如何在 Django Oscar 中重写类方法

Question

目前我已经可以覆盖该类，但我无法覆盖方法 get() 我错过了什么？

我需要这样做，因为如果只有 1 种送货方式，它不会加载“送货方式”页面，而是重定向到付款页面，但我希望客户在进入付款页面之前看到运费。

apps.py

import oscar.apps.checkout.apps as apps
from oscar.core.loading import get_class
from django.urls import path

class CheckoutConfig(apps.CheckoutConfig):
    name = 'apps.checkout'
    
    def ready(self):
        self.shipping_method_view = get_class('checkout.views', 'ShippingMethodViewOverwritten')
        super().ready()

    def get_urls(self):
        urls = super(CheckoutConfig, self).get_urls()
        urls += [
            path('shipping-method/',
                self.shipping_method_view.as_view(), name='shipping-method'),
        ]
        return urls

views.py

from oscar.apps.checkout import views
from oscar.core.loading import get_class
ShippingAddressForm, ShippingMethodForm, GatewayForm \
    = get_classes('checkout.forms', ['ShippingAddressForm', 'ShippingMethodForm', 'GatewayForm'])
from django.contrib import messages
Repository = get_class('shipping.repository', 'Repository')

class ShippingMethodViewOverwritten(views.ShippingMethodView):
    template_name = 'oscar/checkout/shipping_methods.html'
    form_class = ShippingMethodForm
    pre_conditions = ['check_basket_is_not_empty',
                      'check_basket_is_valid',
                      'check_user_email_is_captured']
    success_url = reverse_lazy('checkout:payment-method')

    def get(self, request, *args, **kwargs):

        if not request.basket.is_shipping_required():
            self.checkout_session.use_shipping_method(
                NoShippingRequired().code)
            return self.get_success_response()

        if not self.checkout_session.is_shipping_address_set():
            messages.error(request, _("Please choose a shipping address"))
            return redirect('checkout:shipping-address')

        self._methods = self.get_available_shipping_methods()
        if len(self._methods) == 0:
            # No shipping methods available for given address
            messages.warning(request, _(
                "Shipping is unavailable for your chosen address - please "
                "choose another"))
            return redirect('checkout:shipping-address')
        elif len(self._methods) == 1:
            # Only one shipping method - set this and redirect onto the next
            # step
            self.checkout_session.use_shipping_method(self._methods[0].code)
            return self.get_success_response()

        return super().get(request, *args, **kwargs)

    def get_available_shipping_methods(self):
        return Repository().get_shipping_methods(basket=self.request.basket, 
        user=self.request.user,shipping_addr=self.get_shipping_address(self.request.basket), 
        request=self.request)

Answer 1

ShippingMethodView 中有一个显式逻辑，可以处理可用的单一运输方式的情况，并跳过“运输方式”选择屏幕。为了覆盖此行为，首先您需要自定义 Checkout 应用程序。请遵循

此处有关如何分叉 Oscar 应用程序的指南。

这是它在 Oscar 中的实现方式

File: oscar/apps/checkout/views.py

def get(self, request, *args, **kwargs):
            .....
            self._methods = self.get_available_shipping_methods()
        if len(self._methods) == 0:
            # No shipping methods available for given address
            messages.warning(
                request,
                _(
                    "Shipping is unavailable for your chosen address - please "
                    "choose another"
                ),
            )
            return redirect("checkout:shipping-address")
        elif len(self._methods) == 1:
            # Only one shipping method - set this and redirect onto the next
            # step
            self.checkout_session.use_shipping_method(self._methods[0].code)
            return self.get_success_response()
            .....

只需删除

elif

 块即可绕过正在设置运输方式（如果仅找到）的工作流程。