is_main signal

backend/account/apps.py

@@ -5,3 +5,5 @@ class AccountConfig(AppConfig):
     default_auto_field = 'django.db.models.BigAutoField'
     name = 'account'
     verbose_name = 'اکانت'
+    def ready(self):
+        import account.signals

backend/account/models.py

@@ -129,7 +129,7 @@ class UserAddressModel(models.Model):
     city = models.CharField(max_length=30, verbose_name='شهر')
     province = models.CharField(max_length=30, verbose_name='استان')
     for_me = models.BooleanField(default=False, verbose_name='برای خود کاربر')
-    is_main = models.BooleanField(default=False)
+    is_main = models.BooleanField(default=False, verbose_name='ادرس اصلی کاربر')
 
     def __str__(self):
         return f"{self.user.phone}, {self.name}"

backend/account/signals.py

@@ -0,0 +1,10 @@
+from django.db import transaction
+from django.db.models.signals import post_save
+from django.dispatch import receiver
+from .models import UserAddressModel
+
+@receiver(post_save, sender=UserAddressModel)
+def ensure_single_main_address(sender, instance, **kwargs):
+    if instance.is_main:
+        with transaction.atomic():
+            UserAddressModel.objects.filter(user=instance.user).exclude(pk=instance.pk).update(is_main=False)