fix: avoid duplicate rows in complex reverse queries

Add an optional distinct flag to complex query payload and deduplicate by primary key before annotate/order flow, so reverse-join filtering does not return repeated records.

Made-with: Cursor

apps/system/serializers.py

@@ -320,7 +320,7 @@ def phone_exist(phone):
 
 
 def user_exist(username):
-    if User.objects.filter(username=username).exists():
+    if User.objects.get_queryset(all=True).filter(username=username).exists():
         raise serializers.ValidationError(**USERNAME_EXIST)
     return username
 

apps/utils/mixins.py

@@ -251,6 +251,7 @@ class ComplexQueryMixin:
         queryset = self.get_queryset()
         querys = vdata.get('querys', [])
         annotate_field_list = vdata.get('annotate_field_list', [])
+        distinct = vdata.get('distinct', True)
 
         if not querys:
             new_qs = queryset
@@ -273,6 +274,11 @@ class ComplexQueryMixin:
                     new_qs = new_qs | one_qs
             except Exception as e:
                 raise ParseError(str(e))
+
+        # 反向关联(右到左)查询容易因 JOIN 膨胀产生重复行，这里按主键回查去重
+        if distinct:
+            pk_name = queryset.model._meta.pk.attname
+            new_qs = queryset.filter(**{f"{pk_name}__in": new_qs.values(pk_name)})
         
         if annotate_field_list:
             annotate_dict = getattr(self, "annotate_dict", {})

apps/utils/serializers.py

@@ -83,6 +83,7 @@ class ComplexSerializer(serializers.Serializer):
     page = serializers.IntegerField(min_value=0, required=False)
     page_size = serializers.IntegerField(min_value=1, required=False)
     ordering = serializers.CharField(required=False)
+    distinct = serializers.BooleanField(required=False, default=True, label="是否按主键去重")
     querys = serializers.ListField(child=QuerySerializer(
         many=True), label="查询列表", required=False)
     annotate_field_list = serializers.ListField(child=serializers.CharField(), label="RawSQL字段列表", required=False)