Django admin page autocomplete on reverse ForeignKey - django

Question

Disclamer:
This is an edit question because I got some answers until now.
I would like to create an autocomplete field in InlineModelAdmin, with similar behavior as autocomplete_fields. I know, Django natively supports this only on ForeignKey, but I need it on the reverse side.
Is there a way - or a library that could do this?
I look into :
https://django-autocomplete-light.readthedocs.io/en/master/tutorial.html
https://django-grappelli.readthedocs.io/en/latest/customization.html
https://django-admin-autocomplete-all.readthedocs.io/en/latest/readme.html
But I didn't found this functionality...
Past question code:
I have models like this:
Models
class Customer(models.Model):
customer_ref = models.CharField(unique=True, max_length=50)
name = models.CharField(null=False, max_length=80)
country = models.CharField(null=True, max_length=50)
class Assortment(models.Model):
name = models.CharField(null=False, max_length=50)
customers = models.ManyToManyField(Customer, related_name='assortments', blank=True)
products = models.ManyToManyField(Product, related_name='assortments', blank=True)
class Subsidiary(models.Model):
subsidiary_ref = models.CharField(unique=True, max_length=50)
name = models.CharField(null=False, max_length=80)
address = models.TextField(null=True)
city = models.CharField(null=True, max_length=50)
coordinates_x = models.DecimalField(null=True, decimal_places=2, max_digits=6)
coordinates_y = models.DecimalField(null=True, decimal_places=2, max_digits=6)
phone_number = models.CharField(null=True, max_length=50)
frequency = models.ForeignKey(Frequency, on_delete=models.SET_NULL, null=True)
channel = models.CharField(null=True, blank=True, max_length=50)
subchannel = models.CharField(null=True, blank=True, max_length=50)
user = models.ForeignKey(User, related_name='subsidiaries', on_delete=models.SET_NULL, null=True)
day_planned = models.BooleanField(default=False)
customer = models.ForeignKey(Customer, on_delete=models.CASCADE, related_name='subsidiaries')
class Asset(models.Model):
identification = models.CharField(unique=True, max_length=50)
serial = models.CharField(max_length=50)
name = models.CharField(null=True, max_length=50)
subsidiary = models.ForeignKey(Subsidiary, related_name='assets', null=True, blank=True, on_delete=models.DO_NOTHING)
Admin
#admin.register(Customer)
class CustomerAdmin(admin.ModelAdmin):
list_display = ['customer_ref', 'name', 'country']
list_filter = ['country']
autocomplete_fields = ['assortments']
#admin.register(Subsidiary)
class SubsidiaryAdmin(admin.ModelAdmin):
exclude = ['day_planned']
list_display = ['subsidiary_ref', 'customer', 'name', 'address', 'phone_number', 'frequency', 'user']
list_editable = ['frequency', 'user']
list_filter = ['frequency', 'user']
search_fields = ['subsidiary_ref', 'customer__name', 'name']
autocomplete_fields = ['assets']
CustomerAdmin is 'working' without error but field 'assortments' is not visible.
SubsidiaryAdmin throws error :
<class 'mobileapp.admin.SubsidiaryAdmin'>: (admin.E038) The value of 'autocomplete_fields[0]' must be a foreign key or a many-to-many field.
witch is weird because I don't see any difference from the first example.
How to fix this?

Answer 1

assortments is not visible in the list page as you have set list_display to
list_display = ['customer_ref', 'name', 'country']
Since assortments is a many-to-many relationship, you have to write a custom ModelAdmin to display them.
As mentioned in the django docs, autocomplete_fields works only for FK & M2M fields of that model. In the AssetAdmin, you can set autocomplete for Subsidiary field.
#admin.register(Asset)
class AssetAdmin(admin.ModelAdmin):
autocomplete_fields = ['subsidiary']