# coding=utf-8
"""
Django Extensions abstract base model classes.
"""
from django.db import models
from django.utils.translation import ugettext_lazy as _
from django_extensions.db.fields import (
AutoSlugField, CreationDateTimeField, ModificationDateTimeField,
)
try:
from django.utils.timezone import now as datetime_now
assert datetime_now
except ImportError:
import datetime
datetime_now = datetime.datetime.now
class TimeStampedModel(models.Model):
""" TimeStampedModel
An abstract base class model that provides self-managed "created" and
"modified" fields.
"""
created = CreationDateTimeField(_('created'))
modified = ModificationDateTimeField(_('modified'))
def save(self, **kwargs):
self.update_modified = kwargs.pop('update_modified', getattr(self, 'update_modified', True))
super(TimeStampedModel, self).save(**kwargs)
class Meta:
get_latest_by = 'modified'
ordering = ('-modified', '-created',)
abstract = True
class TitleDescriptionModel(models.Model):
""" TitleDescriptionModel
An abstract base class model that provides title and description fields.
"""
title = models.CharField(_('title'), max_length=255)
description = models.TextField(_('description'), blank=True, null=True)
class Meta:
abstract = True
class TitleSlugDescriptionModel(TitleDescriptionModel):
""" TitleSlugDescriptionModel
An abstract base class model that provides title and description fields
and a self-managed "slug" field that populates from the title.
"""
slug = AutoSlugField(_('slug'), populate_from='title')
class Meta:
abstract = True
class ActivatorQuerySet(models.query.QuerySet):
""" ActivatorQuerySet
Query set that returns statused results
"""
def active(self):
""" Returns active query set """
return self.filter(status=ActivatorModel.ACTIVE_STATUS)
def inactive(self):
""" Returns inactive query set """
return self.filter(status=ActivatorModel.INACTIVE_STATUS)
class ActivatorModelManager(models.Manager):
""" ActivatorModelManager
Manager to return instances of ActivatorModel: SomeModel.objects.active() / .inactive()
"""
def get_query_set(self):
""" Proxy to `get_queryset`, drop this when Django < 1.6 is no longer supported """
return self.get_queryset()
def get_queryset(self):
""" Use ActivatorQuerySet for all results """
return ActivatorQuerySet(model=self.model, using=self._db)
def active(self):
""" Returns active instances of ActivatorModel: SomeModel.objects.active(),
proxy to ActivatorQuerySet.active """
return self.get_query_set().active()
def inactive(self):
""" Returns inactive instances of ActivatorModel: SomeModel.objects.inactive(),
proxy to ActivatorQuerySet.inactive """
return self.get_query_set().inactive()
class ActivatorModel(models.Model):
""" ActivatorModel
An abstract base class model that provides activate and deactivate fields.
"""
INACTIVE_STATUS, ACTIVE_STATUS = range(2)
STATUS_CHOICES = (
(INACTIVE_STATUS, _('Inactive')),
(ACTIVE_STATUS, _('Active')),
)
status = models.IntegerField(_('status'), choices=STATUS_CHOICES, default=ACTIVE_STATUS)
activate_date = models.DateTimeField(blank=True, null=True, help_text=_('keep empty for an immediate activation'))
deactivate_date = models.DateTimeField(blank=True, null=True, help_text=_('keep empty for indefinite activation'))
objects = ActivatorModelManager()
class Meta:
ordering = ('status', '-activate_date',)
abstract = True
def save(self, *args, **kwargs):
if not self.activate_date:
self.activate_date = datetime_now()
super(ActivatorModel, self).save(*args, **kwargs)