Shaoster Glaze Django Admin

Django Admin Customization

Static Files

App-level admin static files (CSS, JS) live in <app>/static/admin/ and are served automatically in development when django.contrib.staticfiles is in INSTALLED_APPS and DEBUG=True. Reference them in an inline or ModelAdmin Media class:

class Media:
    css = {'all': ('admin/css/my_widget.css',)}
    js = ('admin/js/my_script.js',)

Inline Group IDs

Django derives an inline's form prefix from the related_name of the FK pointing to the parent model, not from the child model's class name. A GlazeCombinationLayer with combination = ForeignKey(..., related_name='layers') produces prefix layers, so the inline group element is id="layers-group" and new rows have class dynamic-layers. Keep this in mind when writing JavaScript targeting inline elements.

FK Widget Customization (RelatedFieldWidgetWrapper)

Two-stage wrapping pipeline for FK fields on inlines:

1. formfield_for_foreignkey — called first; right place to restrict queryset or swap widget entirely. Widget is a plain Select at this point.
2. formfield_for_dbfield — called after; wraps widget in RelatedFieldWidgetWrapper, which sets can_add_related, can_change_related, can_delete_related, can_view_related from related model's admin permissions.

Any can_*_related flags set inside formfield_for_foreignkey are silently overwritten. Override formfield_for_dbfield to set them post-wrap:

def formfield_for_foreignkey(self, db_field, request, **kwargs):
    if db_field.name == 'my_fk':
        kwargs['queryset'] = MyModel.objects.filter(...)  # queryset goes here
    return super().formfield_for_foreignkey(db_field, request, **kwargs)

def formfield_for_dbfield(self, db_field, request, **kwargs):
    field = super().formfield_for_dbfield(db_field, request, **kwargs)
    if db_field.name == 'my_fk' and hasattr(field, 'widget'):
        field.widget.can_delete_related = False  # widget flags go here
    return field

Debugging Admin Issues

Check the extension's documentation first before scanning source code or guessing. Many non-obvious constraints are documented explicitly (e.g. adminsortable2 documents that unique constraints on ordering fields cause swap failures on SQLite and MySQL).

Render the actual change page through the test client and inspect the HTML:

from django.test import Client
from django.contrib.auth import get_user_model

client = Client()
client.force_login(get_user_model().objects.get(is_superuser=True))
response = client.get('/admin/api/mymodel/1/change/')
html = response.content.decode()

print('JS loaded:', 'my_script.js' in html)
print('Delete button present:', 'delete-related' in html)

import re
print(re.findall(r'id="[^"]*-group"', html))

Tracing a formfield_for_* method:

import api.admin as api_admin

orig = api_admin.MyInline.formfield_for_foreignkey
def traced(self, db_field, request, **kwargs):
    field = orig(self, db_field, request, **kwargs)
    print(db_field.name, type(field.widget).__name__,
          getattr(field.widget, 'can_delete_related', '—'))
    return field
api_admin.MyInline.formfield_for_foreignkey = traced

client.get('/admin/api/mymodel/1/change/')

Note: outside a real request context, request.resolver_match is None, which crashes admin code reading URL kwargs. Use the test client to get a fully wired request.

Checking static file discoverability:

from django.contrib.staticfiles import finders
print(finders.find('admin/js/my_script.js'))  # None → file not on the path

Source: shaoster/glaze — distributed by TomeVault.