Django/Graphene 突变错误 "you need to pass a valid Django model" 无法修复

Question

下面是我正在使用的 Django/Graphene 示例的 RDBMS 图：

下面是我的 model.py 应用代码：

from django.db import models

# Create your models here.
class ProductCategory(models.Model):
  category = models.CharField(max_length=50)
  parentCategory = models.ForeignKey('self',null=True, on_delete=models.CASCADE)

class Product(models.Model):
  productNumber= models.CharField(max_length=50)
  description = models.CharField(max_length=50)
  productCategory= models.ForeignKey('product.ProductCategory', on_delete=models.PROTECT)

以下是应用的 Schema.py：

import graphene
from graphene_django import DjangoObjectType

from .models import Product, ProductCategory

class ProductType(DjangoObjectType):
  class Meta:
    model = Product

class ProductCategoryType(DjangoObjectType):
  class Meta:
    model = ProductCategory

class Query(graphene.ObjectType):
  products = graphene.List(ProductType)
  productCategories = graphene.List(ProductCategoryType)

  def resolve_products(self, info):
      return Product.objects.all()
  def resolve_productCategories(self,info):
      return ProductCategory.objects.all()


class CreateProductCategory(DjangoObjectType):
  productCategory = graphene.Field(ProductCategoryType)

  class Arguments:
    category = graphene.String(required=True)
    parentCategory = graphene.Int()
  
  def mutate(self, info, category, parentCategory):
    productCategory = ProductCategory(category = category, parentCategory = parentCategory)
    productCategory.save()
    return CreateProductCategory(productCategory=productCategory)

    return CreateProductCategory(category=category,parentCategory=parentCategory)

class Mutation(graphene.ObjectType):
  createProductCategory= CreateProductCategory.Field()

没有突变代码，查询请求工作正常，如下图所示

但是加了突变码会报错，我是菜鸟也搞不懂自己做错了什么。请帮忙！！

AssertionError：您需要在 CreateProductCategory.Meta 中传递有效的 Django 模型，收到“None”。

Answer 1

问题是：class CreateProductCategory(DjangoObjectType)

您需要继承 graphene.Mutation，而不是 DjangoObjectType，才能进行突变。

正确：class CreateProductCategory(graphene.Mutation) `

Django/Graphene 突变错误 "you need to pass a valid Django model" 无法修复

Django/Graphene Mutation error "you need to pass a valid Django model" can't fix it

django

graphene-django