Combine 2 separate filter fields into one sql query

[Fak3]

My frontend filtering form sends separate date and time fields. On the backend I need to validate both fields, merge them into one sql query Q(timestamp__gt=<datetime>), and exclude the separate date and time fields in sql query.

I wonder how I can achieve that without resorting to writing the whole custom_expression() query?

[Fak3]

The closest way I found still includes building custom expression. And uses custom list subclass hack to exclude date and time fields from filtering:

class Exclude(list):
    """ 
    A list which instance is always True, even if empty. 
    Tricks ninja.FilterSchema to skip pydantic field from generating queryset.
    """
    def __bool__(self):
        return True

class Filters(FilterSchema):
    date__gt: Optional[date | Literal["null", ""]] = Field(None, q=Exclude())
    time__gt: Optional[time | Literal["null", ""]] = Field(None, q=Exclude())

    def __call__(self):
        q = self._connect_fields()

        if self.date__gt and self.time__gt:
            q &= Q(timestamp__gt=datetime.combine(self.date__gt, self.time__gt))

        return Mymodel.objects.filter(q)

[vitalik]

would this work ?

class Filters(FilterSchema):
    date__gt: date = None
    time__gt: time = None

    def custom_expression(self) -> Q:
        q = Q()
        if self.date__gt and self.time__gt:
            q &= Q(timestamp__gt=datetime.combine(self.date__gt, self.time__gt))
        return q

[Fak3]

No, it won't work in the real environment. The issue is that there are multiple other fields that I want to filter on. So I have to call self._connect_fields() which will include date and time fields into queryset. So without my hack using custom list subclass, queryset will produce invalid sql filter.