新功能: 添加后端代码

backend/dvadmin/utils/validator.py

@@ -0,0 +1,73 @@
+# -*- coding: utf-8 -*-
+
+"""
+@author: 猿小天
+@contact: QQ:1638245306
+@Created on: 2021/6/2 002 17:03
+@Remark: 自定义验证器
+"""
+
+from django.db import DataError
+from rest_framework.exceptions import APIException
+from rest_framework.validators import UniqueValidator
+
+
+class CustomValidationError(APIException):
+    """
+    继承并重写验证器返回的结果,避免暴露字段
+    """
+
+    def __init__(self, detail):
+        self.detail = detail
+
+
+def qs_exists(queryset):
+    try:
+        return queryset.exists()
+    except (TypeError, ValueError, DataError):
+        return False
+
+
+def qs_filter(queryset, **kwargs):
+    try:
+        return queryset.filter(**kwargs)
+    except (TypeError, ValueError, DataError):
+        return queryset.none()
+
+
+class CustomUniqueValidator(UniqueValidator):
+    """
+    继承,重写必填字段的验证器结果,防止字段暴露
+    """
+
+    def filter_queryset(self, value, queryset, field_name):
+        """
+        Filter the queryset to all instances matching the given attribute.
+        """
+        filter_kwargs = {'%s__%s' % (field_name, self.lookup): value}
+        return qs_filter(queryset, **filter_kwargs)
+
+    def exclude_current_instance(self, queryset, instance):
+        """
+        If an instance is being updated, then do not include
+        that instance itself as a uniqueness conflict.
+        """
+        if instance is not None:
+            return queryset.exclude(pk=instance.pk)
+        return queryset
+
+    def __call__(self, value, serializer_field):
+        # Determine the underlying model field name. This may not be the
+        # same as the serializer field name if `source=<>` is set.
+        field_name = serializer_field.source_attrs[-1]
+        # Determine the existing instance, if this is an update operation.
+        instance = getattr(serializer_field.parent, 'instance', None)
+
+        queryset = self.queryset
+        queryset = self.filter_queryset(value, queryset, field_name)
+        queryset = self.exclude_current_instance(queryset, instance)
+        if qs_exists(queryset):
+            raise CustomValidationError(self.message)
+
+    def __repr__(self):
+        return super().__repr__()