DRF框架中链表数据通过ModelSerializer深度查询方法汇总

DRF框架中链表数据通过ModelSerializer深度查询方法汇总

一.准备测试和理解准备

创建类

class Test1(models.Model):
    id = models.IntegerField(primary_key=True)
    test_2_id= models.ForeignKey(to='Test2',on_delete='id') #这里有的创建失败了哈哈忘了会自动补全id
class Test2(models.Model):
    id = models.IntegerField(primary_key=True)
    name = models.CharField(max_length=60)

生成表单数据

Test1

id	test_2_id_id
1	1
2	2

Test2

id	name
1	名字1
2	名字2

二.深度查询通过Test1获得Test2的name而不是id

方法一

models.py

#对于test1添加方法
class Test1(models.Model):
    id = models.IntegerField(primary_key=True)
    test_2_id= models.ForeignKey(to='Test2',on_delete='id')
    @property
    def get_test2_name(self):
        return self.test_2_id.name

views.py

from rest_framework.serializers import ModelSerializer
from app.models import Test1
class Test_ser(ModelSerializer):
    class Meta:
        model = Test1  # 这里会把Test1面的所有名称空间存在的都进行导入
        fields = ('id','get_test2_name')
class Test(APIView):
    def get(self,request):
        test1_objs = Test1.objects.all()
        test1_ser = Test_ser(instance=test1_objs,many=True).data
        for a in test1_ser:
            print(a)
        return HttpResponse('ok')

方法二

views.py

from rest_framework.serializers import ModelSerializer
from app.models import Test1,Test2
class Test_2_ser(ModelSerializer):
    class Meta:
        model = Test2
        fields = '__all__'
class Test_ser(ModelSerializer):
    test_2_id = Test_2_ser()  #test_2_id为Test1与Test2关联的字段
    class Meta:
        model = Test1
        fields = '__all__'
class Test(APIView):
    def get(self,request):
        test1_objs = Test1.objects.all()
        test1_ser = Test_ser(instance=test1_objs,many=True).data
        for a in test1_ser:
            print(a)
        return HttpResponse('ok')

方法三

#通过添加自定义字段
class Test_ser(ModelSerializer):
    test_2_name = SerializerMethodField() #自定义字段名称
    def get_test_2_name(self,model):  #这里方法名必须get_字段名称
        return model.test_2_id.name    #对于获取字段后的返回值
    class Meta:
        model = Test1
        fields = '__all__'
class Test(APIView):
    def get(self,request):
        test1_objs = Test1.objects.all()
        test1_ser = Test_ser(instance=test1_objs,many=True).data
        for a in test1_ser:
            print(a)
        return HttpResponse('ok')

方法四

#通过添加自定义字段
class Test_ser(ModelSerializer):
    image_url=serializers.CharField(source='test_2_id.name') #test1中的test_2_id.name的内容
    class Meta:
        model = Test1
        fields = '__all__'
class Test(APIView):
    def get(self,request):
        test1_objs = Test1.objects.all()
        test1_ser = Test_ser(instance=test1_objs,many=True,context={"request":request}).data
        for a in test1_ser:
            print(a)
        return HttpResponse('ok')