models.rst

Model Mixins and Base Classes

.. module:: django_goodies.models

CommonInfoMixin

CommonInfoMixin is a model mixin class that provides:

• Standard user and datetime fields: user_created, user_modified, date_created, date_modified.
• An overridden objects Manager, an instance of the custom :class:`~django_goodies.models.managers.CommonInfoManager` that provides access to the custom :class:`~django_goodies.models.managers.CommonInfoQuerySet`.
• Support for :ref:`commoninfomixin-ownership-checking` on an instance and via CommonInfoQuerySet.
• A simple :ref:`default implementation <commoninfomixin-object-permissions>` of :doc:`/topics/permissions` via ownership checking.

.. automethod:: save

.. automethod:: owned_by

.. seealso::

    :class:`~django_goodies.models.managers.CommonInfoManager`
        The custom Manager exposed by the ``objects`` attribute.

    :class:`~django_goodies.models.managers.CommonInfoQuerySet`
        The custom QuerySet exposed by ``CommonInfoManager``.

    :class:`~django_goodies.forms.CommonInfoForm`
        A ``ModelForm`` subclass to act as a base for ``CommonInfoMixin`` model forms.

ArchivableMixin

ArchivableMixin is a model mixin class that provides:

• An is_archived Boolean field, defaulting to False.
• An overridden objects Manager, an instance of the custom :class:`~django_goodies.models.managers.ArchivableManager` that provides access to the custom :class:`~django_goodies.models.managers.ArchivableQuerySet`.
• Two additional managers, live and archived, with default querysets filtered to unarchived (is_archived == False) and archived (is_archived == True) records by default. Both are also instances of :class:`~django_goodies.models.managers.ArchivableManager`.
• Support for :ref:`archiving and unarchiving <archivablemixin-archiving-unarchiving>`, both at the instance level and in bulk via :class:`~django_goodies.models.managers.ArchivableQuerySet`.

.. automethod:: archive

.. automethod:: unarchive

.. seealso::

    :class:`~django_goodies.models.managers.ArchivableManager`
        The custom Manager exposed by the ``objects``, ``live`` and ``archived`` attributes.

    :class:`~django_goodies.models.managers.ArchivableQuerySet`
        The custom QuerySet exposed by ``ArchivableManager``.

VersioningMixin

VersioningMixin is a model mixin class that provides:

• A version field that is automatically incremented on every save.
• An overridden objects Manager, an instance of the custom :class:`~django_goodies.models.managers.VersioningManager` that provides access to the custom :class:`~django_goodies.models.managers.VersioningQuerySet`.

.. automethod:: save

.. exception:: VersioningMixin.AmbiguousVersionError

    A subclass of :exc:`~django_goodies.exceptions.ModelAmbiguousVersionError` specific to the :class:`VersioningMixin` class. Raised when attempting to access the ``version`` field after it has been atomically incremented.

.. seealso::

    :class:`~django_goodies.models.managers.VersioningManager`
        The custom Manager exposed by the ``objects`` attribute.

    :class:`~django_goodies.models.managers.VersioningQuerySet`
        The custom QuerySet exposed by ``VersioningManager``.

StaticAbstract

StaticAbstract is a combination of :class:`CommonInfoMixin`, :class:`ArchivableMixin` and :class:`VersioningMixin`. It is designed as an abstract base class for models, rather than a mixin itself. It includes all the fields, as well as custom objects, live and archived managers, and provides access to all the functionality offered by each of the mixins.