多对多的嵌套序列化器

Question

我是 Python 和 Django 新手。我正在使用 Django-Rest-Framework 创建 api，我想序列化可以接受以下格式的 json 的数据：

{
"ingredients": ["Sugar","Egg"],
"name": "Cake",
"description": "Dinner Food",
"directions": "direction1"
}

但是我可以使用以下格式将数据保存在数据库中：

{
"ingredients": [{"name":"Cake"},{"name":"Egg"}],
"name": "Rice",
"description": "Dinner Food",
"directions": "direction1"
}

我不确定如何将字典转换为设置字段。我知道列表字段和列表序列化器，但不知道如何使用它们。是否可以使用模型序列化器来做到这一点？

序列化器.py

class IngredientSerializer(serializers.ModelSerializer):

    class Meta:
        model = Ingredient
        fields = '__all__'


class RecipeSerializer(serializers.ModelSerializer):
    ingredients = IngredientSerializer(many=True)

        class Meta:
            model = Recipe
            fields = '__all__'

    def create(self, validated_data):
        ingredients_data = validated_data.pop('ingredients')
        print(ingredients_data)
        recipe = Recipe.objects.create(**validated_data)
        for ingredient in ingredients_data:
            ingredient, created = Ingredient.objects.get_or_create(name=ingredient['name'])
            recipe.ingredients.add(ingredient)
        return recipe

模型.py

class Ingredient(models.Model):
    name = models.CharField(max_length=100)

    def __str__(self):
        return self.name


class Recipe(models.Model):
    name = models.CharField(max_length=100)
    description = models.TextField(blank=True, null=True)
    directions = models.TextField()
    ingredients = models.ManyToManyField(Ingredient)

    def __str__(self):
        return self.name

视图.py

class RecipieView(viewsets.ModelViewSet):
    queryset = Recipe.objects.all()
    serializer_class = RecipeSerializer


class IngredientView(viewsets.ModelViewSet):
    queryset = Ingredient.objects.all()
    serializer_class = IngredientSerializer  

Answer 1

我建议您使用两种不同的序列化器来实现创建目的和其他目的。请参阅下面的代码片段，
views.py

class RecipieView(viewsets.ModelViewSet):
    queryset = Recipe.objects.all()
    serializer_class = RecipeMainSerializer

    def get_serializer_class(self):
        if self.action == 'create':
            return RecipeCreateSerializer
        return RecipeMainSerializer

序列化器.py

class RecipeCreateSerializer(serializers.ModelSerializer):
    ingredients = serializers.ListField(write_only=True)

    class Meta:
        model = Recipe
        fields = '__all__'

    def create(self, validated_data):
        ingredients_data = validated_data.pop('ingredients')
        recipe = Recipe.objects.create(**validated_data)
        for ingredient in ingredients_data:
            ingredient, created = Ingredient.objects.get_or_create(name=ingredient)
            recipe.ingredients.add(ingredient)
        return recipe


class RecipeMainSerializer(serializers.ModelSerializer):
    ingredients = IngredientSerializer(many=True)

    class Meta:
        model = Recipe
        fields = '__all__'