter.py 可能看起来像这样：

import django_filters
from app.models import TimeCard
from django import forms


class TimeCardFilter(django_filters.FilterSet):

    start_date = django_filters.DateTimeFilter(
        name="session_start",
        lookup_type="gte")
    end_date = django_filters.DateTimeFilter(
        name="session_start",
        lookup_type="lte")

    class Meta:
        model = TimeCard
        form = TimeCardForm


class TimeCardForm(forms.Form):

    def clean(self):
        cleaned_data = super(TimeCardForm, self).clean()
        start_date = cleaned_data.get("start_date")
        end_date = cleaned_data.get("end_date")

        if start_date > end_date:
            self._errors['start_date'] = self._errors.get('start_date', [])
            self._errors['start_date'].append("Start date must be before end date.")

        return cleaned_data

【讨论】：

【解决方案2】：

Based on the source code，您的选择可能有限。看起来您最好的选择是覆盖 qs 属性。

class TimeCardFilter(filters.FilterSet):

    start_date = django_filters.DateTimeFilter(name="session_start", lookup_type='gte')
    end_date = django_filters.DateTimeFilter(name="session_start", lookup_type='lte')

    @property
    def qs(self):
        # Parent class defines a property _qs which represents the updated queryset
        if hasattr(self, '_qs'):
           return self._qs
        # qs property is the place that FilterSet generates a query string.
        # it finds the values in the self.form.cleaned_data or self.form[name].value()
        orig_start = self.form.cleaned_data['session_start']
        orig_end = self.form.cleaned_data['session_end']

        # Your conditional logic would go here.
        if orig_start > orig_end:
           # You'll need real values here, these clearly are fake.
           self.form.cleaned_data['session_start'] = now()-30 * 24 * 3600
           self.form.cleaned_data['session_end'] = now()

        # Be sure to return FilterSet's actual QS.
        return super(TimeCardFilter, self).qs()

    class Meta:
        model = TimeCard
        fields = ['profile', 'start_date', 'end_date']

【讨论】：