erf django restframework Got AttributeError when attempting to get a value for field `image

I am facing this error when trying to open the endpoint (http://127.0.0.1:8000/api/metrics/) I am using django restramework (drf), software and category enpoints are working fine, but the metric endpoint is giving the following error:

Error

{
    "message": "Got AttributeError when attempting to get a value for field `image_id` on serializer `SoftwareSerializer`.\nThe serializer field might be named incorrectly and not match any attribute or key on the `Category` instance.\nOriginal exception text was: 'Category' object has no attribute 'image'.",
    "code": null,
    "status_code": 406
}

Models

class Category(models.Model):
    name = models.CharField(max_length=256, blank=True)
    created_datetime = models.DateTimeField(auto_now_add=True, verbose_name="تاریخ ایجاد ")
    update_datetime  = models.DateTimeField(auto_now=True, verbose_name="تاریخ بروزرسانی ")

    def __str__(self):
        return self.name

class Metric(models.Model):
    title = models.CharField(max_length=254)
    categorymetric = models.ForeignKey("main.Category",on_delete=models.SET_NULL,null=True)

    def __str__(self):
        return self.title

class Software(models.Model):
    software_name   = models.CharField(max_length=150, default="software_name", null=False, verbose_name="اسم نرم افزار")
    created_datetime = models.DateTimeField(auto_now_add=True, verbose_name="تاریخ ایجاد ")
    update_datetime  = models.DateTimeField(auto_now=True, verbose_name="تاریخ بروزرسانی ")
    image            = models.ForeignKey("main.Image", on_delete=models.SET_NULL, blank=True, null=True)
    created_by       = models.ForeignKey(settings.AUTH_USER_MODEL,on_delete=models.CASCADE, null=True)
    
    class Meta:
         verbose_name = "software"
         verbose_name_plural = "softwares"

    def __str__(self) :
          return self.software_name

Views

class CategoryViewSet(ModelViewSet):
    serializer_class = CategorySerializer
    pagination_class = None
    queryset = Category.objects.all()

class SoftwareViewSet(ModelViewSet):
    serializer_class = SoftwareSerializer
    pagination_class = None
    queryset = Software.objects.all()
    permission_classes = ( IsAuthenticated, )
    
    def perform_create(self, serializer):
        serializer.save(created_by=self.request.user)

class MetricViewSet(ModelViewSet):
    serializer_class = MetricSerializer
    pagination_class = None
    queryset = Metric.objects.all()

Serializers

class MetricSerializer(serializers.ModelSerializer):
    categorymetric = SoftwareSerializer(read_only=True)
    categorymetric_id = serializers.PrimaryKeyRelatedField(queryset=Category.objects.all(), source='Categorymetric')
    class Meta:
        model = Metric
        fields = ['id', 'title', 'categorymetric','categorymetric_id']

class CategorySerializer(serializers.ModelSerializer):
    class Meta :
        model =Category
        fields = ['id','name','created_datetime','update_datetime']

class SoftwareSerializer(serializers.ModelSerializer):
    image = ImageSerializer(read_only=True)
    image_id = serializers.PrimaryKeyRelatedField(queryset=Image.objects.all(), source='image')
    
    class Meta:
        model = Software
        fields = ['id', 'software_name','created_datetime','update_datetime','image','image_id', 'created_by']
        depth = 1

I searched alot but could not find the solution, Anyone have any idea what's the solution? Thanks in advance

CodePudding user response：

You used the wrong serializer for the categorymetric.

Instead of

class MetricSerializer(serializers.ModelSerializer):
    categorymetric = SoftwareSerializer(read_only=True)

it should be

class MetricSerializer(serializers.ModelSerializer):
    categorymetric = CategorySerializer(read_only=True)