Loopback issues when adding relations
Your foreign key is not correct, as per the documentation it should be,
Relation name: Camel case of the model name, for example, for the "supplier" model the relation is "supplier".
Foreign key: The relation name appended with ‘Id’, for example, for relation name "supplier" the default foreign key is "supplierId".
So in your case it should be
"foreignKey": "userId"https://docs.strongloop.com/display/public/LB/HasOne+relations
And you should use the slc relations instead of editing the json files.
I believe Container should inherit Model, not PersistedModel. By default, a Container is a folder inside a filesystem, so there is no choice of persisting it or not.
{ "name": "Container", "base": "Model",