Empty list in appengine datastore: java vs python
- by lOranger
I have the following java model class in AppEngine:
public class Xyz ... {
@Persistent
private Set<Long> uvw;
}
When saving an object Xyz with an empty set uvw in Java, I get a "null" field (as listed in the appengine datastore viewer).
When I try to load the same object in python (through remote_api), as defined by the following python model class:
class Xys(db.Model):
uvw = db.ListProperty(int)
I get a "BadValueError: Property uvw is required".
When saving another object of the same class in python with an empty uvw list, the datastore viewer print a "missing" field.
Apparently empty lists storage handling differs between Java and python and lead to "incompatible" objects.
Thus my question: Is there a way to, either:
force Java to store an empty list as a "missing" field,
force Python to gracefully accept a "null" list as an empty list when loading the object?
Or any other suggestion on how to handle empty list field in both languages.
Thanks for your answers!
