Properties should be inherited

[katarinasupe]

If I don't add property name to the class Stream, like this:

class User(Node):
    name: str = Field(index=True, unique=True, db=memgraph)


class Stream(User):
    id: str = Field(index=True, unique=True, db=memgraph)

then I get the following error:

twitch-app_1     |   File "/app/models.py", line 10, in <module>
twitch-app_1     |     class Stream(User):
twitch-app_1     |   File "/usr/local/lib/python3.8/site-packages/gqlalchemy/models.py", line 314, in __new__
twitch-app_1     |     raise GQLAlchemyDatabaseMissingInFieldError(
twitch-app_1     | gqlalchemy.exceptions.GQLAlchemyDatabaseMissingInFieldError

I expected that the name property would be inherited.

This works for now:

class User(Node):
    name: str = Field(index=True, unique=True, db=memgraph)


class Stream(User):
    name: Optional[str] = Field(index=True, unique=True, db=memgraph, label="User")
    id: str = Field(index=True, unique=True, db=memgraph)

[MasterMedo]

Oh, that's right. Because the database reference is removed from the property name once the User is created. It's an easy fix, when a subclass of Node is being created it can propagate the db object upwards. But then a user would have to define the Streamer as:

class Streamer(User, db):
    pass

The other option is what @jbajic and I talked earlier about, and that is creating a global instance of db that is going to be used everywhere. Very few users are going to use multiple databases, and we should cater the simplicity to the majority.

[katarinasupe]

Is it possible to add other properties to the Streamer then?
Because, when I try adding the db argument I get the following error:
TypeError: metaclass conflict: the metaclass of a derived class must be a (non-strict) subclass of the metaclasses of all its bases

[MasterMedo]

Oh, the functionality I mentioned is not implemented, it's a proposal.
But after giving it some thought, I think db arguments can be completely ignored when subclasses are created because the superclasses already created all constraints/indexes. I'll push a fix for this by the end of day.