from nosql-rest-preprocessor.models import BaseModel

class AddressModel(BaseModel):
    required_attributes = {'street', 'city', 'plz'}

    # if you specify optional attributes explicitely, it will 
    # not allow anything but these and the required ones
    optional_attributes = {'location'}

class UserModel(BaseModel):
    required_attributes = {'firstName', 'lastName', 'email'}
    immutable_attributes = {'id'}
    private_attributes = {'password', 'salt'}

    # will use AddressModel to validate, merge and prepare the content of the 'address' attribute
    sub_models: {
        'address': AddressModel
    }

new_user_from_request = {
    "firstName": "Sepp",
    "lastName": "Huber",
    "email": "sepp.huber@fancepants.com",
    "address": {
        "street": "Bakerstreet 1",
        "city": "London",
        "plz": "12345"
    }
}

# checks required_attributes and raises ValidationError if something's amiss
UserModel.validate(new_user_from_request)

user_obj_from_db = db.fetch_user_by_email("sepp.huber@fancepants.com")

# strips out any non-public attributes
response_obj = UserModel.prepare_response(user_obj_from_db)

return Response(response_obj)

from nosql-rest-preprocessor.models import BaseModel
from nosql-rest-preprocessor.resolvers import resolve, ResolveWith

class AddressModel(BaseModel):
    ...

class UserModel(BaseModel):
    ...

    resolved_attributes = {
        'address' = ResolveWith(lookup_func=SomeDB.find_address_by_key, model=AddressModel)
    }

...

user = {
    "name": "cookie_m0nster",
    "address": "foreign_key_for_address"
}

resolved_obj = resolve(UserModel, user)
# resolved_obj['address'] is now replaced by the dict fetched by SomeDB.find_address_by_key('foreign_key_for_address')

from nosql-rest-preprocessor.utils import one_of, all_of, either_of

# use helper methods to define attribute validation more precisely
class SomeModel(BaseModel):
    required_attributes = {
        'A',
        one_of('B', 'C'),
        either_of('D', 'E')
    }

    optional_attributes = {
        all_of('F', 'G'),
        either_of('H', 'I')
    }