yourlabs / djhacker

Metacode more with Django

Django-Hacker: customize default django forms

Basic usage

Install with pip install djhacker and then:

import djhacker

djhacker.formfield(
    YourModel.your_field,
    form_class=YourFormField,
    custom_form_field_kwarg='something',
)

This will make any Django ModelForm render a YourFormField(custom_form_field_kwarg='something') by default, plus whatever other kwargs it wants to add, you won't have to use any specific model form, this will work natively in the admin for instance.

Note

form_class is optionnal, you may as well just pass kwargs and not change the default form class for a form field.

Custom formfield callback

You can register custom form field for model field types:

@djhacker.register(models.ForeignKey)
def custom_fk_formfield(model_field, **kwargs):
    return dict(
        form_class=YourFormField,
        custom_form_field_kwarg=something,
        **kwargs,
    )

# you don't need to pass extra arguments anymore for ForeignKey fields:
djhacker.formfield(YourModel.some_fk, queryset=Some.objects.all())

Widget Script attributes

Another thing Django is not doing anytime soon is letting you customize script tags. Which means there's no easy way to combine Widget.Media.js and any of the nice new script tag attributes, including, but not limited to:

• async, defer: good to control when your script is loaded
• type="module": to load a script as an EcmaScript Module (ESM) and use imports

Let's have this anyway, first patch Django's Media render_js:

import djhacker
djhacker.media_script_attributes()

Then, let's customize a script tag:

class YourWidget(forms.Widget):
    class Media:
        js = [
            'your/script.js[type=module][defer=true]',
        ]

It will render as such:

<script src="/static/your/script.js" type="module" defer="true"></script>

Upgrade

To v0.2.x

Registered callbacks now return a simple dict with the form field class in form_class.

@djhacker.register(models.ForeignKey)
def custom_fk_formfield(model_field, **kwargs):
    return YourFormField, {
        'custom_form_field_kwarg': 'something',
        **kwargs,
    )

Becomes:

@djhacker.register(models.ForeignKey)
def custom_fk_formfield(model_field, **kwargs):
    return dict(
        form_class=YourFormField,
        custom_form_field_kwarg=something,
        **kwargs,
    )