模型类序列化器

7.1 序列化多条数据

序列化器

class StudentModelSerializer(serializers.ModelSerializer):
    """学生信息序列化器"""

    class Meta:
        model = studentsInfo  # 必填
        fields = ["id", "name", "sex", "age", "classroom", "info"]  # 必填
        read_only_fields = ["id"]  # 选填
        exclude = []  # 选填，列表里的字段不会序列化

视图

class StudentView(View):

    def get(self, request):
        """序列化器-模型序列化器的调用"""
        # 1.获取数据集
        queryset = studentsInfo.objects.all()

        # 2.实例化序列化器，得到序列化器对象
        serializer = StudentModelSerializer(instance=queryset, many=True)

        # 3.调用序列化器对象的data属性获取序列i化后的数据
        data = serializer.data

        # 4.响应数据
        return JsonResponse(data=data, status=200, safe=False, json_dumps_params={"ensure_ascii": False})

响应结果

[
    {
        "id": 1,
        "name": "小明",
        "sex": "男",
        "age": 22,
        "classroom": "301",
        "info": "这个人很懒，什么也没有留下"
    },
    {
        "id": 2,
        "name": "小红",
        "sex": "女",
        "age": 18,
        "classroom": "301",
        "info": "这个人很懒，什么也没有留下"
    },
    {
        "id": 3,
        "name": "张三",
        "sex": "男",
        "age": 25,
        "classroom": "307",
        "info": "这个人很懒，什么也没有留下"
    },
    {
        "id": 4,
        "name": "李四",
        "sex": "男",
        "age": 24,
        "classroom": "308",
        "info": "这个人很懒，什么也没有留下"
    },
    {
        "id": 5,
        "name": "闵麒良",
        "sex": "男",
        "age": 23,
        "classroom": "310",
        "info": "河工胡歌"
    },
    {
        "id": 12,
        "name": "孙明辉",
        "sex": "男",
        "age": 23,
        "classroom": "333",
        "info": "这个人很懒，什么都没有留下"
    },
    {
        "id": 15,
        "name": "彭于晏",
        "sex": "女",
        "age": 0,
        "classroom": "000",
        "info": "要做个猛男，要猛！"
    }
]

7.2 添加额外字段

序列化器

class StudentModelSerializer(serializers.ModelSerializer):
    """学生信息序列化器"""
	nickname = serializers.CharField(read_only=True)
    class Meta:
        model = studentsInfo  # 必填
        fields = ["id", "name", "sex", "age", "classroom", "info","nickname"]  # 必填
        read_only_fields = ["id"]  # 选填

视图

class StudentView(View):

    def get(self, request):
        """序列化器-模型序列化器的调用"""
        # 1.获取数据集
        queryset = studentsInfo.objects.all()
        for data in queryset:
        	data.nickname = "胡歌"

        # 2.实例化序列化器，得到序列化器对象
        serializer = StudentModelSerializer(instance=queryset, many=True)

        # 3.调用序列化器对象的data属性获取序列i化后的数据
        data = serializer.data

        # 4.响应数据
        return JsonResponse(data=data, status=200, safe=False, json_dumps_params={"ensure_ascii": False})

响应结果

[
    {
        "id": 1,
        "name": "小明",
        "sex": "男",
        "age": 22,
        "classroom": "301",
        "info": "这个人很懒，什么也没有留下",
        "nickname": "胡歌"
    },
    {
        "id": 2,
        "name": "小红",
        "sex": "女",
        "age": 18,
        "classroom": "301",
        "info": "这个人很懒，什么也没有留下",
        "nickname": "胡歌"
    },
    {
        "id": 3,
        "name": "张三",
        "sex": "男",
        "age": 25,
        "classroom": "307",
        "info": "这个人很懒，什么也没有留下",
        "nickname": "胡歌"
    },
    {
        "id": 4,
        "name": "李四",
        "sex": "男",
        "age": 24,
        "classroom": "308",
        "info": "这个人很懒，什么也没有留下",
        "nickname": "胡歌"
    },
    {
        "id": 5,
        "name": "闵麒良",
        "sex": "男",
        "age": 23,
        "classroom": "310",
        "info": "河工胡歌",
        "nickname": "胡歌"
    },
    {
        "id": 12,
        "name": "孙明辉",
        "sex": "男",
        "age": 23,
        "classroom": "333",
        "info": "这个人很懒，什么都没有留下",
        "nickname": "胡歌"
    },
    {
        "id": 15,
        "name": "彭于晏",
        "sex": "女",
        "age": 0,
        "classroom": "000",
        "info": "要做个猛男，要猛！",
        "nickname": "胡歌"
    }
]

7.3 字段选项验证

序列化器

class StudentModelSerializer(serializers.ModelSerializer):
    """学生信息序列化器"""
	nickname = serializers.CharField(read_only=True)
    class Meta:
        model = studentsInfo  # 必填
        fields = ["id", "name", "sex", "age", "classroom", "info","nickname"]  # 必填
        read_only_fields = ["id"]  # 选填
        extra_kwargs = {
            "age": {
                "min_value": 0,
                "max_value": 100,
                "error_messages": {
                    "min_value": "the age must be age>=0",
                    "max_value": "the age must be age<=100"
                }
            }
        }  # 选填

视图

class StudentView(View):
    def get(self, request):
        """反序列化-采用字段选项来验证数据-验证失败不抛出异常"""
        # 1.接收客户端提交的数据
        # data = json.loads(request.body)
        data = {
            "name": "张家祥",
            "age": 120,
            "sex": "男",
            "classroom": "444",
            "info": "这个人很胖"
        }
        # 2.实例化序列化器，获取序列化对象
        serializer = StudentModelSerializer(data=data)
        # 3.调用序列化器进行数据验证
        ret = serializer.is_valid()
        # 4.获取验证以后的结果
        if ret:
            return JsonResponse(dict(serializer.validated_data), safe=False)
        else:
            return JsonResponse(dict(serializer.errors), safe=False)
        # 5.操作数据库

        # 6.返回结果

响应结果

{
    "age": [
        "the age must be age<=100"
    ]
}

7.4 反序列化(添加数据)

视图

class StudentView(View):
    def get(self, request):
        """反序列化-采用字段选项来验证数据-验证失败抛出异常"""
        # 1.接收客户端提交的数据
        # data = json.loads(request.body)
        data = {
            "name": "彭于晏",
            "age": 30,
            "sex": "男",
            "classroom": "666",
            "info": "要做个猛男，要猛！"
        }
        # 2.实例化序列化器，获取序列化对象
        serializer = StudentModelSerializer(data=data)
        # 3.调用序列化器进行数据验证
        serializer.is_valid(raise_exception=True)  # 抛出异常，代码不会往下执
        # 4.获取验证以后的结果,操作数据库
        serializer.save()  # 如果在实例化序列化器对象的时候没有传入instance属性，则自动调用序列化器的create钩子函数方法
        # 5.返回结果
        return JsonResponse(serializer.data, status=201)

响应结果

{
    "id": 16,
    "name": "范玉才",
    "sex": "男",
    "age": 23,
    "classroom": "310",
    "info": "要做个猛男，要猛！"
}

数据库变化

注意：模型类序列化器内部已经实现了create和update方法，无需我们实现，如果要是有特殊需求可以重写，但是验证函数要自己定义，和普通序列化器的使用方法相同，修改数据的话和之前的视图一样，这里不再一一实现。