Wagtail FormattedDateBlock

blocks.py

# -*- coding: utf-8 -*-
from __future__ import unicode_literals

from django import forms
from django.utils.functional import cached_property

from wagtail.wagtailcore.blocks.field_block import DateBlock


class FormattedDateBlock(DateBlock):

    def __init__(self, django_format=None, js_format=None, *args, **kwargs):
        self.django_format = django_format
        self.js_format = js_format
        super(FormattedDateBlock, self).__init__(*args, **kwargs)

    @cached_property
    def field(self):
        from .widgets import MyAdminDateInput
        field_kwargs = {'widget': MyAdminDateInput(
            format=self.django_format,
            js_format=self.js_format,
        )}
        field_kwargs.update(self.field_options)
        return forms.DateField(**field_kwargs)

example.py

    published_on = FormattedDateBlock(
        django_format='%d.%m.%Y.',
        js_format='d.m.Y.'
    )

widgets.py

# -*- coding: utf-8 -*-
from __future__ import unicode_literals

import json

from django.utils.formats import get_format

from wagtail.wagtailadmin.widgets import AdminDateInput


class MyAdminDateInput(AdminDateInput):

    def __init__(self, js_format='Y-m-d', *args, **kwargs):
        self.js_format = js_format
        super(MyAdminDateInput, self).__init__(*args, **kwargs)

    def render_js_init(self, id_, name, value):
        return 'initDateChooser({0}, {1});'.format(
            json.dumps(id_),
            json.dumps({
                'dayOfWeekStart': get_format('FIRST_DAY_OF_WEEK'),
                'format': self.js_format
            })
        )