/quiz/api/quiz/ 列“owner_id”中的空值的 IntegrityError 违反非空约束详细信息答案

【问题标题】：IntegrityError at /quiz/api/quiz/ null value in column "owner_id" violates not-null constraint DETAIL/quiz/api/quiz/ 列“owner_id”中的空值的 IntegrityError 违反非空约束详细信息
【发布时间】：2019-10-17 17:04:33
【问题描述】：

我正在尝试发布测验，但出现完整性错误。

所有者字段不为空而不是当前用户

serializer.py

class QuizSerializer(serializers.ModelSerializer):
    owner = serializers.PrimaryKeyRelatedField(read_only=True, default=serializers.CurrentUserDefault()
    )
    quiz_id = serializers.CharField(read_only=True, default='q'+secrets.token_hex(8))
    class Meta:
        model = Quiz
        fields = ['quiz_id', 'owner', 'title', 'description']

models.py

class Quiz(models.Model):

    quiz_id = models.CharField(max_length=50,primary_key=True,null=False)
    owner = models.ForeignKey(User, on_delete=models.CASCADE,null=False)
    title = models.CharField(max_length=50,null=False)
    description = models.TextField(max_length=200,blank=True)
    timestamp = models.DateTimeField(default=timezone.now)
    is_live = models.BooleanField(default=False)

views.py

【问题讨论】：

标签： python django django-rest-framework serialization

【解决方案1】：

使用HiddenField 而不是read_only=True，请参阅：https://www.django-rest-framework.org/api-guide/validators/#currentuserdefault 但这会使用户不在 GET 响应中， read_only 字段在输入中被忽略，参见https://www.django-rest-framework.org/api-guide/fields/#read_only 试试：

class QuizSerializer(serializers.ModelSerializer):
    owner = serializers.PrimaryKeyRelatedField(read_only=True)
    quiz_id = serializers.CharField(read_only=True)

    def save(**kwargs):
        kwargs['owner'] = self.context['request'].user
        kwargs['quiz_id'] = 'q'+secrets.token_hex(8)  # <-- you can have this as a default in model 
        super().save(**kwargs)

    class Meta:
        model = Quiz
        fields = ['quiz_id', 'owner', 'title', 'description']

【讨论】：