Question

我正在开发一个应用程序，它的功能之一是可以识别该设备，但有时无法收回任何东西。我正在使用的API可能有一个错误。

设备型号如下：

class DeviceSerializer(ModelSerializer):
def create(self, validated_data):
    # Check if exist
    device = Device.objects.filter(user=validated_data["user"], deviceId=validated_data['deviceId']).first()
    today = timezone.now()

    # If exist, update
    if device:
        device.tokenId = validated_data['tokenId']
        device.updated_at = today
        device.save()
        logger.info("[Device] Updated deviceID {} with token {} for user {}".format(
            validated_data['deviceId'],
            validated_data['tokenId'],
            validated_data["user"].username
        ))
    else:
        device = Device(**validated_data)
        device.save()
        logger.info("[Device] Created deviceID {} with token {} for user {}".format(
            validated_data['deviceId'],
            validated_data['tokenId'],
            validated_data["user"].username
        ))

    # Associate Device to ActiveSession
    active_session = ActiveSession.get_active_session(self.context.get('request'))
    active_session.device = device
    active_session.save()

    return device

class Meta:
    model = Device
    fields = ("id", "deviceModel", "deviceId", "packageId", "tokenId", "platformId")

而序列化器是：

active_session.device = device

我收到的错误来自此行AttributeError

我想为此[ERROR] 15:12 Internal Server Error: /api/device/ Traceback (most recent call last): File "/home/user/.local/lib/python2.7/site-packages/django/core/handlers/exception.py", line 39, in inner response = get_response(request) File "/home/user/.local/lib/python2.7/site-packages/django/core/handlers/base.py", line 187, in _get_response response = self.process_exception_by_middleware(e, request) File "/home/user/.local/lib/python2.7/site-packages/django/core/handlers/base.py", line 185, in _get_response response = wrapped_callback(request, *callback_args, **callback_kwargs) File "/home/user/.local/lib/python2.7/site-packages/django/views/decorators/csrf.py", line 58, in wrapped_view return view_func(*args, **kwargs) File "/home/user/.local/lib/python2.7/site-packages/rest_framework/viewsets.py", line 103, in view return self.dispatch(request, *args, **kwargs) File "/home/user/.local/lib/python2.7/site-packages/rest_framework/views.py", line 483, in dispatch response = self.handle_exception(exc) File "/home/user/.local/lib/python2.7/site-packages/rest_framework/views.py", line 443, in handle_exception self.raise_uncaught_exception(exc) File "/home/user/.local/lib/python2.7/site-packages/rest_framework/views.py", line 480, in dispatch response = handler(request, *args, **kwargs) File "/home/user/Downloads/ID/id/modules/api/views.py", line 69, in create self.perform_create(serializer) File "/home/user/Downloads/ID/id/modules/api/views.py", line 78, in perform_create serializer.save(user=self.request.user) File "/home/user/.local/lib/python2.7/site-packages/rest_framework/serializers.py", line 214, in save self.instance = self.create(validated_data) File "/home/user/Downloads/ID/id/modules/api/serializers.py", line 65, in create active_session.device_test = device AttributeError: 'NoneType' object has no attribute 'device_test'创建一个例外来面对这个错误。但是我的思想是开放的。

完整的回溯是这样的：

{{1}}

Answer 1

在许多情况下都可能发生AttributeError，但在尝试与相关模型进行错误关联时经常发生。在这种情况下，如果您的ActionveSessionModel与'device'具有不同的related_name，则不会找到'device'。

https://docs.djangoproject.com/en/2.2/topics/db/models/#be-careful-with-related-name-and-related-query-name

https://github.com/django/django/blob/master/django/db/models/fields/related_descriptors.py#L98

序列化器Django中的AttributeError

1 个答案: