Custom Filter in Django admin

Question

I have a model as follows

class Person:
  name = models.CharField()
  city = models.CharField()
  phone = models.CharField()

I want to create a filter in the admin page, the filter should be based on phone, that is

valid phone(having 10 digits)
invalid phone

I don't want to create a validation. I just want to filter out who has a valid phone and invalid. Thanks

Answer 1

Create a custom list filter class. There's an example in the docs which can be adopted to your case.

from django.contrib import admin

class ValidPhoneListFilter(admin.SimpleListFilter):
    # Human-readable title which will be displayed in the
    # right admin sidebar just above the filter options.
    title = _('valid phone')

    parameter_name = 'valid_phone'

    def lookups(self, request, model_admin):
        return (
            ('valid', _('valid phone')),
            ('invalid', _('invalid phone')),
        )

    def queryset(self, request, queryset):
        if self.value() == 'valid':
            return queryset.filter(phone__regex=r'^\d{10}$')
        if self.value() == 'invalid':
            return queryset.exclude(phone__regex=r'^\d{10}$')

Then include your list filter class in list_filter for your model admin.

class PersonAdmin(admin.ModelAdmin):
    list_filter = (ValidPhoneListFilter,)

Answer 2

You could do something like

from django.core.validators import RegexValidator

phone_regex = RegexValidator(r'^[0-9]{10}$', 'Invalid phone number')

And in your model

phone = models.CharField(validators=[phone_regex])

This regex only checks if it is digits and that the length is 10. Modify it after your specific needs.

Hope this helps.

Good luck!