feat: add support for the field DateTimeRangeField from postgres.fields

[omargawdat]

Suggestion:

Wouldn't it be nice to add support for the field DateTimeRangeField from Postgres as this field is used a lot.

Screenshot

Code

from django.contrib.postgres.constraints import ExclusionConstraint
from django.contrib.postgres.fields import DateTimeRangeField, RangeOperators
from django.db import models
from django.db.models import Q

class Event(models.Model):
    title = models.CharField(max_length=200)
    timespan = DateTimeRangeField(null=True)
    capacity = models.PositiveIntegerField()
    cancelled = models.BooleanField(default=False)

    class Meta:
        constraints = [
            ExclusionConstraint(
                name="prevent_overlapping_events",
                expressions=[
                    ("timespan", RangeOperators.OVERLAPS),
                ],
                condition=Q(cancelled=False),
            ),
            models.CheckConstraint(
                check=Q(capacity__gte=1),
                name="capacity_gte_1"
            ),
        ]

Documentation URL

https://docs.djangoproject.com/en/5.1/ref/contrib/postgres/fields/#daterangefield

[omargawdat]

i have implemented a custom Widget to handle it, and it works fine for me:

from django import forms
from django.contrib import admin
from django.contrib.postgres.fields import DateTimeRangeField
from django.db.backends.postgresql.psycopg_any import DateTimeTZRange
from django.forms.widgets import MultiWidget
from unfold.admin import ModelAdmin
from unfold.widgets import UnfoldAdminSplitDateTimeWidget

from apps.schedule.models.test_model import Event


class UnfoldAdminDateTimeRangeWidget(MultiWidget):
    def __init__(self, attrs=None, error_messages=None):
        widgets = [
            UnfoldAdminSplitDateTimeWidget(attrs={'placeholder': 'Start date/time'}),
            UnfoldAdminSplitDateTimeWidget(attrs={'placeholder': 'End date/time'}),
        ]
        super().__init__(widgets, attrs)

    def decompress(self, value):
        if value:
            return [value.lower, value.upper]
        return [None, None]

    def value_from_datadict(self, data, files, name):
        value_0 = self.widgets[0].value_from_datadict(data, files, f'{name}_0')
        value_1 = self.widgets[1].value_from_datadict(data, files, f'{name}_1')

        # Improved error handling for partial dates
        if bool(value_0) ^ bool(value_1):  # XOR to check if only one value is provided
            if value_0:
                raise forms.ValidationError("End date is required when start date is provided")
            else:
                raise forms.ValidationError("Start date is required when end date is provided")

        if value_0 and value_1:
            return [value_0, value_1]
        return None


class UnfoldDateTimeRangeField(forms.MultiValueField):
    widget = UnfoldAdminDateTimeRangeWidget

    def __init__(self, **kwargs):
        kwargs.pop('default_bounds', None)
        required = kwargs.get('required', True)
        fields = (
            forms.SplitDateTimeField(required=required),
            forms.SplitDateTimeField(required=required),
        )
        super().__init__(
            fields=fields,
            require_all_fields=required,
            **kwargs
        )

    def compress(self, values):
        if not values:
            return None

        start_date, end_date = values

        # Check if only one date is provided
        if bool(start_date) ^ bool(end_date):
            if start_date:
                raise forms.ValidationError("End date is required when start date is provided")
            else:
                raise forms.ValidationError("Start date is required when end date is provided")

        if not any(values):
            return None

        try:
            if start_date and end_date and start_date > end_date:
                raise forms.ValidationError(
                    "Invalid date range - start date cannot be after end date"
                )
            return DateTimeTZRange(lower=start_date, upper=end_date)
        except TypeError:
            return None
        except ValueError as e:
            raise forms.ValidationError(str(e))


@admin.register(Event)
class EventAdmin(ModelAdmin):
    formfield_overrides = {
        DateTimeRangeField: {'form_class': UnfoldDateTimeRangeField},
    }

[lukasvinclav]

Please create PR and I will take a look. Thanks.

[omargawdat]

Please check the PR #954