Files
pretix_original/src/pretix/api/views/cart.py
2025-12-17 17:09:06 +01:00

258 lines
11 KiB
Python

#
# This file is part of pretix (Community Edition).
#
# Copyright (C) 2014-2020 Raphael Michel and contributors
# Copyright (C) 2020-today pretix GmbH and contributors
#
# This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General
# Public License as published by the Free Software Foundation in version 3 of the License.
#
# ADDITIONAL TERMS APPLY: Pursuant to Section 7 of the GNU Affero General Public License, additional terms are
# applicable granting you additional permissions and placing additional restrictions on your usage of this software.
# Please refer to the pretix LICENSE file to obtain the full terms applicable to this work. If you did not receive
# this file, see <https://pretix.eu/about/en/license>.
#
# This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
# warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
# details.
#
# You should have received a copy of the GNU Affero General Public License along with this program. If not, see
# <https://www.gnu.org/licenses/>.
#
from collections import Counter
from typing import List
from django.db import transaction
from django.utils.crypto import get_random_string
from django.utils.functional import cached_property
from django.utils.timezone import now
from django.utils.translation import gettext as _
from rest_framework import status, viewsets
from rest_framework.decorators import action
from rest_framework.exceptions import ValidationError
from rest_framework.mixins import CreateModelMixin, DestroyModelMixin
from rest_framework.response import Response
from rest_framework.serializers import as_serializer_error
from pretix.api.pagination import TotalOrderingFilter
from pretix.api.serializers.cart import (
CartPositionCreateSerializer, CartPositionSerializer,
)
from pretix.base.models import CartPosition
from pretix.base.services.cart import (
_get_quota_availability, _get_voucher_availability, error_messages,
)
from pretix.base.services.locking import lock_objects
class CartPositionViewSet(CreateModelMixin, DestroyModelMixin, viewsets.ReadOnlyModelViewSet):
serializer_class = CartPositionSerializer
queryset = CartPosition.objects.none()
filter_backends = (TotalOrderingFilter,)
ordering = ('datetime',)
ordering_fields = ('datetime', 'cart_id')
lookup_field = 'id'
permission = 'event.orders:read'
write_permission = 'event.orders:write'
def get_queryset(self):
return CartPosition.objects.filter(
event=self.request.event,
cart_id__endswith="@api"
).select_related('seat').prefetch_related('answers')
def get_serializer_context(self):
ctx = super().get_serializer_context()
ctx['event'] = self.request.event
ctx['quotas_for_item_cache'] = {}
ctx['quotas_for_variation_cache'] = {}
return ctx
def create(self, request, *args, **kwargs):
ctx = self.get_serializer_context()
serializer = CartPositionCreateSerializer(data=request.data, context=ctx)
serializer.is_valid(raise_exception=True)
results = self._create(serializers=[serializer], raise_exception=True, ctx=ctx)
headers = self.get_success_headers(serializer.data)
return Response(results[0]['data'], status=status.HTTP_201_CREATED, headers=headers)
@action(detail=False, methods=['POST'])
def bulk_create(self, request, *args, **kwargs):
if not isinstance(request.data, list): # noqa
return Response({"error": "Please supply a list"}, status=status.HTTP_400_BAD_REQUEST)
ctx = self.get_serializer_context()
serializers = [
CartPositionCreateSerializer(data=d, context=ctx)
for d in request.data
]
results = self._create(serializers=serializers, raise_exception=False, ctx=ctx)
return Response({'results': results}, status=status.HTTP_200_OK)
def perform_create(self, serializer):
raise NotImplementedError()
@transaction.atomic()
def perform_destroy(self, instance):
instance.addons.all().delete()
instance.delete()
def _require_locking(self, quota_diff, voucher_use_diff, seat_diff):
if voucher_use_diff or seat_diff:
# If any vouchers or seats are used, we lock to make sure we don't redeem them to often
return True
if quota_diff and any(q.size is not None for q in quota_diff):
# If any quotas are affected that are not unlimited, we lock
return True
return False
@cached_property
def _create_default_cart_id(self):
cid = "{}@api".format(get_random_string(48))
while CartPosition.objects.filter(cart_id=cid).exists():
cid = "{}@api".format(get_random_string(48))
return cid
def _create(self, serializers: List[CartPositionCreateSerializer], ctx, raise_exception=False):
voucher_use_diff = Counter()
quota_diff = Counter()
seat_diff = Counter()
results = [{} for pserializer in serializers]
for i, pserializer in enumerate(serializers):
if not pserializer.is_valid(raise_exception=raise_exception):
results[i] = {
'success': False,
'data': None,
'errors': pserializer.errors,
}
for pserializer in serializers:
if pserializer.errors:
continue
validated_data = pserializer.validated_data
if not validated_data.get('cart_id'):
validated_data['cart_id'] = self._create_default_cart_id
if validated_data.get('voucher'):
voucher_use_diff[validated_data['voucher']] += 1
if validated_data.get('seat'):
seat_diff[validated_data['seat']] += 1
for q in validated_data['_quotas']:
quota_diff[q] += 1
for sub_data in validated_data.get('addons', []) + validated_data.get('bundled', []):
for q in sub_data['_quotas']:
quota_diff[q] += 1
seats_seen = set()
now_dt = now()
with transaction.atomic():
full_lock_required = seat_diff and self.request.event.settings.seating_minimal_distance > 0
if full_lock_required:
# We lock the entire event in this case since we don't want to deal with fine-granular locking
# in the case of seating distance enforcement
lock_objects([self.request.event])
else:
lock_objects(
[q for q, d in quota_diff.items() if q.size is not None and d > 0] +
[v for v, d in voucher_use_diff.items() if d > 0] +
[s for s, d in seat_diff.items() if d > 0],
shared_lock_objects=[self.request.event]
)
vouchers_ok, vouchers_depend_on_cart = _get_voucher_availability(
self.request.event,
voucher_use_diff,
now_dt,
exclude_position_ids=[],
)
quotas_ok = _get_quota_availability(quota_diff, now_dt)
for i, pserializer in enumerate(serializers):
if results[i]:
continue
try:
validated_data = pserializer.validated_data
if validated_data.get('seat'):
# Assumption: Add-ons currently can't have seats
if validated_data['seat'] in seats_seen:
raise ValidationError(error_messages['seat_multiple'])
seats_seen.add(validated_data['seat'])
quotas_needed = Counter()
for q in validated_data['_quotas']:
quotas_needed[q] += 1
for sub_data in validated_data.get('addons', []) + validated_data.get('bundled', []):
for q in sub_data['_quotas']:
quotas_needed[q] += 1
for q, needed in quotas_needed.items():
if quotas_ok[q] < needed:
raise ValidationError(
_('There is not enough quota available on quota "{}" to perform the operation.').format(
q.name
)
)
if validated_data.get('voucher'):
# Assumption: Add-ons currently can't have vouchers, thus we only need to check the main voucher
if vouchers_ok[validated_data['voucher']] < 1:
raise ValidationError(
{'voucher': [_('The specified voucher has already been used the maximum number of times.')]}
)
if validated_data.get('seat'):
# Assumption: Add-ons currently can't have seats, thus we only need to check the main product
if validated_data.get('sales_channel'):
sales_channel_id = validated_data.get('sales_channel').identifier
else:
sales_channel_id = "web"
if not validated_data['seat'].is_available(
sales_channel=sales_channel_id,
distance_ignore_cart_id=validated_data['cart_id'],
ignore_voucher_id=validated_data['voucher'].pk if validated_data.get('voucher') else None,
):
raise ValidationError(
{'seat': [_('The selected seat "{seat}" is not available.').format(seat=validated_data['seat'].name)]}
)
for q, needed in quotas_needed.items():
quotas_ok[q] -= needed
if validated_data.get('voucher'):
vouchers_ok[validated_data['voucher']] -= 1
if any(qa < 0 for qa in quotas_ok.values()):
# Safeguard, should never happen because of conditions above
raise ValidationError(error_messages['unavailable'])
cp = pserializer.create(validated_data)
d = CartPositionSerializer(cp, context=ctx).data
addons = sorted(cp.addons.all(), key=lambda a: a.pk) # order of creation, safe since they are created in the same transaction
d['addons'] = CartPositionSerializer([a for a in addons if not a.is_bundled], many=True, context=ctx).data
d['bundled'] = CartPositionSerializer([a for a in addons if a.is_bundled], many=True, context=ctx).data
results[i] = {
'success': True,
'data': d,
'errors': None,
}
except ValidationError as e:
if raise_exception:
raise
results[i] = {
'success': False,
'data': None,
'errors': as_serializer_error(e),
}
return results