class ProductVariation(Priced):
"""
A combination of selected options from
``SHOP_OPTION_TYPE_CHOICES`` for a ``Product`` instance.
"""
product = models.ForeignKey("Product", related_name="variations")
default = models.BooleanField(_("Default"))
image = models.ForeignKey("ProductImage",
verbose_name=_("Image"),
null=True,
blank=True)
objects = managers.ProductVariationManager()
__metaclass__ = ProductVariationMetaclass
class Meta:
ordering = ("-default", )
def __unicode__(self):
"""
Display the option names and values for the variation.
"""
options = []
for field in self.option_fields():
if getattr(self, field.name) is not None:
options.append(
"%s: %s" %
(unicode(field.verbose_name), getattr(self, field.name)))
return ("%s %s" % (unicode(self.product), ", ".join(options))).strip()
def save(self, *args, **kwargs):
"""
Use the variation's ID as the SKU when the variation is first
created.
"""
super(ProductVariation, self).save(*args, **kwargs)
if not self.sku:
self.sku = self.id
self.save()
def get_absolute_url(self):
return self.product.get_absolute_url()
@classmethod
def option_fields(cls):
"""
Returns each of the model fields that are dynamically created
from ``SHOP_OPTION_TYPE_CHOICES`` in
``ProductVariationMetaclass``.
"""
all_fields = cls._meta.fields
return [f for f in all_fields if isinstance(f, fields.OptionField)]
def options(self):
"""
Returns the field values of each of the model fields that are
dynamically created from ``SHOP_OPTION_TYPE_CHOICES`` in
``ProductVariationMetaclass``.
"""
return [getattr(self, field.name) for field in self.option_fields()]
def live_num_in_stock(self):
"""
Returns the live number in stock, which is
``self.num_in_stock - num in carts``. Also caches the value
for subsequent lookups.
"""
if self.num_in_stock is None:
return None
if not hasattr(self, "_cached_num_in_stock"):
num_in_stock = self.num_in_stock
items = CartItem.objects.filter(sku=self.sku)
aggregate = items.aggregate(quantity_sum=models.Sum("quantity"))
num_in_carts = aggregate["quantity_sum"]
if num_in_carts is not None:
num_in_stock = num_in_stock - num_in_carts
self._cached_num_in_stock = num_in_stock
return self._cached_num_in_stock
def has_stock(self, quantity=1):
"""
Returns ``True`` if the given quantity is in stock, by checking
against ``live_num_in_stock``. ``True`` is returned when
``num_in_stock`` is ``None`` which is how stock control is
disabled.
"""
live = self.live_num_in_stock()
return live is None or quantity == 0 or live >= quantity
def update_stock(self, quantity):
"""
Update the stock amount - called when an order is complete.
Also update the denormalised stock amount of the product if
this is the default variation.
"""
if self.num_in_stock is not None:
self.num_in_stock += quantity
self.save()
if self.default:
self.product.num_in_stock = self.num_in_stock
self.product.save()
class ProductVariation(with_metaclass(ProductVariationMetaclass, Priced)):
"""
A combination of selected options from
``SHOP_OPTION_TYPE_CHOICES`` for a ``Product`` instance.
"""
product = models.ForeignKey("Product",
on_delete=models.DO_NOTHING,
related_name="variations")
default = models.BooleanField(_("Default"), default=False)
image = models.ForeignKey("ProductImage",
verbose_name=_("Image"),
null=True,
blank=True,
on_delete=models.SET_NULL)
objects = managers.ProductVariationManager()
class Meta:
ordering = ("-default", )
def __str__(self):
"""
Display the option names and values for the variation.
"""
options = []
for field in self.option_fields():
name = getattr(self, field.name)
if name is not None:
option = u"%s: %s" % (field.verbose_name, name)
options.append(option)
result = u"%s %s" % (str(self.product), u", ".join(options))
return result.strip()
def save(self, *args, **kwargs):
"""
Use the variation's ID as the SKU when the variation is first
created.
"""
super(ProductVariation, self).save(*args, **kwargs)
if not self.sku:
self.sku = self.id
self.save()
def get_absolute_url(self):
return self.product.get_absolute_url()
def validate_unique(self, *args, **kwargs):
"""
Overridden to ensure SKU is unique per site, which can't be
defined by ``Meta.unique_together`` since it can't span
relationships.
"""
super(ProductVariation, self).validate_unique(*args, **kwargs)
if self.__class__.objects.exclude(id=self.id).filter(
product__site_id=self.product.site_id, sku=self.sku).exists():
raise ValidationError({"sku": _("SKU is not unique")})
@classmethod
def option_fields(cls):
"""
Returns each of the model fields that are dynamically created
from ``SHOP_OPTION_TYPE_CHOICES`` in
``ProductVariationMetaclass``.
"""
all_fields = cls._meta.fields
return [
f for f in all_fields if isinstance(f, fields.OptionField)
and not hasattr(f, "translated_field")
]
def options(self):
"""
Returns the field values of each of the model fields that are
dynamically created from ``SHOP_OPTION_TYPE_CHOICES`` in
``ProductVariationMetaclass``.
"""
return [getattr(self, field.name) for field in self.option_fields()]
def live_num_in_stock(self):
"""
Returns the live number in stock, which is
``self.num_in_stock - num in carts``. Also caches the value
for subsequent lookups.
"""
if self.num_in_stock is None:
return None
if not hasattr(self, "_cached_num_in_stock"):
num_in_stock = self.num_in_stock
carts = Cart.objects.current()
items = CartItem.objects.filter(sku=self.sku, cart__in=carts)
aggregate = items.aggregate(quantity_sum=models.Sum("quantity"))
num_in_carts = aggregate["quantity_sum"]
if num_in_carts is not None:
num_in_stock = num_in_stock - num_in_carts
self._cached_num_in_stock = num_in_stock
return self._cached_num_in_stock
def has_stock(self, quantity=1):
"""
Returns ``True`` if the given quantity is in stock, by checking
against ``live_num_in_stock``. ``True`` is returned when
``num_in_stock`` is ``None`` which is how stock control is
disabled.
"""
live = self.live_num_in_stock()
return live is None or quantity == 0 or live >= quantity
def update_stock(self, quantity):
"""
Update the stock amount - called when an order is complete.
Also update the denormalised stock amount of the product if
this is the default variation.
"""
if self.num_in_stock is not None:
self.num_in_stock += quantity
self.save()
if self.default:
self.product.num_in_stock = self.num_in_stock
self.product.save()
