DRF add non model fields just to update or create model instance

I have this issue at the moment with DRF.

I’m recieving extra fields that the model is not using. But those values will define the fields within the model.

{
"file_name": "test",
"file_type": "jpg",
"file": basex64 file,
"url_img": null
}

And i got this model

class imageModel(models.Model):
   id = models.AutoField(primary_key=True)
   url_img = models.textField(null=False)

All I need is to parse file_name and file_type to upload img to create a url_img and upload it on cloud. Is there a way to do this via DRF?

Answer

The DRF way of doing this is, explicitly define your extra fields in the serializer class.

class ImageModelSerializer(serializers.ModelSerializer):
    file_name = serializers.CharField(write_only=True)
    file_type = serializers.CharField(write_only=True)
    file = serializers.CharField(write_only=True)

    class Meta:
        model = ImageModel
        fields = "__all__"

Here, I have used serializers.CharField–(DRF Doc) since all of those data are strings (if not, choose serializer fields accordingly).

Also, setting write_only=True–(DRF Doc) will help us to omit those fields from the response.