Fix use of ip_address_validators for Django 5.1+ (#9180)

* Fix use of ip_address_validators for Django 5.0+

* Change affected django version to 5.1

Author: kiendang

rest_framework/compat.py

@@ -169,6 +169,21 @@ def parse_header_parameters(line):
         }
 
 
+if django.VERSION >= (5, 1):
+    # Django 5.1+: use the stock ip_address_validators function
+    # Note: Before Django 5.1, ip_address_validators returns a tuple containing
+    #       1) the list of validators and 2) the error message. Starting from
+    #       Django 5.1 ip_address_validators only returns the list of validators
+    from django.core.validators import ip_address_validators
+else:
+    # Django <= 5.1: create a compatibility shim for ip_address_validators
+    from django.core.validators import \
+        ip_address_validators as _ip_address_validators
+
+    def ip_address_validators(protocol, unpack_ipv4):
+        return _ip_address_validators(protocol, unpack_ipv4)[0]
+
+
 # `separators` argument to `json.dumps()` differs between 2.x and 3.x
 # See: https://bugs.python.org/issue22767
 SHORT_SEPARATORS = (',', ':')

rest_framework/fields.py

@@ -16,7 +16,7 @@
 from django.core.validators import (
     EmailValidator, MaxLengthValidator, MaxValueValidator, MinLengthValidator,
     MinValueValidator, ProhibitNullCharactersValidator, RegexValidator,
-    URLValidator, ip_address_validators
+    URLValidator
 )
 from django.forms import FilePathField as DjangoFilePathField
 from django.forms import ImageField as DjangoImageField
@@ -36,6 +36,7 @@
     pytz = None
 
 from rest_framework import ISO_8601
+from rest_framework.compat import ip_address_validators
 from rest_framework.exceptions import ErrorDetail, ValidationError
 from rest_framework.settings import api_settings
 from rest_framework.utils import html, humanize_datetime, json, representation
@@ -866,7 +867,7 @@ def __init__(self, protocol='both', **kwargs):
         self.protocol = protocol.lower()
         self.unpack_ipv4 = (self.protocol == 'both')
         super().__init__(**kwargs)
-        validators, error_message = ip_address_validators(protocol, self.unpack_ipv4)
+        validators = ip_address_validators(protocol, self.unpack_ipv4)
         self.validators.extend(validators)
 
     def to_internal_value(self, data):