diff --git a/registrasion/controllers/cart.py b/registrasion/controllers/cart.py index 20bd6b5c..dbf7e8a0 100644 --- a/registrasion/controllers/cart.py +++ b/registrasion/controllers/cart.py @@ -1,6 +1,6 @@ import collections +import contextlib import datetime -import discount import functools import itertools @@ -8,6 +8,7 @@ from django.core.exceptions import ObjectDoesNotExist from django.core.exceptions import ValidationError from django.db import transaction from django.db.models import Max +from django.db.models import Q from django.utils import timezone from registrasion.exceptions import CartValidationError @@ -15,19 +16,27 @@ from registrasion.models import commerce from registrasion.models import conditions from registrasion.models import inventory -from category import CategoryController -from conditions import ConditionController -from product import ProductController +from .category import CategoryController +from .discount import DiscountController +from .flag import FlagController +from .product import ProductController def _modifies_cart(func): ''' Decorator that makes the wrapped function raise ValidationError - if we're doing something that could modify the cart. ''' + if we're doing something that could modify the cart. + + It also wraps the execution of this function in a database transaction, + and marks the boundaries of a cart operations batch. + ''' @functools.wraps(func) def inner(self, *a, **k): self._fail_if_cart_is_not_active() - return func(self, *a, **k) + with transaction.atomic(): + with CartController.operations_batch(self.cart.user) as mark: + mark.mark = True # Marker that we've modified the cart + return func(self, *a, **k) return inner @@ -55,13 +64,65 @@ class CartController(object): ) return cls(existing) + # Marks the carts that are currently in batches + _FOR_USER = {} + _BATCH_COUNT = collections.defaultdict(int) + _MODIFIED_CARTS = set() + + class _ModificationMarker(object): + pass + + @classmethod + @contextlib.contextmanager + def operations_batch(cls, user): + ''' Marks the boundary for a batch of operations on a user's cart. + + These markers can be nested. Only on exiting the outermost marker will + a batch be ended. + + When a batch is ended, discounts are recalculated, and the cart's + revision is increased. + ''' + + if user not in cls._FOR_USER: + _ctrl = cls.for_user(user) + cls._FOR_USER[user] = (_ctrl, _ctrl.cart.id) + + ctrl, _id = cls._FOR_USER[user] + + cls._BATCH_COUNT[_id] += 1 + try: + success = False + + marker = cls._ModificationMarker() + yield marker + + if hasattr(marker, "mark"): + cls._MODIFIED_CARTS.add(_id) + + success = True + finally: + + cls._BATCH_COUNT[_id] -= 1 + + # Only end on the outermost batch marker, and only if + # it excited cleanly, and a modification occurred + modified = _id in cls._MODIFIED_CARTS + outermost = cls._BATCH_COUNT[_id] == 0 + if modified and outermost and success: + ctrl._end_batch() + cls._MODIFIED_CARTS.remove(_id) + + # Clear out the cache on the outermost operation + if outermost: + del cls._FOR_USER[user] + def _fail_if_cart_is_not_active(self): self.cart.refresh_from_db() if self.cart.status != commerce.Cart.STATUS_ACTIVE: raise ValidationError("You can only amend active carts.") - @_modifies_cart - def extend_reservation(self): + def _autoextend_reservation(self): ''' Updates the cart's time last updated value, which is used to determine whether the cart has reserved the items and discounts it holds. ''' @@ -83,21 +144,25 @@ class CartController(object): self.cart.time_last_updated = timezone.now() self.cart.reservation_duration = max(reservations) - @_modifies_cart - def end_batch(self): + def _end_batch(self): ''' Performs operations that occur occur at the end of a batch of product changes/voucher applications etc. - THIS SHOULD BE PRIVATE + + You need to call this after you've finished modifying the user's cart. + This is normally done by wrapping a block of code using + ``operations_batch``. + ''' - self.recalculate_discounts() + self.cart.refresh_from_db() - self.extend_reservation() + self._recalculate_discounts() + + self._autoextend_reservation() self.cart.revision += 1 self.cart.save() @_modifies_cart - @transaction.atomic def set_quantities(self, product_quantities): ''' Sets the quantities on each of the products on each of the products specified. Raises an exception (ValidationError) if a limit @@ -122,24 +187,28 @@ class CartController(object): # Validate that the limits we're adding are OK self._test_limits(all_product_quantities) + new_items = [] + products = [] for product, quantity in product_quantities: - try: - product_item = commerce.ProductItem.objects.get( - cart=self.cart, - product=product, - ) - product_item.quantity = quantity - product_item.save() - except ObjectDoesNotExist: - commerce.ProductItem.objects.create( - cart=self.cart, - product=product, - quantity=quantity, - ) + products.append(product) - items_in_cart.filter(quantity=0).delete() + if quantity == 0: + continue - self.end_batch() + item = commerce.ProductItem( + cart=self.cart, + product=product, + quantity=quantity, + ) + new_items.append(item) + + to_delete = ( + Q(quantity=0) | + Q(product__in=products) + ) + + items_in_cart.filter(to_delete).delete() + commerce.ProductItem.objects.bulk_create(new_items) def _test_limits(self, product_quantities): ''' Tests that the quantity changes we intend to make do not violate @@ -147,13 +216,17 @@ class CartController(object): errors = [] + # Pre-annotate products + products = [p for (p, q) in product_quantities] + r = ProductController.attach_user_remainders(self.cart.user, products) + with_remainders = dict((p, p) for p in r) + # Test each product limit here for product, quantity in product_quantities: if quantity < 0: errors.append((product, "Value must be zero or greater.")) - prod = ProductController(product) - limit = prod.user_quantity_remaining(self.cart.user) + limit = with_remainders[product].remainder if quantity > limit: errors.append(( @@ -168,10 +241,13 @@ class CartController(object): for product, quantity in product_quantities: by_cat[product.category].append((product, quantity)) + # Pre-annotate categories + r = CategoryController.attach_user_remainders(self.cart.user, by_cat) + with_remainders = dict((cat, cat) for cat in r) + # Test each category limit here for category in by_cat: - ctrl = CategoryController(category) - limit = ctrl.user_quantity_remaining(self.cart.user) + limit = with_remainders[category].remainder # Get the amount so far in the cart to_add = sum(i[1] for i in by_cat[category]) @@ -185,7 +261,7 @@ class CartController(object): )) # Test the flag conditions - errs = ConditionController.test_flags( + errs = FlagController.test_flags( self.cart.user, product_quantities=product_quantities, ) @@ -212,7 +288,6 @@ class CartController(object): # If successful... self.cart.vouchers.add(voucher) - self.end_batch() def _test_voucher(self, voucher): ''' Tests whether this voucher is allowed to be applied to this cart. @@ -294,6 +369,7 @@ class CartController(object): errors.append(ve) items = commerce.ProductItem.objects.filter(cart=cart) + items = items.select_related("product", "product__category") product_quantities = list((i.product, i.quantity) for i in items) try: @@ -307,19 +383,24 @@ class CartController(object): self._append_errors(errors, ve) # Validate the discounts - discount_items = commerce.DiscountItem.objects.filter(cart=cart) - seen_discounts = set() + # TODO: refactor in terms of available_discounts + # why aren't we doing that here?! + # def available_discounts(cls, user, categories, products): + + products = [i.product for i in items] + discounts_with_quantity = DiscountController.available_discounts( + user, + [], + products, + ) + discounts = set(i.discount.id for i in discounts_with_quantity) + + discount_items = commerce.DiscountItem.objects.filter(cart=cart) for discount_item in discount_items: discount = discount_item.discount - if discount in seen_discounts: - continue - seen_discounts.add(discount) - real_discount = conditions.DiscountBase.objects.get_subclass( - pk=discount.pk) - cond = ConditionController.for_condition(real_discount) - if not cond.is_met(user): + if discount.id not in discounts: errors.append( ValidationError("Discounts are no longer available") ) @@ -328,7 +409,6 @@ class CartController(object): raise ValidationError(errors) @_modifies_cart - @transaction.atomic def fix_simple_errors(self): ''' This attempts to fix the easy errors raised by ValidationError. This includes removing items from the cart that are no longer @@ -360,11 +440,9 @@ class CartController(object): self.set_quantities(zeros) - @_modifies_cart @transaction.atomic - def recalculate_discounts(self): - ''' Calculates all of the discounts available for this product. - ''' + def _recalculate_discounts(self): + ''' Calculates all of the discounts available for this product.''' # Delete the existing entries. commerce.DiscountItem.objects.filter(cart=self.cart).delete() @@ -374,7 +452,11 @@ class CartController(object): ) products = [i.product for i in product_items] - discounts = discount.available_discounts(self.cart.user, [], products) + discounts = DiscountController.available_discounts( + self.cart.user, + [], + products, + ) # The highest-value discounts will apply to the highest-value # products first. diff --git a/registrasion/controllers/category.py b/registrasion/controllers/category.py index a986eea7..9db8ca9e 100644 --- a/registrasion/controllers/category.py +++ b/registrasion/controllers/category.py @@ -1,7 +1,11 @@ from registrasion.models import commerce from registrasion.models import inventory +from django.db.models import Case +from django.db.models import F, Q from django.db.models import Sum +from django.db.models import When +from django.db.models import Value class AllProducts(object): @@ -34,25 +38,47 @@ class CategoryController(object): return set(i.category for i in available) + @classmethod + def attach_user_remainders(cls, user, categories): + ''' + + Return: + queryset(inventory.Product): A queryset containing items from + ``categories``, with an extra attribute -- remainder = the amount + of items from this category that is remaining. + ''' + + ids = [category.id for category in categories] + categories = inventory.Category.objects.filter(id__in=ids) + + cart_filter = ( + Q(product__productitem__cart__user=user) & + Q(product__productitem__cart__status=commerce.Cart.STATUS_PAID) + ) + + quantity = When( + cart_filter, + then='product__productitem__quantity' + ) + + quantity_or_zero = Case( + quantity, + default=Value(0), + ) + + remainder = Case( + When(limit_per_user=None, then=Value(99999999)), + default=F('limit_per_user') - Sum(quantity_or_zero), + ) + + categories = categories.annotate(remainder=remainder) + + return categories + def user_quantity_remaining(self, user): - ''' Returns the number of items from this category that the user may - add in the current cart. ''' + ''' Returns the quantity of this product that the user add in the + current cart. ''' - cat_limit = self.category.limit_per_user + with_remainders = self.attach_user_remainders(user, [self.category]) - if cat_limit is None: - # We don't need to waste the following queries - return 99999999 - - carts = commerce.Cart.objects.filter( - user=user, - status=commerce.Cart.STATUS_PAID, - ) - - items = commerce.ProductItem.objects.filter( - cart__in=carts, - product__category=self.category, - ) - - cat_count = items.aggregate(Sum("quantity"))["quantity__sum"] or 0 - return cat_limit - cat_count + return with_remainders[0].remainder diff --git a/registrasion/controllers/conditions.py b/registrasion/controllers/conditions.py index db40d0c2..51078016 100644 --- a/registrasion/controllers/conditions.py +++ b/registrasion/controllers/conditions.py @@ -1,36 +1,27 @@ -import itertools -import operator - -from collections import defaultdict -from collections import namedtuple - +from django.db.models import Case +from django.db.models import F, Q from django.db.models import Sum +from django.db.models import Value +from django.db.models import When from django.utils import timezone from registrasion.models import commerce from registrasion.models import conditions -from registrasion.models import inventory -ConditionAndRemainder = namedtuple( - "ConditionAndRemainder", - ( - "condition", - "remainder", - ), -) +_BIG_QUANTITY = 99999999 # A big quantity class ConditionController(object): ''' Base class for testing conditions that activate Flag or Discount objects. ''' - def __init__(self): - pass + def __init__(self, condition): + self.condition = condition @staticmethod - def for_condition(condition): - CONTROLLERS = { + def _controllers(): + return { conditions.CategoryFlag: CategoryConditionController, conditions.IncludedProductDiscount: ProductConditionController, conditions.ProductFlag: ProductConditionController, @@ -42,137 +33,49 @@ class ConditionController(object): conditions.VoucherFlag: VoucherConditionController, } + @staticmethod + def for_type(cls): + return ConditionController._controllers()[cls] + + @staticmethod + def for_condition(condition): try: - return CONTROLLERS[type(condition)](condition) + return ConditionController.for_type(type(condition))(condition) except KeyError: return ConditionController() - SINGLE = True - PLURAL = False - NONE = True - SOME = False - MESSAGE = { - NONE: { - SINGLE: - "%(items)s is no longer available to you", - PLURAL: - "%(items)s are no longer available to you", - }, - SOME: { - SINGLE: - "Only %(remainder)d of the following item remains: %(items)s", - PLURAL: - "Only %(remainder)d of the following items remain: %(items)s" - }, - } - @classmethod - def test_flags( - cls, user, products=None, product_quantities=None): - ''' Evaluates all of the flag conditions on the given products. + def pre_filter(cls, queryset, user): + ''' Returns only the flag conditions that might be available for this + user. It should hopefully reduce the number of queries that need to be + executed to determine if a flag is met. - If `product_quantities` is supplied, the condition is only met if it - will permit the sum of the product quantities for all of the products - it covers. Otherwise, it will be met if at least one item can be - accepted. + If this filtration implements the same query as is_met, then you should + be able to implement ``is_met()`` in terms of this. - If all flag conditions pass, an empty list is returned, otherwise - a list is returned containing all of the products that are *not - enabled*. ''' + Arguments: - if products is not None and product_quantities is not None: - raise ValueError("Please specify only products or " - "product_quantities") - elif products is None: - products = set(i[0] for i in product_quantities) - quantities = dict((product, quantity) - for product, quantity in product_quantities) - elif product_quantities is None: - products = set(products) - quantities = {} + queryset (Queryset[c]): The canditate conditions. - # Get the conditions covered by the products themselves - prods = ( - product.flagbase_set.select_subclasses() - for product in products - ) - # Get the conditions covered by their categories - cats = ( - category.flagbase_set.select_subclasses() - for category in set(product.category for product in products) - ) + user (User): The user for whom we're testing these conditions. - if products: - # Simplify the query. - all_conditions = reduce(operator.or_, itertools.chain(prods, cats)) - else: - all_conditions = [] + Returns: + Queryset[c]: A subset of the conditions that pass the pre-filter + test for this user. - # All disable-if-false conditions on a product need to be met - do_not_disable = defaultdict(lambda: True) - # At least one enable-if-true condition on a product must be met - do_enable = defaultdict(lambda: False) - # (if either sort of condition is present) + ''' - messages = {} + # Default implementation does NOTHING. + return queryset - for condition in all_conditions: - cond = cls.for_condition(condition) - remainder = cond.user_quantity_remaining(user) + def passes_filter(self, user): + ''' Returns true if the condition passes the filter ''' - # Get all products covered by this condition, and the products - # from the categories covered by this condition - cond_products = condition.products.all() - from_category = inventory.Product.objects.filter( - category__in=condition.categories.all(), - ).all() - all_products = cond_products | from_category - all_products = all_products.select_related("category") - # Remove the products that we aren't asking about - all_products = [ - product - for product in all_products - if product in products - ] + cls = type(self.condition) + qs = cls.objects.filter(pk=self.condition.id) + return self.condition in self.pre_filter(qs, user) - if quantities: - consumed = sum(quantities[i] for i in all_products) - else: - consumed = 1 - met = consumed <= remainder - - if not met: - items = ", ".join(str(product) for product in all_products) - base = cls.MESSAGE[remainder == 0][len(all_products) == 1] - message = base % {"items": items, "remainder": remainder} - - for product in all_products: - if condition.is_disable_if_false: - do_not_disable[product] &= met - else: - do_enable[product] |= met - - if not met and product not in messages: - messages[product] = message - - valid = {} - for product in itertools.chain(do_not_disable, do_enable): - if product in do_enable: - # If there's an enable-if-true, we need need of those met too. - # (do_not_disable will default to true otherwise) - valid[product] = do_not_disable[product] and do_enable[product] - elif product in do_not_disable: - # If there's a disable-if-false condition, all must be met - valid[product] = do_not_disable[product] - - error_fields = [ - (product, messages[product]) - for product in valid if not valid[product] - ] - - return error_fields - - def user_quantity_remaining(self, user): + def user_quantity_remaining(self, user, filtered=False): ''' Returns the number of items covered by this flag condition the user can add to the current cart. This default implementation returns a big number if is_met() is true, otherwise 0. @@ -180,144 +83,210 @@ class ConditionController(object): Either this method, or is_met() must be overridden in subclasses. ''' - return 99999999 if self.is_met(user) else 0 + return _BIG_QUANTITY if self.is_met(user, filtered) else 0 - def is_met(self, user): + def is_met(self, user, filtered=False): ''' Returns True if this flag condition is met, otherwise returns False. Either this method, or user_quantity_remaining() must be overridden in subclasses. + + Arguments: + + user (User): The user for whom this test must be met. + + filter (bool): If true, this condition was part of a queryset + returned by pre_filter() for this user. + ''' - return self.user_quantity_remaining(user) > 0 + return self.user_quantity_remaining(user, filtered) > 0 -class CategoryConditionController(ConditionController): +class IsMetByFilter(object): - def __init__(self, condition): - self.condition = condition + def is_met(self, user, filtered=False): + ''' Returns True if this flag condition is met, otherwise returns + False. It determines if the condition is met by calling pre_filter + with a queryset containing only self.condition. ''' - def is_met(self, user): - ''' returns True if the user has a product from a category that invokes - this condition in one of their carts ''' + if filtered: + return True # Why query again? - carts = commerce.Cart.objects.filter(user=user) - carts = carts.exclude(status=commerce.Cart.STATUS_RELEASED) - enabling_products = inventory.Product.objects.filter( - category=self.condition.enabling_category, + return self.passes_filter(user) + + +class RemainderSetByFilter(object): + + def user_quantity_remaining(self, user, filtered=True): + ''' returns 0 if the date range is violated, otherwise, it will return + the quantity remaining under the stock limit. + + The filter for this condition must add an annotation called "remainder" + in order for this to work. + ''' + + if filtered: + if hasattr(self.condition, "remainder"): + return self.condition.remainder + + # Mark self.condition with a remainder + qs = type(self.condition).objects.filter(pk=self.condition.id) + qs = self.pre_filter(qs, user) + + if len(qs) > 0: + return qs[0].remainder + else: + return 0 + + +class CategoryConditionController(IsMetByFilter, ConditionController): + + @classmethod + def pre_filter(self, queryset, user): + ''' Returns all of the items from queryset where the user has a + product from a category invoking that item's condition in one of their + carts. ''' + + in_user_carts = Q( + enabling_category__product__productitem__cart__user=user ) - products_count = commerce.ProductItem.objects.filter( - cart__in=carts, - product__in=enabling_products, - ).count() - return products_count > 0 + released = commerce.Cart.STATUS_RELEASED + in_released_carts = Q( + enabling_category__product__productitem__cart__status=released + ) + queryset = queryset.filter(in_user_carts) + queryset = queryset.exclude(in_released_carts) + + return queryset -class ProductConditionController(ConditionController): +class ProductConditionController(IsMetByFilter, ConditionController): ''' Condition tests for ProductFlag and IncludedProductDiscount. ''' - def __init__(self, condition): - self.condition = condition + @classmethod + def pre_filter(self, queryset, user): + ''' Returns all of the items from queryset where the user has a + product invoking that item's condition in one of their carts. ''' - def is_met(self, user): - ''' returns True if the user has a product that invokes this - condition in one of their carts ''' + in_user_carts = Q(enabling_products__productitem__cart__user=user) + released = commerce.Cart.STATUS_RELEASED + in_released_carts = Q( + enabling_products__productitem__cart__status=released + ) + queryset = queryset.filter(in_user_carts) + queryset = queryset.exclude(in_released_carts) - carts = commerce.Cart.objects.filter(user=user) - carts = carts.exclude(status=commerce.Cart.STATUS_RELEASED) - products_count = commerce.ProductItem.objects.filter( - cart__in=carts, - product__in=self.condition.enabling_products.all(), - ).count() - return products_count > 0 + return queryset -class TimeOrStockLimitConditionController(ConditionController): +class TimeOrStockLimitConditionController( + RemainderSetByFilter, + ConditionController, + ): ''' Common condition tests for TimeOrStockLimit Flag and Discount.''' - def __init__(self, ceiling): - self.ceiling = ceiling + @classmethod + def pre_filter(self, queryset, user): + ''' Returns all of the items from queryset where the date falls into + any specified range, but not yet where the stock limit is not yet + reached.''' - def user_quantity_remaining(self, user): - ''' returns 0 if the date range is violated, otherwise, it will return - the quantity remaining under the stock limit. ''' - - # Test date range - if not self._test_date_range(): - return 0 - - return self._get_remaining_stock(user) - - def _test_date_range(self): now = timezone.now() - if self.ceiling.start_time is not None: - if now < self.ceiling.start_time: - return False + # Keep items with no start time, or start time not yet met. + queryset = queryset.filter(Q(start_time=None) | Q(start_time__lte=now)) + queryset = queryset.filter(Q(end_time=None) | Q(end_time__gte=now)) - if self.ceiling.end_time is not None: - if now > self.ceiling.end_time: - return False + # Filter out items that have been reserved beyond the limits + quantity_or_zero = self._calculate_quantities(user) - return True + remainder = Case( + When(limit=None, then=Value(_BIG_QUANTITY)), + default=F("limit") - Sum(quantity_or_zero), + ) - def _get_remaining_stock(self, user): - ''' Returns the stock that remains under this ceiling, excluding the - user's current cart. ''' + queryset = queryset.annotate(remainder=remainder) + queryset = queryset.filter(remainder__gt=0) - if self.ceiling.limit is None: - return 99999999 + return queryset - # We care about all reserved carts, but not the user's current cart + @classmethod + def _relevant_carts(cls, user): reserved_carts = commerce.Cart.reserved_carts() reserved_carts = reserved_carts.exclude( user=user, status=commerce.Cart.STATUS_ACTIVE, ) - - items = self._items() - items = items.filter(cart__in=reserved_carts) - count = items.aggregate(Sum("quantity"))["quantity__sum"] or 0 - - return self.ceiling.limit - count + return reserved_carts class TimeOrStockLimitFlagController( TimeOrStockLimitConditionController): - def _items(self): - category_products = inventory.Product.objects.filter( - category__in=self.ceiling.categories.all(), - ) - products = self.ceiling.products.all() | category_products + @classmethod + def _calculate_quantities(cls, user): + reserved_carts = cls._relevant_carts(user) - product_items = commerce.ProductItem.objects.filter( - product__in=products.all(), + # Calculate category lines + item_cats = F('categories__product__productitem__product__category') + reserved_category_products = ( + Q(categories=item_cats) & + Q(categories__product__productitem__cart__in=reserved_carts) ) - return product_items + + # Calculate product lines + reserved_products = ( + Q(products=F('products__productitem__product')) & + Q(products__productitem__cart__in=reserved_carts) + ) + + category_quantity_in_reserved_carts = When( + reserved_category_products, + then="categories__product__productitem__quantity", + ) + + product_quantity_in_reserved_carts = When( + reserved_products, + then="products__productitem__quantity", + ) + + quantity_or_zero = Case( + category_quantity_in_reserved_carts, + product_quantity_in_reserved_carts, + default=Value(0), + ) + + return quantity_or_zero class TimeOrStockLimitDiscountController(TimeOrStockLimitConditionController): - def _items(self): - discount_items = commerce.DiscountItem.objects.filter( - discount=self.ceiling, + @classmethod + def _calculate_quantities(cls, user): + reserved_carts = cls._relevant_carts(user) + + quantity_in_reserved_carts = When( + discountitem__cart__in=reserved_carts, + then="discountitem__quantity" ) - return discount_items + + quantity_or_zero = Case( + quantity_in_reserved_carts, + default=Value(0) + ) + + return quantity_or_zero -class VoucherConditionController(ConditionController): +class VoucherConditionController(IsMetByFilter, ConditionController): ''' Condition test for VoucherFlag and VoucherDiscount.''' - def __init__(self, condition): - self.condition = condition + @classmethod + def pre_filter(self, queryset, user): + ''' Returns all of the items from queryset where the user has entered + a voucher that invokes that item's condition in one of their carts. ''' - def is_met(self, user): - ''' returns True if the user has the given voucher attached. ''' - carts_count = commerce.Cart.objects.filter( - user=user, - vouchers=self.condition.voucher, - ).count() - return carts_count > 0 + return queryset.filter(voucher__cart__user=user) diff --git a/registrasion/controllers/discount.py b/registrasion/controllers/discount.py index a8f9282e..f4f88ed2 100644 --- a/registrasion/controllers/discount.py +++ b/registrasion/controllers/discount.py @@ -4,7 +4,11 @@ from conditions import ConditionController from registrasion.models import commerce from registrasion.models import conditions +from django.db.models import Case +from django.db.models import F, Q from django.db.models import Sum +from django.db.models import Value +from django.db.models import When class DiscountAndQuantity(object): @@ -38,80 +42,158 @@ class DiscountAndQuantity(object): ) -def available_discounts(user, categories, products): - ''' Returns all discounts available to this user for the given categories - and products. The discounts also list the available quantity for this user, - not including products that are pending purchase. ''' +class DiscountController(object): - # discounts that match provided categories - category_discounts = conditions.DiscountForCategory.objects.filter( - category__in=categories - ) - # discounts that match provided products - product_discounts = conditions.DiscountForProduct.objects.filter( - product__in=products - ) - # discounts that match categories for provided products - product_category_discounts = conditions.DiscountForCategory.objects.filter( - category__in=(product.category for product in products) - ) - # (Not relevant: discounts that match products in provided categories) + @classmethod + def available_discounts(cls, user, categories, products): + ''' Returns all discounts available to this user for the given + categories and products. The discounts also list the available quantity + for this user, not including products that are pending purchase. ''' - product_discounts = product_discounts.select_related( - "product", - "product__category", - ) + filtered_clauses = cls._filtered_discounts(user, categories, products) - all_category_discounts = category_discounts | product_category_discounts - all_category_discounts = all_category_discounts.select_related( - "category", - ) + discounts = [] - # The set of all potential discounts - potential_discounts = set(itertools.chain( - product_discounts, - all_category_discounts, - )) + # Markers so that we don't need to evaluate given conditions + # more than once + accepted_discounts = set() + failed_discounts = set() - discounts = [] + for clause in filtered_clauses: + discount = clause.discount + cond = ConditionController.for_condition(discount) - # Markers so that we don't need to evaluate given conditions more than once - accepted_discounts = set() - failed_discounts = set() + past_use_count = clause.past_use_count + if past_use_count >= clause.quantity: + # This clause has exceeded its use count + pass + elif discount not in failed_discounts: + # This clause is still available + is_accepted = discount in accepted_discounts + if is_accepted or cond.is_met(user, filtered=True): + # This clause is valid for this user + discounts.append(DiscountAndQuantity( + discount=discount, + clause=clause, + quantity=clause.quantity - past_use_count, + )) + accepted_discounts.add(discount) + else: + # This clause is not valid for this user + failed_discounts.add(discount) + return discounts - for discount in potential_discounts: - real_discount = conditions.DiscountBase.objects.get_subclass( - pk=discount.discount.pk, + @classmethod + def _filtered_discounts(cls, user, categories, products): + ''' + + Returns: + Sequence[discountbase]: All discounts that passed the filter + function. + + ''' + + types = list(ConditionController._controllers()) + discounttypes = [ + i for i in types if issubclass(i, conditions.DiscountBase) + ] + + # discounts that match provided categories + category_discounts = conditions.DiscountForCategory.objects.filter( + category__in=categories ) - cond = ConditionController.for_condition(real_discount) - - # Count the past uses of the given discount item. - # If this user has exceeded the limit for the clause, this clause - # is not available any more. - past_uses = commerce.DiscountItem.objects.filter( - cart__user=user, - cart__status=commerce.Cart.STATUS_PAID, # Only past carts count - discount=real_discount, + # discounts that match provided products + product_discounts = conditions.DiscountForProduct.objects.filter( + product__in=products ) - agg = past_uses.aggregate(Sum("quantity")) - past_use_count = agg["quantity__sum"] - if past_use_count is None: - past_use_count = 0 + # discounts that match categories for provided products + product_category_discounts = conditions.DiscountForCategory.objects + product_category_discounts = product_category_discounts.filter( + category__in=(product.category for product in products) + ) + # (Not relevant: discounts that match products in provided categories) - if past_use_count >= discount.quantity: - # This clause has exceeded its use count - pass - elif real_discount not in failed_discounts: - # This clause is still available - if real_discount in accepted_discounts or cond.is_met(user): - # This clause is valid for this user - discounts.append(DiscountAndQuantity( - discount=real_discount, - clause=discount, - quantity=discount.quantity - past_use_count, - )) - accepted_discounts.add(real_discount) - else: - # This clause is not valid for this user - failed_discounts.add(real_discount) - return discounts + product_discounts = product_discounts.select_related( + "product", + "product__category", + ) + + all_category_discounts = ( + category_discounts | product_category_discounts + ) + all_category_discounts = all_category_discounts.select_related( + "category", + ) + + valid_discounts = conditions.DiscountBase.objects.filter( + Q(discountforproduct__in=product_discounts) | + Q(discountforcategory__in=all_category_discounts) + ) + + all_subsets = [] + + for discounttype in discounttypes: + discounts = discounttype.objects.filter(id__in=valid_discounts) + ctrl = ConditionController.for_type(discounttype) + discounts = ctrl.pre_filter(discounts, user) + all_subsets.append(discounts) + + filtered_discounts = list(itertools.chain(*all_subsets)) + + # Map from discount key to itself + # (contains annotations needed in the future) + from_filter = dict((i.id, i) for i in filtered_discounts) + + clause_sets = ( + product_discounts.filter(discount__in=filtered_discounts), + all_category_discounts.filter(discount__in=filtered_discounts), + ) + + clause_sets = ( + cls._annotate_with_past_uses(i, user) for i in clause_sets + ) + + # The set of all potential discount clauses + discount_clauses = set(itertools.chain(*clause_sets)) + + # Replace discounts with the filtered ones + # These are the correct subclasses (saves query later on), and have + # correct annotations from filters if necessary. + for clause in discount_clauses: + clause.discount = from_filter[clause.discount.id] + + return discount_clauses + + @classmethod + def _annotate_with_past_uses(cls, queryset, user): + ''' Annotates the queryset with a usage count for that discount claus + by the given user. ''' + + if queryset.model == conditions.DiscountForCategory: + matches = ( + Q(category=F('discount__discountitem__product__category')) + ) + elif queryset.model == conditions.DiscountForProduct: + matches = ( + Q(product=F('discount__discountitem__product')) + ) + + in_carts = ( + Q(discount__discountitem__cart__user=user) & + Q(discount__discountitem__cart__status=commerce.Cart.STATUS_PAID) + ) + + past_use_quantity = When( + in_carts & matches, + then="discount__discountitem__quantity", + ) + + past_use_quantity_or_zero = Case( + past_use_quantity, + default=Value(0), + ) + + queryset = queryset.annotate( + past_use_count=Sum(past_use_quantity_or_zero) + ) + return queryset diff --git a/registrasion/controllers/flag.py b/registrasion/controllers/flag.py new file mode 100644 index 00000000..aa11d53e --- /dev/null +++ b/registrasion/controllers/flag.py @@ -0,0 +1,264 @@ +import itertools +import operator + +from collections import defaultdict +from collections import namedtuple +from django.db.models import Count +from django.db.models import Q + +from .conditions import ConditionController + +from registrasion.models import conditions +from registrasion.models import inventory + + +class FlagController(object): + + SINGLE = True + PLURAL = False + NONE = True + SOME = False + MESSAGE = { + NONE: { + SINGLE: + "%(items)s is no longer available to you", + PLURAL: + "%(items)s are no longer available to you", + }, + SOME: { + SINGLE: + "Only %(remainder)d of the following item remains: %(items)s", + PLURAL: + "Only %(remainder)d of the following items remain: %(items)s" + }, + } + + @classmethod + def test_flags( + cls, user, products=None, product_quantities=None): + ''' Evaluates all of the flag conditions on the given products. + + If `product_quantities` is supplied, the condition is only met if it + will permit the sum of the product quantities for all of the products + it covers. Otherwise, it will be met if at least one item can be + accepted. + + If all flag conditions pass, an empty list is returned, otherwise + a list is returned containing all of the products that are *not + enabled*. ''' + + print "GREPME: test_flags()" + + if products is not None and product_quantities is not None: + raise ValueError("Please specify only products or " + "product_quantities") + elif products is None: + products = set(i[0] for i in product_quantities) + quantities = dict((product, quantity) + for product, quantity in product_quantities) + elif product_quantities is None: + products = set(products) + quantities = {} + + if products: + # Simplify the query. + all_conditions = cls._filtered_flags(user, products) + else: + all_conditions = [] + + # All disable-if-false conditions on a product need to be met + do_not_disable = defaultdict(lambda: True) + # At least one enable-if-true condition on a product must be met + do_enable = defaultdict(lambda: False) + # (if either sort of condition is present) + + # Count the number of conditions for a product + dif_count = defaultdict(int) + eit_count = defaultdict(int) + + messages = {} + + for condition in all_conditions: + cond = ConditionController.for_condition(condition) + remainder = cond.user_quantity_remaining(user, filtered=True) + + # Get all products covered by this condition, and the products + # from the categories covered by this condition + + ids = [product.id for product in products] + all_products = inventory.Product.objects.filter(id__in=ids) + cond = ( + Q(flagbase_set=condition) | + Q(category__in=condition.categories.all()) + ) + + all_products = all_products.filter(cond) + all_products = all_products.select_related("category") + + if quantities: + consumed = sum(quantities[i] for i in all_products) + else: + consumed = 1 + met = consumed <= remainder + + if not met: + items = ", ".join(str(product) for product in all_products) + base = cls.MESSAGE[remainder == 0][len(all_products) == 1] + message = base % {"items": items, "remainder": remainder} + + for product in all_products: + if condition.is_disable_if_false: + do_not_disable[product] &= met + dif_count[product] += 1 + else: + do_enable[product] |= met + eit_count[product] += 1 + + if not met and product not in messages: + messages[product] = message + + total_flags = FlagCounter.count() + + valid = {} + + # the problem is that now, not every condition falls into + # do_not_disable or do_enable ''' + # You should look into this, chris :) + + for product in products: + if quantities: + if quantities[product] == 0: + continue + + f = total_flags.get(product) + if f.dif > 0 and f.dif != dif_count[product]: + do_not_disable[product] = False + if product not in messages: + messages[product] = "Some disable-if-false " \ + "conditions were not met" + if f.eit > 0 and product not in do_enable: + do_enable[product] = False + if product not in messages: + messages[product] = "Some enable-if-true " \ + "conditions were not met" + + for product in itertools.chain(do_not_disable, do_enable): + f = total_flags.get(product) + if product in do_enable: + # If there's an enable-if-true, we need need of those met too. + # (do_not_disable will default to true otherwise) + valid[product] = do_not_disable[product] and do_enable[product] + elif product in do_not_disable: + # If there's a disable-if-false condition, all must be met + valid[product] = do_not_disable[product] + + error_fields = [ + (product, messages[product]) + for product in valid if not valid[product] + ] + + return error_fields + + @classmethod + def _filtered_flags(cls, user, products): + ''' + + Returns: + Sequence[flagbase]: All flags that passed the filter function. + + ''' + + types = list(ConditionController._controllers()) + flagtypes = [i for i in types if issubclass(i, conditions.FlagBase)] + + # Get all flags for the products and categories. + prods = ( + product.flagbase_set.all() + for product in products + ) + cats = ( + category.flagbase_set.all() + for category in set(product.category for product in products) + ) + all_flags = reduce(operator.or_, itertools.chain(prods, cats)) + + all_subsets = [] + + for flagtype in flagtypes: + flags = flagtype.objects.filter(id__in=all_flags) + ctrl = ConditionController.for_type(flagtype) + flags = ctrl.pre_filter(flags, user) + all_subsets.append(flags) + + return itertools.chain(*all_subsets) + + +ConditionAndRemainder = namedtuple( + "ConditionAndRemainder", + ( + "condition", + "remainder", + ), +) + + +_FlagCounter = namedtuple( + "_FlagCounter", + ( + "products", + "categories", + ), +) + + +_ConditionsCount = namedtuple( + "ConditionsCount", + ( + "dif", + "eit", + ), +) + + +# TODO: this should be cacheable. +class FlagCounter(_FlagCounter): + + @classmethod + def count(cls): + # Get the count of how many conditions should exist per product + flagbases = conditions.FlagBase.objects + + types = ( + conditions.FlagBase.ENABLE_IF_TRUE, + conditions.FlagBase.DISABLE_IF_FALSE, + ) + keys = ("eit", "dif") + flags = [ + flagbases.filter( + condition=condition_type + ).values( + 'products', 'categories' + ).annotate( + count=Count('id') + ) + for condition_type in types + ] + + cats = defaultdict(lambda: defaultdict(int)) + prod = defaultdict(lambda: defaultdict(int)) + + for key, flagcounts in zip(keys, flags): + for row in flagcounts: + if row["products"] is not None: + prod[row["products"]][key] = row["count"] + if row["categories"] is not None: + cats[row["categories"]][key] = row["count"] + + return cls(products=prod, categories=cats) + + def get(self, product): + p = self.products[product.id] + c = self.categories[product.category.id] + eit = p["eit"] + c["eit"] + dif = p["dif"] + c["dif"] + return _ConditionsCount(dif=dif, eit=eit) diff --git a/registrasion/controllers/invoice.py b/registrasion/controllers/invoice.py index 62bab0b6..da737a73 100644 --- a/registrasion/controllers/invoice.py +++ b/registrasion/controllers/invoice.py @@ -29,6 +29,7 @@ class InvoiceController(ForId, object): If such an invoice does not exist, the cart is validated, and if valid, an invoice is generated.''' + cart.refresh_from_db() try: invoice = commerce.Invoice.objects.exclude( status=commerce.Invoice.STATUS_VOID, @@ -74,6 +75,8 @@ class InvoiceController(ForId, object): def _generate(cls, cart): ''' Generates an invoice for the given cart. ''' + cart.refresh_from_db() + issued = timezone.now() reservation_limit = cart.reservation_duration + cart.time_last_updated # Never generate a due time that is before the issue time @@ -96,6 +99,10 @@ class InvoiceController(ForId, object): ) product_items = commerce.ProductItem.objects.filter(cart=cart) + product_items = product_items.select_related( + "product", + "product__category", + ) if len(product_items) == 0: raise ValidationError("Your cart is empty.") @@ -103,29 +110,41 @@ class InvoiceController(ForId, object): product_items = product_items.order_by( "product__category__order", "product__order" ) + discount_items = commerce.DiscountItem.objects.filter(cart=cart) + discount_items = discount_items.select_related( + "discount", + "product", + "product__category", + ) + + line_items = [] + invoice_value = Decimal() for item in product_items: product = item.product - line_item = commerce.LineItem.objects.create( + line_item = commerce.LineItem( invoice=invoice, description="%s - %s" % (product.category.name, product.name), quantity=item.quantity, price=product.price, product=product, ) + line_items.append(line_item) invoice_value += line_item.quantity * line_item.price - for item in discount_items: - line_item = commerce.LineItem.objects.create( + line_item = commerce.LineItem( invoice=invoice, description=item.discount.description, quantity=item.quantity, price=cls.resolve_discount_value(item) * -1, product=item.product, ) + line_items.append(line_item) invoice_value += line_item.quantity * line_item.price + commerce.LineItem.objects.bulk_create(line_items) + invoice.value = invoice_value invoice.save() @@ -251,6 +270,9 @@ class InvoiceController(ForId, object): def _invoice_matches_cart(self): ''' Returns true if there is no cart, or if the revision of this invoice matches the current revision of the cart. ''' + + self._refresh() + cart = self.invoice.cart if not cart: return True diff --git a/registrasion/controllers/product.py b/registrasion/controllers/product.py index 99618ded..610c7f0d 100644 --- a/registrasion/controllers/product.py +++ b/registrasion/controllers/product.py @@ -1,11 +1,16 @@ import itertools +from django.db.models import Case +from django.db.models import F, Q from django.db.models import Sum +from django.db.models import When +from django.db.models import Value + from registrasion.models import commerce from registrasion.models import inventory -from category import CategoryController -from conditions import ConditionController +from .category import CategoryController +from .flag import FlagController class ProductController(object): @@ -16,9 +21,7 @@ class ProductController(object): @classmethod def available_products(cls, user, category=None, products=None): ''' Returns a list of all of the products that are available per - flag conditions from the given categories. - TODO: refactor so that all conditions are tested here and - can_add_with_flags calls this method. ''' + flag conditions from the given categories. ''' if category is None and products is None: raise ValueError("You must provide products or a category") @@ -31,22 +34,21 @@ class ProductController(object): if products is not None: all_products = set(itertools.chain(all_products, products)) - cat_quants = dict( - ( - category, - CategoryController(category).user_quantity_remaining(user), - ) - for category in set(product.category for product in all_products) - ) + categories = set(product.category for product in all_products) + r = CategoryController.attach_user_remainders(user, categories) + cat_quants = dict((c, c) for c in r) + + r = ProductController.attach_user_remainders(user, all_products) + prod_quants = dict((p, p) for p in r) passed_limits = set( product for product in all_products - if cat_quants[product.category] > 0 - if cls(product).user_quantity_remaining(user) > 0 + if cat_quants[product.category].remainder > 0 + if prod_quants[product].remainder > 0 ) - failed_and_messages = ConditionController.test_flags( + failed_and_messages = FlagController.test_flags( user, products=passed_limits ) failed_conditions = set(i[0] for i in failed_and_messages) @@ -56,26 +58,47 @@ class ProductController(object): return out + @classmethod + def attach_user_remainders(cls, user, products): + ''' + + Return: + queryset(inventory.Product): A queryset containing items from + ``product``, with an extra attribute -- remainder = the amount of + this item that is remaining. + ''' + + ids = [product.id for product in products] + products = inventory.Product.objects.filter(id__in=ids) + + cart_filter = ( + Q(productitem__cart__user=user) & + Q(productitem__cart__status=commerce.Cart.STATUS_PAID) + ) + + quantity = When( + cart_filter, + then='productitem__quantity' + ) + + quantity_or_zero = Case( + quantity, + default=Value(0), + ) + + remainder = Case( + When(limit_per_user=None, then=Value(99999999)), + default=F('limit_per_user') - Sum(quantity_or_zero), + ) + + products = products.annotate(remainder=remainder) + + return products + def user_quantity_remaining(self, user): ''' Returns the quantity of this product that the user add in the current cart. ''' - prod_limit = self.product.limit_per_user + with_remainders = self.attach_user_remainders(user, [self.product]) - if prod_limit is None: - # Don't need to run the remaining queries - return 999999 # We can do better - - carts = commerce.Cart.objects.filter( - user=user, - status=commerce.Cart.STATUS_PAID, - ) - - items = commerce.ProductItem.objects.filter( - cart__in=carts, - product=self.product, - ) - - prod_count = items.aggregate(Sum("quantity"))["quantity__sum"] or 0 - - return prod_limit - prod_count + return with_remainders[0].remainder diff --git a/registrasion/templatetags/registrasion_tags.py b/registrasion/templatetags/registrasion_tags.py index fabc7754..9074781c 100644 --- a/registrasion/templatetags/registrasion_tags.py +++ b/registrasion/templatetags/registrasion_tags.py @@ -4,7 +4,11 @@ from registrasion.controllers.category import CategoryController from collections import namedtuple from django import template +from django.db.models import Case +from django.db.models import Q from django.db.models import Sum +from django.db.models import When +from django.db.models import Value register = template.Library() @@ -99,20 +103,33 @@ def items_purchased(context, category=None): ''' - all_items = commerce.ProductItem.objects.filter( - cart__user=context.request.user, - cart__status=commerce.Cart.STATUS_PAID, - ).select_related("product", "product__category") + in_cart = ( + Q(productitem__cart__user=context.request.user) & + Q(productitem__cart__status=commerce.Cart.STATUS_PAID) + ) + + quantities_in_cart = When( + in_cart, + then="productitem__quantity", + ) + + quantities_or_zero = Case( + quantities_in_cart, + default=Value(0), + ) + + products = inventory.Product.objects if category: - all_items = all_items.filter(product__category=category) + products = products.filter(category=category) + + products = products.select_related("category") + products = products.annotate(quantity=Sum(quantities_or_zero)) + products = products.filter(quantity__gt=0) - pq = all_items.values("product").annotate(quantity=Sum("quantity")).all() - products = inventory.Product.objects.all() out = [] - for item in pq: - prod = products.get(pk=item["product"]) - out.append(ProductAndQuantity(prod, item["quantity"])) + for prod in products: + out.append(ProductAndQuantity(prod, prod.quantity)) return out diff --git a/registrasion/tests/test_cart.py b/registrasion/tests/test_cart.py index 507d5cf7..790c1df9 100644 --- a/registrasion/tests/test_cart.py +++ b/registrasion/tests/test_cart.py @@ -26,7 +26,7 @@ class RegistrationCartTestCase(SetTimeMixin, TestCase): super(RegistrationCartTestCase, self).setUp() def tearDown(self): - if False: + if True: # If you're seeing segfaults in tests, enable this. call_command( 'flush', diff --git a/registrasion/tests/test_ceilings.py b/registrasion/tests/test_ceilings.py index 877556d0..87b54946 100644 --- a/registrasion/tests/test_ceilings.py +++ b/registrasion/tests/test_ceilings.py @@ -6,6 +6,8 @@ from django.core.exceptions import ValidationError from controller_helpers import TestingCartController from test_cart import RegistrationCartTestCase +from registrasion.controllers.discount import DiscountController +from registrasion.controllers.product import ProductController from registrasion.models import commerce from registrasion.models import conditions @@ -135,6 +137,43 @@ class CeilingsTestCases(RegistrationCartTestCase): with self.assertRaises(ValidationError): first_cart.validate_cart() + def test_discount_ceiling_aggregates_products(self): + # Create two carts, add 1xprod_1 to each. Ceiling should disappear + # after second. + self.make_discount_ceiling( + "Multi-product limit discount ceiling", + limit=2, + ) + for i in xrange(2): + cart = TestingCartController.for_user(self.USER_1) + cart.add_to_cart(self.PROD_1, 1) + cart.next_cart() + + discounts = DiscountController.available_discounts( + self.USER_1, + [], + [self.PROD_1], + ) + + self.assertEqual(0, len(discounts)) + + def test_flag_ceiling_aggregates_products(self): + # Create two carts, add 1xprod_1 to each. Ceiling should disappear + # after second. + self.make_ceiling("Multi-product limit ceiling", limit=2) + + for i in xrange(2): + cart = TestingCartController.for_user(self.USER_1) + cart.add_to_cart(self.PROD_1, 1) + cart.next_cart() + + products = ProductController.available_products( + self.USER_1, + products=[self.PROD_1], + ) + + self.assertEqual(0, len(products)) + def test_items_released_from_ceiling_by_refund(self): self.make_ceiling("Limit ceiling", limit=1) diff --git a/registrasion/tests/test_discount.py b/registrasion/tests/test_discount.py index 71d09d97..d7920a10 100644 --- a/registrasion/tests/test_discount.py +++ b/registrasion/tests/test_discount.py @@ -4,7 +4,7 @@ from decimal import Decimal from registrasion.models import commerce from registrasion.models import conditions -from registrasion.controllers import discount +from registrasion.controllers.discount import DiscountController from controller_helpers import TestingCartController from test_cart import RegistrationCartTestCase @@ -243,22 +243,30 @@ class DiscountTestCase(RegistrationCartTestCase): # The discount is applied. self.assertEqual(1, len(discount_items)) - # Tests for the discount.available_discounts enumerator + # Tests for the DiscountController.available_discounts enumerator def test_enumerate_no_discounts_for_no_input(self): - discounts = discount.available_discounts(self.USER_1, [], []) + discounts = DiscountController.available_discounts( + self.USER_1, + [], + [], + ) self.assertEqual(0, len(discounts)) def test_enumerate_no_discounts_if_condition_not_met(self): self.add_discount_prod_1_includes_cat_2(quantity=1) - discounts = discount.available_discounts( + discounts = DiscountController.available_discounts( self.USER_1, [], [self.PROD_3], ) self.assertEqual(0, len(discounts)) - discounts = discount.available_discounts(self.USER_1, [self.CAT_2], []) + discounts = DiscountController.available_discounts( + self.USER_1, + [self.CAT_2], + [], + ) self.assertEqual(0, len(discounts)) def test_category_discount_appears_once_if_met_twice(self): @@ -267,7 +275,7 @@ class DiscountTestCase(RegistrationCartTestCase): cart = TestingCartController.for_user(self.USER_1) cart.add_to_cart(self.PROD_1, 1) # Enable the discount - discounts = discount.available_discounts( + discounts = DiscountController.available_discounts( self.USER_1, [self.CAT_2], [self.PROD_3], @@ -280,7 +288,11 @@ class DiscountTestCase(RegistrationCartTestCase): cart = TestingCartController.for_user(self.USER_1) cart.add_to_cart(self.PROD_1, 1) # Enable the discount - discounts = discount.available_discounts(self.USER_1, [self.CAT_2], []) + discounts = DiscountController.available_discounts( + self.USER_1, + [self.CAT_2], + [], + ) self.assertEqual(1, len(discounts)) def test_category_discount_appears_with_product(self): @@ -289,7 +301,7 @@ class DiscountTestCase(RegistrationCartTestCase): cart = TestingCartController.for_user(self.USER_1) cart.add_to_cart(self.PROD_1, 1) # Enable the discount - discounts = discount.available_discounts( + discounts = DiscountController.available_discounts( self.USER_1, [], [self.PROD_3], @@ -302,7 +314,7 @@ class DiscountTestCase(RegistrationCartTestCase): cart = TestingCartController.for_user(self.USER_1) cart.add_to_cart(self.PROD_1, 1) # Enable the discount - discounts = discount.available_discounts( + discounts = DiscountController.available_discounts( self.USER_1, [], [self.PROD_3, self.PROD_4] @@ -315,7 +327,7 @@ class DiscountTestCase(RegistrationCartTestCase): cart = TestingCartController.for_user(self.USER_1) cart.add_to_cart(self.PROD_1, 1) # Enable the discount - discounts = discount.available_discounts( + discounts = DiscountController.available_discounts( self.USER_1, [], [self.PROD_2], @@ -328,7 +340,11 @@ class DiscountTestCase(RegistrationCartTestCase): cart = TestingCartController.for_user(self.USER_1) cart.add_to_cart(self.PROD_1, 1) # Enable the discount - discounts = discount.available_discounts(self.USER_1, [self.CAT_1], []) + discounts = DiscountController.available_discounts( + self.USER_1, + [self.CAT_1], + [], + ) self.assertEqual(0, len(discounts)) def test_discount_quantity_is_correct_before_first_purchase(self): @@ -338,7 +354,11 @@ class DiscountTestCase(RegistrationCartTestCase): cart.add_to_cart(self.PROD_1, 1) # Enable the discount cart.add_to_cart(self.PROD_3, 1) # Exhaust the quantity - discounts = discount.available_discounts(self.USER_1, [self.CAT_2], []) + discounts = DiscountController.available_discounts( + self.USER_1, + [self.CAT_2], + [], + ) self.assertEqual(2, discounts[0].quantity) cart.next_cart() @@ -349,32 +369,63 @@ class DiscountTestCase(RegistrationCartTestCase): cart = TestingCartController.for_user(self.USER_1) cart.add_to_cart(self.PROD_3, 1) # Exhaust the quantity - discounts = discount.available_discounts(self.USER_1, [self.CAT_2], []) + discounts = DiscountController.available_discounts( + self.USER_1, + [self.CAT_2], + [], + ) self.assertEqual(1, discounts[0].quantity) cart.next_cart() def test_discount_is_gone_after_quantity_exhausted(self): self.test_discount_quantity_is_correct_after_first_purchase() - discounts = discount.available_discounts(self.USER_1, [self.CAT_2], []) + discounts = DiscountController.available_discounts( + self.USER_1, + [self.CAT_2], + [], + ) self.assertEqual(0, len(discounts)) def test_product_discount_enabled_twice_appears_twice(self): self.add_discount_prod_1_includes_prod_3_and_prod_4(quantity=2) cart = TestingCartController.for_user(self.USER_1) cart.add_to_cart(self.PROD_1, 1) # Enable the discount - discounts = discount.available_discounts( + discounts = DiscountController.available_discounts( self.USER_1, [], [self.PROD_3, self.PROD_4], ) self.assertEqual(2, len(discounts)) + def test_product_discount_applied_on_different_invoices(self): + # quantity=1 means "quantity per product" + self.add_discount_prod_1_includes_prod_3_and_prod_4(quantity=1) + cart = TestingCartController.for_user(self.USER_1) + cart.add_to_cart(self.PROD_1, 1) # Enable the discount + discounts = DiscountController.available_discounts( + self.USER_1, + [], + [self.PROD_3, self.PROD_4], + ) + self.assertEqual(2, len(discounts)) + # adding one of PROD_3 should make it no longer an available discount. + cart.add_to_cart(self.PROD_3, 1) + cart.next_cart() + + # should still have (and only have) the discount for prod_4 + discounts = DiscountController.available_discounts( + self.USER_1, + [], + [self.PROD_3, self.PROD_4], + ) + self.assertEqual(1, len(discounts)) + def test_discounts_are_released_by_refunds(self): self.add_discount_prod_1_includes_prod_2(quantity=2) cart = TestingCartController.for_user(self.USER_1) cart.add_to_cart(self.PROD_1, 1) # Enable the discount - discounts = discount.available_discounts( + discounts = DiscountController.available_discounts( self.USER_1, [], [self.PROD_2], @@ -388,7 +439,7 @@ class DiscountTestCase(RegistrationCartTestCase): cart.next_cart() - discounts = discount.available_discounts( + discounts = DiscountController.available_discounts( self.USER_1, [], [self.PROD_2], @@ -398,7 +449,7 @@ class DiscountTestCase(RegistrationCartTestCase): cart.cart.status = commerce.Cart.STATUS_RELEASED cart.cart.save() - discounts = discount.available_discounts( + discounts = DiscountController.available_discounts( self.USER_1, [], [self.PROD_2], diff --git a/registrasion/util.py b/registrasion/util.py index 7179ceb5..54f56a1e 100644 --- a/registrasion/util.py +++ b/registrasion/util.py @@ -25,3 +25,33 @@ def all_arguments_optional(ntcls): ) return ntcls + + +def lazy(function, *args, **kwargs): + ''' Produces a callable so that functions can be lazily evaluated in + templates. + + Arguments: + + function (callable): The function to call at evaluation time. + + args: Positional arguments, passed directly to ``function``. + + kwargs: Keyword arguments, passed directly to ``function``. + + Return: + + callable: A callable that will evaluate a call to ``function`` with + the specified arguments. + + ''' + + NOT_EVALUATED = object() + retval = [NOT_EVALUATED] + + def evaluate(): + if retval[0] is NOT_EVALUATED: + retval[0] = function(*args, **kwargs) + return retval[0] + + return evaluate diff --git a/registrasion/views.py b/registrasion/views.py index f10de90f..a4dcceac 100644 --- a/registrasion/views.py +++ b/registrasion/views.py @@ -5,7 +5,7 @@ from registrasion import util from registrasion.models import commerce from registrasion.models import inventory from registrasion.models import people -from registrasion.controllers import discount +from registrasion.controllers.discount import DiscountController from registrasion.controllers.cart import CartController from registrasion.controllers.credit_note import CreditNoteController from registrasion.controllers.invoice import InvoiceController @@ -181,33 +181,35 @@ def guided_registration(request): attendee.save() return next_step - for category in cats: - products = [ - i for i in available_products - if i.category == category - ] + with CartController.operations_batch(request.user): + for category in cats: + products = [ + i for i in available_products + if i.category == category + ] - prefix = "category_" + str(category.id) - p = _handle_products(request, category, products, prefix) - products_form, discounts, products_handled = p + prefix = "category_" + str(category.id) + p = _handle_products(request, category, products, prefix) + products_form, discounts, products_handled = p - section = GuidedRegistrationSection( - title=category.name, - description=category.description, - discounts=discounts, - form=products_form, - ) + section = GuidedRegistrationSection( + title=category.name, + description=category.description, + discounts=discounts, + form=products_form, + ) - if products: - # This product category has items to show. - sections.append(section) - # Add this to the list of things to show if the form errors. - request.session[SESSION_KEY].append(category.id) + if products: + # This product category has items to show. + sections.append(section) + # Add this to the list of things to show if the form + # errors. + request.session[SESSION_KEY].append(category.id) - if request.method == "POST" and not products_form.errors: - # This is only saved if we pass each form with no errors, - # and if the form actually has products. - attendee.guided_categories_complete.add(category) + if request.method == "POST" and not products_form.errors: + # This is only saved if we pass each form with no + # errors, and if the form actually has products. + attendee.guided_categories_complete.add(category) if sections and request.method == "POST": for section in sections: @@ -427,7 +429,15 @@ def _handle_products(request, category, products, prefix): ) handled = False if products_form.errors else True - discounts = discount.available_discounts(request.user, [], products) + # Making this a function to lazily evaluate when it's displayed + # in templates. + + discounts = util.lazy( + DiscountController.available_discounts, + request.user, + [], + products, + ) return products_form, discounts, handled @@ -435,14 +445,14 @@ def _handle_products(request, category, products, prefix): def _set_quantities_from_products_form(products_form, current_cart): quantities = list(products_form.product_quantities()) - + id_to_quantity = dict(i[:2] for i in quantities) pks = [i[0] for i in quantities] products = inventory.Product.objects.filter( id__in=pks, ).select_related("category") product_quantities = [ - (products.get(pk=i[0]), i[1]) for i in quantities + (product, id_to_quantity[product.id]) for product in products ] field_names = dict( (i[0][0], i[1][2]) for i in zip(product_quantities, quantities) diff --git a/setup.cfg b/setup.cfg index 290fdb45..9b05640c 100644 --- a/setup.cfg +++ b/setup.cfg @@ -1,2 +1,2 @@ [flake8] -exclude = registrasion/migrations/*, build/*, docs/* +exclude = registrasion/migrations/*, build/*, docs/*, dist/*