如何将过滤器从下拉列表传递到 django-import-export 视图

Question

我了解如何通过具有return render(request, 'htmlname.html, {}) 的视图传递过滤器。 对于通过 django-import-export 导出选项导出数据的这种情况，我不知道该怎么做。我想从下拉选择中传递一个过滤器来下载要下载的数据。 我的看法

def ExportStudentsView(request):
    dataset = ExportStudentsResource().export(school = request.user.school,klass = ?????????)
    response = HttpResponse(dataset.xls, content_type='application/vnd.ms-excel')
    response['Content-Disposition'] = 'attachment; filename="All students.xls"'
    return response

我的资源

class ExportStudentsResource(resources.ModelResource):
    def export(self, queryset = None, *args, **kwargs):#this method helps capture the current user school
        queryset = Students.objects.filter(school = kwargs['school'],klass = kwargs['klass'])
        return super(ExportStudentsResource, self).export(queryset, *args, **kwargs)

    klass__name = fields.Field(attribute = 'klass__name',column_name='class')#Changes column name from school__name to school
    stream__name = fields.Field(attribute = 'stream__name',column_name='stream')
    gender__name = fields.Field(attribute = 'gender__name',column_name='gender')
    class Meta:
        model = Students
        fields = ('adm','name','kcpe','klass__name','stream__name','gender__name','notes')
        export_id_fields = ('adm',)
        export_order = ('adm','name','kcpe','klass__name','stream__name','gender__name','notes')

Answer 1

您可以采取几种方法。您选择的方法可能取决于这是“一次性”还是您需要可重用的类。我可能会赞成“方法 2”。

方法一

您可以在视图中过滤查询集，然后将其传递给导出：

def export_students(request):
  queryset = Students.objects.filter(school = kwargs['school'], klass = kwargs['klass'])
  # notice that the first arg to the Resource is a Queryset
  dataset = ExportStudentsResource().export(queryset)

方法二

覆盖资源上的get_queryset() 方法。您可以在实例化时设置 args 并将它们应用于查询：

class ExportStudentsResource(resources.ModelResource):

  def __init__(self, **kwargs):
    self.school = kwargs['school']
    self.klass = kwargs['klass']

  def get_queryset(self):
    return Students.objects.filter(school=self.school, klass=self.klass)

如果您查看 export() 的源代码，应该会更清楚地知道发生了什么，以及它们是如何结合在一起的。