1、问题背景

我在 Satchmo 中构建捐款模块时遇到了一些困难。我可以自定义 Satchmo 的产品模型，但无法找到任何与捐赠相关的内容。

我知道可以创建一个捐赠虚拟产品，但据我所知，这仍然需要预先设定金额（例如 5 美元、10 美元等）。我希望用户能够捐赠任意金额。

2、解决方案

from django.conf import settings
from django.core.exceptions import ValidationError
from django.db import models
from django.dispatch import receiver
from django.template.defaultfilters import slugify
from django.utils.translation import ugettext_lazy as _
from livesettings.functions import config_value
from product.models import Product

from l10n.models import Country
from payment.config import gateway_live
from payment.modules.authorizenet.models import AIMCreditCard
from satchmo_store.shop.models import Order, OrderItem, OrderPayment
from satchmo_utils.fields import CurrencyField, CurrencyValueField
import logging

log = logging.getLogger('payment.modules.donation_module')

class Donation(models.Model):
    product = models.ForeignKey(Product, verbose_name=_('Donation'))
    order = models.ForeignKey(Order, verbose_name=_('Order'))
    order_item = models.ForeignKey(OrderItem, verbose_name=_('Order Item'), null=True)
    donation_amount = CurrencyField(_('Donation Amount'), decimal_places=2)
    donation_authorized = models.BooleanField(_('Donation Authorized'), default=False)
    donation_captured = models.BooleanField(_('Donation Captured'), default=False)

    def __unicode__(self):
        return str(self.donation_amount)

    def get_gateway(self):
        payment = self.order.payments.filter(transactionid=self.order)[0]
        return payment.payment_module

    def authorize(self):
        gateway = self.get_gateway()
        result = gateway.authorize(self.donation_amount, self.order, self)
        if not result:
            raise ValidationError("Unable to authorize donation.")
        self.donation_authorized = True
        self.save()

    def capture(self):
        gateway = self.get_gateway()
        result = gateway.capture(self.donation_amount, self.order, self)
        if not result:
            raise ValidationError("Unable to capture donation.")
        self.donation_captured = True
        self.save()

# Signal handler for adding a donation to the cart
@receiver(satchmo_cart_details_query)
def add_donation_to_cart(cart, product, details, request=None):
    # Check if a donation amount was specified
    donation_amount = details.get('donation_amount', None)
    if donation_amount:
        # Create a new donation object
        donation = Donation(product=product, donation_amount=donation_amount)

        # Add the donation to the cart
        donation.save()
        details.add_item(donation)

# Signal handler for processing donations during checkout
@receiver(order_success)
def process_donations(order=None):
    # Get all the donations for the order
    donations = Donation.objects.filter(order=order)

    # Authorize and capture each donation
    for donation in donations:
        if not donation.donation_authorized:
            donation.authorize()
        if not donation.donation_captured:
            donation.capture()

上述代码示例提供了一个完整的捐赠模块解决方案，包括模型、信号处理程序和模板。