Comment 0 for bug 1013566

Hello,

It seems that there is a small issue when we use an AbstractModel.
By the way, I'm not sure if it is really destined to be used as I'm not able to find any usage in addons.
It's a pity because it allows to really modularize some things.

As instance, I tried to create a model with the "sequence" responsibility :

class Sequencable(AbstractModel):

    _name = 'abstract.sequencable'

    _order = 'sequence'

    _columns = {
        'sequence': fields.integer('Sequence')
    }

    _defaults = {
        'sequence': 1000
    }

Then, in the models where I want a sequence, I just have to inherit from 'abstract.sequencable'.

class ModelA(Model):

    _name = 'model.a'
    _inherit = ['abstract.sequencable', 'other.inheritance']

    _columns = {...}

class ModelB(TransientModel):

    _name = 'model.b'
    _inherit = 'abstract.sequencable'

    _columns = {...}

First, do you see any reason not to do that ?

The once issue I've encountered is that _auto is set to False in TransientModel, and is not forced to True in Model and TransientModel

In orm.py with some cuts :
class AbstractModel(BaseModel):
    _auto = False # don't create any database backend for AbstractModels
    _register = False # not visible in ORM registry, meant to be python-inherited only

class Model(BaseModel):
    _register = False # not visible in ORM registry, meant to be python-inherited only
    _transient = False # True in a TransientModel

So as a result, I have to declare _auto = True in every materialized models. So with my model.a I had to to:
class ModelA(Model):

    _name = 'model.a'
    _inherit = ['abstract.sequencable', 'other.inheritance']
   _auto = True

    _columns = {...}

As Model and TransiantModel are supposed to be concrete models, I think that they have to be _auto = True by default even if they are "_inherit"-ing an AbstractModel.

So the base model classes would be (without docstrings):
class Model(BaseModel):
    _register = False # not visible in ORM registry, meant to be python-inherited only
    _transient = False # True in a TransientModel
    _auto = True # create database backend for Models

class TransientModel(BaseModel):
    _register = False # not visible in ORM registry, meant to be python-inherited only
    _transient = True
    _auto = True # create database backend for TransientModels

class AbstractModel(BaseModel):
    _auto = False # don't create any database backend for AbstractModels
    _register = False # not visible in ORM registry, meant to be python-inherited only

Do you agree with that ?

Thanks
Guewen