Invalid ObjectId when saving to a ReferenceField in Mongo - django

Question

so I have this model set up with django and mongoengine.
class Product(Document):
product_id = IntField()
title = StringField(max_length=255)
sources = ListField(ReferenceField(Source, dbref = True))
class Source(Document):
source_id = IntField()
source_type = StringField(choices=settings.PARENT_TYPE_CHOICES, max_length=50)
name = StringField(max_length=255)
url = URLField(max_length=2000)
meta = {"allow_inheritance": True}
And in my scrapy pipeline I save the following data:
class SaveItemPipeline(object):
def process_item(self, item, spider):
product = item["product"]
product["sources"] = self.create_sources(product)
saved_product,created = Product.objects.get_or_create(**product)
return item
def create_sources(self,product):
temp_sources = []
for source in product["sources"]:
print source
if source["source_type"] == "user":
temp_source,created = UserSource.objects.get_or_create(**source)
elif source["source_type"] == "store":
temp_source,created = StoreSource.objects.get_or_create(**source)
elif source["source_type"] == "collection":
temp_source,created = CollectionSource.objects.get_or_create(**source)
temp_sources.append(temp_source.id)
return temp_sources
Howerver, when I run the scraper, on save it gives me this error:
raise ValidationError(message, errors=errors, field_name=field_name)
mongoengine.errors.ValidationError:
[ObjectId('55787a07516ddcf4d93cd4c6'),
ObjectId('55787b07516ddcf5aff06fa9'),
ObjectId('55787b07516ddcf5aff06faa')] is not a valid ObjectId
By the way the UserSource and StoreSource...all inherit from Source so they are just subclasses.However, am I doing anything wrong here, I don't understand why it is giving me that error when product gets created.
Thanks!

Answer 1

You can use this
class Source(Document):
source_id = IntField()
class Product(Document):
sources = ListField(ReferenceField(Source, dbref = True))
src, created = Source.objects.create(source_id=1)
pd, _ = Product.objects.create(sources=[src])
It works for me. I am using mongoengine 0.8.7, pymongo 2.8