djangorest：创建新父对象时如何设置相关字段可选

Question

在这里，我有两个模型：文档和Mysource，MySource将文档作为外国关键领域。为了总结该关系，用一个空数阵列的MySource对象初始化了文档，用户可以在其中创建一个新的MySource对象。

我正在尝试找出一种使用以下帖子请求创建文档对象的方法，其中MySource字段在开始时可以选择或空。

POST REQUEST
{
  "title": "Untitled",
  "templateId": 30,
  "question_blocks": [],
  "outline_blocks": [],
}

这将给出错误消息：“需要MySource字段”，

POST REQUEST
{
  "title": "Untitled",
  "templateId": 30,
  "question_blocks": [],
  "outline_blocks": [],
  "mysource": []
}

这将给出错误消息：直接分配到相关集的反向侧。使用adveress.set（）而不是

models.py

class Document(models.Model):
    id = HashidAutoField(primary_key=True)
    # TODO: blank, null to False
    user = models.ForeignKey(User, on_delete=models.CASCADE, blank=True, null=True)
    title = models.CharField(max_length=100, default="Untitled")
    template = models.CharField(max_length=100, default="")
    editorState = models.JSONField(default=[])
    updated = models.DateTimeField(auto_now=True)
    created = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return self.title

class MySource(models.Model):
    id = models.AutoField(primary_key=True)
    document = models.ForeignKey(
        Document,
        related_name="mysource",
        on_delete=models.CASCADE,
        null=True,
        blank=True,
    )
    documentId = models.CharField(max_length=50, default="", blank=True)
    url = models.CharField(max_length=500, default="", blank=True)
    title = models.CharField(max_length=500, default="", blank=True)
    publisher = models.CharField(max_length=500, default="", blank=True)
    desc = models.CharField(max_length=500, default="", blank=True)
    summary = models.CharField(max_length=500, default="", blank=True)

serializers.py

class DocumentListingField(serializers.RelatedField):
    def to_representation(self, instance):
        return model_to_dict(instance.document)

class MySourceSerializer(serializers.ModelSerializer):
    Document = DocumentListingField(many=False, read_only=True)

    class Meta:
        model = MySource
        fields = ("id", "url", "title", "publisher", "desc", "summary", "Document")

    def create(self, validated_data):
        # documentId = validated_data.pop("documentId")
        source = MySource.objects.create(
            document=Document.objects.get(id="J9DY2pE"), **validated_data
        )
        print(validated_data)
        source.save()
        return source


class DocumentSerializer(serializers.ModelSerializer):
    id = HashidSerializerCharField(source_field="documents.Document.id", read_only=True)
    question_blocks = QuestionBlockSerializer(many=True)
    outline_blocks = OutlineBlockSerializer(many=True)
    # TODO: disabling mysource until user foreign key is resolved
    mysource = MySourceSerializer(many=True)
    user = serializers.PrimaryKeyRelatedField(
        read_only=True, default=serializers.CurrentUserDefault()
    )

    class Meta:
        model = Document
        fields = "__all__"

    def create(self, validated_data):
        print(validated_data)
        question_blocks = validated_data.pop("question_blocks")
        outline_blocks = validated_data.pop("outline_blocks")
        document = Document.objects.create(**validated_data)
        for qBlock in question_blocks:
            QuestionBlock.objects.create(document=document, **qBlock)
        for oBlock in outline_blocks:
            OutlineBlock.objects.create(document=document, **oBlock)
        document.save()
        return document

Answer 1

我认为您需要将read_only = true属性添加到mySource字段中。

class DocumentSerializer(serializers.ModelSerializer):
    ...
    mysource = MySourceSerializer(many=True, read_only=True)
    ...