python - Django Restful 中的 ListSerializer - 何时调用？

Question

我的 serializers.py 有以下代码:

from rest_framework import serializers

from django.db import transaction
from secdata_finder.models import File

class FileListSerializer(serializers.ListSerializer):
    @transaction.atomic
    def batch_save_files(file_data):
        files = [File(**data) for data in file_data]
        return File.objects.bulk_create(files)

    def create(self, validated_data):
        print("I am creating multiple rows!")
        return self.batch_save_files(validated_data)

class FileSerializer(serializers.ModelSerializer):
    class Meta:
        list_serializer_class = FileListSerializer
        model = File
        fields = (...) # omitted

我正在我的 Django 测试套件上试验它:

def test_file_post(self):
    request = self.factory.post('/path/file_query', {"many":False})
    request.data = {
        ... # omitted fields here
    }
    response = FileQuery.as_view()(request)

它打印I am creating multiple rows!，这是不应该发生的事情。

根据 docs :

... customize the create or update behavior of multiple objects. For these cases you can modify the class that is used when many=True is passed, by using the list_serializer_class option on the serializer Meta class.

所以我不明白什么？我在发布请求中传入了 many:False，但它仍然将 create 函数委托(delegate)给 FileListSerializer!

Answer 1

根据文档:

The ListSerializer class provides the behavior for serializing and validating multiple objects at once. You won't typically need to use ListSerializer directly, but should instead simply pass many=True when instantiating a serializer

您可以将 many=True 添加到您的序列化程序

class FileSerializer(serializers.ModelSerializer):

def __init__(self, *args, **kwargs):
    kwargs['many'] = kwargs.get('many', True)
    super().__init__(*args, **kwargs)

How do I create multiple model instances with Django Rest Framework? 的潜在骗局