TypeError：'int'对象不是可迭代的序列化器Django序列化器，一对多

Question

我面临一个奇怪的情况，以下是我的模型代码。

class Sector(models.Model):
    sector_name = models.CharField(max_length=255, null=False)
    sector_desc = models.CharField(max_length=1024, null=False)

    def __set__(self):
        return "{} - {}".format(self.sector_name, self.sector_desc)


class TrailCompany(models.Model):
    sector = models.ForeignKey(Sector, on_delete=models.CASCADE, related_name="sector_id")
    comp_name = models.CharField(max_length=255, null=False)
    comp_desc = models.CharField(max_length=1024, null=False)

    def __set__(self):
        return "{} - {}".format(self.sector, self.comp_name, self.comp_desc)


class Trail(models.Model):
    company = models.ForeignKey(TrailCompany, on_delete=models.CASCADE, related_name="company_id")
    trail_id = models.CharField(max_length=255, null=False)
    tri = models.CharField(max_length=255, null=False)
    exp_pdufa = models.CharField(max_length=255, null=False)

    def __set__(self):
        return "{} - {}".format(self.company, self.exp_pdufa, self.trail_id, self.tri, self.exp_pdufa)

以下是我的序列化程序代码，

class SectorSerializer(serializers.ModelSerializer):

    class Meta:
        model = Sector
        fields = '__all__'


class TrailCompanySerializer(serializers.ModelSerializer):
    sectors = SectorSerializer(source="sector_id", many=True)

    class Meta:
        model = TrailCompany
        fields = '__all__'


class TrailSerializer(serializers.ModelSerializer):
    companies = TrailCompanySerializer(source="company_id", many=True)

    class Meta:
        model = Trail
        fields = '__all__'

[当我尝试对对象进行序列化时，出现了所述错误，

trail_query = Trail.objects.all()
        trails = TrailSerializer(trail_query, many=True)
        return Response({"success": True, 'trails': trails.data})

[请帮助我找出并解决问题。谢谢。

Answer 1

看起来您的错误在以下行中：

companies = TrailCompanySerializer(source="company_id", many=True)

从Trail的角度来看，

Trail <> TrailCompany是一对一的关系。例如。 Trail仅知道与之相关的一个TrailCompany。因此，您不需要many=True属性。

我也认为来源应该是company，而不是company_id。 company_id是主键，而company是相关对象