Question

 class Item(models.Model):
 name = models.CharField(max_length=20)

 class Meals(models.Model):
 name = models.CharField(max_length=50)
 ingredients = models.ManyToManyField(Item, through='MealRecipe')


 class Menu(models.Model):
 name = models.CharField(max_length=50)
 meals = models.ManyToManyField(Meals,through='CompMenu')


 class CompMenu(models.Model):
 TYPE_COMP = (
     ('B', 'Breakfast'),
     ('L', 'Lunch'),
     ('D', 'Dinner')
 )
 menu = models.ForeignKey(Menu)
 meal = models.ForeignKey(Meals)
 type = models.CharField(max_length=1, choices=TYPE_COMP)

 class MealRecipe(models.Model):
 meal = models.ForeignKey(Meal)
 item = models.ForeignKey(Item)
 qty = models.IntegerField()

如果我需要序列化queryset我该怎么做，没有关于它的文档，我需要一个带有Item_id，Item_name，MealRecipe_qty的JSON。我必须序列化所有型号吗？我需要这个来根据所选菜单操作前端的配方数量。

 receipes = MealRecipe.objects.filter(meal__in=meals_of_menu)
 for receipe in receipes:
 name = receipe.item.name
 qty = receipe.qty

OR

 MealRecipe.objects.filter(meal__menu=some_menu_instance).distinct()

我无法弄清楚如何将此查询的结果传递给前端

Answer 1

根据您对Item_id，Item_name，MealRecipe_qty的要求，您需要序列化MealRecipe模型和Item模型。

还为MealRecipe模型中的项目提供相关名称

class MealRecipe(models.Model):
    meal = models.ForeignKey(Meal)
    item = models.ForeignKey(Item,related_name='qty')
    qty = models.IntegerField()

你的序列化工具将是

class MealRecipeSerializer(serializers.ModelSerializer):

    class Meta:
        model = MealRecipe
        fields = ('qty')

class ItemSerializer(serializers.ModelSerializer):

    qty = MealRecipeSerializer()
    class Meta:
        model = Item
        fields = ('id','name','qty')

此外，如果您将查询集传递给序列化程序，请执行MealRecipeSerializer(many=True)

Django Rest Framework有许多额外的字段序列化

1 个答案: