from django.contrib import admin
from django.db import models
def getter_for_related_field(name, admin_order_field=None, short_description=None):
Create a function that can be attached to a ModelAdmin to use as a list_display field, e.g:
client__name = getter_for_related_field('client__name', short_description='Client')
related_names = name.split('__')
def getter(self, obj):
for related_name in related_names:
obj = getattr(obj, related_name)
getter.admin_order_field = admin_order_field or name
getter.short_description = short_description or related_names[-1].title().replace('_',' ')
Metaclass used by RelatedFieldAdmin to handle fetching of related field values.
We have to do this as a metaclass because Django checks that list_display fields are supported by the class.
def __getattr__(self, name):
if '__' in name:
getter = getter_for_related_field(name)
setattr(self, name, getter) # cache so we don't have to do this again
raise AttributeError # let missing attribute be handled normally
Version of ModelAdmin that can use related fields in list_display, e.g.:
list_display = ('address__city', 'address__country__country_code')
__metaclass__ = RelatedFieldAdminMetaclass
def queryset(self, request):
qs = super(RelatedFieldAdmin, self).queryset(request)
# include all related fields in queryset
select_related = [field.rsplit('__',1) for field in self.list_display if '__' in field]
# Include all foreign key fields in queryset.
# This is based on ChangeList.get_query_set().
# We have to duplicate it here because select_related() only works once.
# Can't just use list_select_related because we might have multiple__depth__fields it won't follow.
model = qs.model
for field_name in self.list_display:
field = model._meta.get_field(field_name)
if isinstance(field.rel, models.ManyToOneRel):
#### USAGE ####
# these fields will work automatically:
list_display = ('address__phone','address__country__country_code','address__foo')
# ... but you can also define them manually if you need to override short_description:
address__foo = getter_for_related_field('address__foo', short_description='Custom Name')