Django - 如何将json反序列化为嵌套对象

Question

我遇到以下问题。我需要使用在json中发布的数据创建一个复杂的对象。在models.py文件，我有一个名为“公司”的主要对象：

class Company(models.Model): 
    name = models.CharField(max_length=255) 
    descr = models.CharField(max_length=255) 

    def __str__(self): 
     return self.name 

然后，我有“楼”：

class Building(models.Model): 
    name = models.CharField(max_length=255) 
    city = models.CharField(max_length=255) 
    location = models.TextField() 
    company= models.ForeignKey("Company", related_name="buildings", on_delete=models.CASCADE) 

与其他几类

等等（即“落地” ，“区域”，“房间”）。

我从POST请求得到的JSON是：

{ 
    "id": 1, 
    "buildings": [{ 
     "id": 3, 
     "floors": [{ 
      "id": 1, 
      "floor": -1, 
      "descr": "underground", 
      "building": 3 
     }], 
     "areas": [{ 
      "id": 1, 
      "rooms": [{ 
       "id": 1, 
       "floor": 1, 
       "area": 1, 
       "descr": "First Room" 
      }], 
      "descr": "Dev area", 
      "building": { 
       "id": 3, 
       "name": "Sede", 
       "city": "Rome", 
       "location": "mylocation", 
       "company": { 
        "id": 1, 
        "name": "Test", 
        "descr": "Test" 
       } 
      } 
     }], 
     "name": "Sede", 
     "city": "Rome", 
     "location": "mylocation", 
     "company": 1 
    }], 
    "name": "Test", 
    "descr": "Test" 
} 

当我尝试创建从JSON，我收到了“公司”的对象，它不仅创造了以下内容：

{ 
    "id": 1, 
    "buildings": [], 
    "name": "Test", 
    "descr": "Test" 
} 

而不是完整的结构。

我的序列化有以下几种：

class BuildingSerializer(serializers.ModelSerializer): 
    floors= FloorSerializer(read_only=True, many=True) 
    areas = AreaSerializer(read_only=True, many=True) 
    class Meta: 
     model = Building 
     fields = '__all__' 
     read_only_fields = ('id',) 

class CompanySerializer(serializers.ModelSerializer): 
    buildings= BuildingSerializer(read_only=True, many=True) 
    class Meta: 
     model = Company 
     fields = '__all__' 
     read_only_fields = ('id',) 

我怎样才能解决这个问题？

P.S.我知道json有点多余！

Answer 1

99％的时间，当你没有得到嵌套的数据是因为你发送一个JSON负载与表单内容类型。

通过将Content-Type标头设置为application/json并在您的客户端中明确表明您要发送JSON，并且应该解决内容问题。

Answer 2

您指定的建筑物作为一个只读字段：http://www.django-rest-framework.org/api-guide/serializers/#specifying-read-only-fields

尝试在串行去除参数：

class BuildingSerializer(serializers.ModelSerializer): 
    floors= FloorSerializer(many=True) 
    aree = AreaSerializer(many=True) 
    class Meta: 
     model = Building 
     fields = '__all__' 
     read_only_fields = ('id',) 

class CompanySerializer(serializers.ModelSerializer): 
    buildings= BuildingSerializer(many=True) 
    class Meta: 
     model = Company 
     fields = '__all__' 
     read_only_fields = ('id',)