如何從 Django 中的發布請求中設置外鍵

Question

我有這個模型

class Driver(models.Model):
    first_name = models.CharField(max_length=250)
    last_name = models.CharField(max_length=250)
    created_at = models.DateTimeField(default=NOW)
    updated_at = models.DateTimeField(default=NOW)
    def __str__(self):
        return self.first_name      


class Vehicle(models.Model):
    driver_id = models.ForeignKey(Driver,on_delete=SET_NULL,unique=True,null=True, blank=True)
    make = models.CharField(max_length=150)
    model = models.CharField(max_length=150)
    plate_number = models.CharField(max_length=10,validators = [validate_plate_numberLATIN,validate_plate_numberCYRYLLIC], unique=True)
    created_at = models.DateTimeField(default=NOW)
    updated_at = models.DateTimeField(default=NOW)
    def __str__(self):
        return self.make

我嘗試在我的帖子請求中將外鍵設置為 Vehicle model

    @method_decorator(csrf_exempt, name='dispatch')
    def post(self,request,*args, **kwargs):
        body = json.loads(request.body.decode("utf-8"))
        newCar = Vehicle.objects.create(driver_id=body['driver_id'],make=body['make'],model=body['model'],plate_number=body['plate_number'])
        data = json.loads(serializers.serialize('json',[newCar]))
        return JsonResponse({'success':data})

並得到這個錯誤ValueError: Cannot assign "1": "Vehicle.driver_id" must be a "Driver" instance. 如何擺脫這個錯誤？ 如何創建 Driver 的實例並“發布”一個 ID？

Answer 1

可以通過將“_id”附加到字段名稱來訪問 ForeignKey 的原始值，這也可以用於使用原始值創建實例

Vehicle.objects.create(driver_id_id=body['driver_id'], ...)

Answer 2

你可以通過兩種方式做到這一點

1. 如果您需要代碼中某處的驅動程序實例，您可以使用此driver_instance = Driver.objects.get(pk=body['driver_id']) Vehicle.objects.create(driver_id=driver_instance,..)

Vehicle.objects.create(driver_id_id=body['driver_id'], ...)