feat: websockets

backoffice/consumers.py

@@ -0,0 +1,27 @@
+import json
+
+from channels.generic.websocket import AsyncWebsocketConsumer
+from django.utils.html import escape
+
+
+class EchoConsumer(AsyncWebsocketConsumer):
+    """Consumer mínimo para verificar el cableado de Channels + htmx (ver
+    ws_demo.html). No representa ninguna funcionalidad real todavía."""
+
+    async def connect(self):
+        # Mismo criterio de acceso que BackofficeAccessMixin.
+        if not self.scope['user'].is_staff:
+            await self.close()
+            return
+
+        await self.accept()
+
+    async def receive(self, text_data):
+        try:
+            payload = json.loads(text_data)
+        except (TypeError, ValueError):
+            payload = {}
+
+        message = escape(payload.get('message', ''))
+
+        await self.send(text_data=f'<div id="ws-demo-log" hx-swap-oob="beforeend"><p>Eco: {message}</p></div>')

backoffice/routing.py

@@ -0,0 +1,7 @@
+from django.urls import re_path
+
+from backoffice.consumers import EchoConsumer
+
+websocket_urlpatterns = [
+    re_path(r'^ws/backoffice/echo/$', EchoConsumer.as_asgi()),
+]

backoffice/templates/backoffice/products/_variant_form_fragment.html

@@ -50,6 +50,23 @@
     {{ form.attribute_values.errors }}
   </div>
 
+  {% if price_form %}
+    <div class="mb-4 max-w-md">
+      <h4 class="text-sm font-medium opacity-70 mb-1">Precio inicial (opcional)</h4>
+      <div class="grid grid-cols-1 sm:grid-cols-2 gap-4">
+        <div>
+          {{ price_form.price }}
+          {{ price_form.price.errors }}
+        </div>
+        <div>
+          {{ price_form.tax }}
+          {{ price_form.tax.errors }}
+        </div>
+      </div>
+      {{ price_form.non_field_errors }}
+    </div>
+  {% endif %}
+
   {{ form.non_field_errors }}
 
   <div class="modal-action">

backoffice/templates/backoffice/ws_demo.html

@@ -0,0 +1,24 @@
+{% extends 'backoffice/base.html' %}
+
+{% block title %}Demo WebSocket{% endblock %}
+
+{% block extra_js %}
+  <script src="https://unpkg.com/htmx-ext-ws@2.0.1/ws.js"></script>
+{% endblock %}
+
+{% block main %}
+  <h1 class="text-2xl font-semibold mb-4">Demo WebSocket</h1>
+  <p class="mb-4 opacity-70">
+    Verifica el cableado de Django Channels + htmx: el formulario envía el mensaje por WebSocket y
+    <code>EchoConsumer</code> lo devuelve como HTML que se añade al registro de abajo.
+  </p>
+
+  <div hx-ext="ws" ws-connect="/ws/backoffice/echo/" class="max-w-md">
+    <form ws-send class="flex gap-2 mb-4">
+      <input type="text" name="message" class="input input-bordered w-full" placeholder="Escribe un mensaje" autocomplete="off">
+      <button class="btn btn-primary">Enviar</button>
+    </form>
+  </div>
+
+  <div id="ws-demo-log" class="flex flex-col gap-1 max-w-md"></div>
+{% endblock %}

backoffice/tests/test_access.py

@@ -29,3 +29,17 @@ class TestBackofficeAccess(TestCase):
 
         response = self.client.get(reverse('backoffice:product_list'))
         assert response.status_code == 403
+
+    def test_non_staff_user_gets_forbidden_on_ws_demo(self):
+        user = User.objects.create_user('leia', 'leia@rebels.com', 'ihatesand', is_staff=False)
+        self.client.force_login(user)
+
+        response = self.client.get(reverse('backoffice:ws_demo'))
+        assert response.status_code == 403
+
+    def test_superuser_can_access_ws_demo(self):
+        user = User.objects.create_superuser('vader2', 'vader2@empire.com', 'ihatesand')
+        self.client.force_login(user)
+
+        response = self.client.get(reverse('backoffice:ws_demo'))
+        assert response.status_code == 200

backoffice/tests/test_products.py

@@ -140,6 +140,33 @@ class TestBackofficeProducts(TestCase, CreateProductsMixin):
         assert variant.product == self.product
         assert size_m in variant.attribute_values.all()
 
+    def test_create_variant_with_initial_price_in_one_submit(self):
+        # El staff introduce el precio CON impuestos; se guarda sin impuestos,
+        # igual que en la creación de producto (ver ProductInitialPriceForm).
+        tax, created = Tax.objects.get_or_create(code='IVA', value=21)
+        size_m = self.create_attribute_value('Talla', 'M')
+
+        response = self.client.post(
+            reverse('backoffice:product_variant_create', args=[self.product.pk]),
+            {'sku': 'V-M', 'stock': '5', 'attribute_values': [size_m.pk], 'price': '19.99', 'tax': tax.pk},
+        )
+        assert response.status_code == 302
+        variant = ProductVariant.objects.get(sku='V-M')
+        price = ProductPrice.objects.get(variant=variant)
+        assert price.price == Decimal('16.52')
+        assert price.price_with_tax == Decimal('19.99')
+        assert price.current is True
+
+    def test_create_variant_with_price_missing_tax_shows_error(self):
+        size_m = self.create_attribute_value('Talla', 'M')
+
+        response = self.client.post(
+            reverse('backoffice:product_variant_create', args=[self.product.pk]),
+            {'sku': 'V-M', 'stock': '5', 'attribute_values': [size_m.pk], 'price': '19.99'},
+        )
+        assert response.status_code == 200
+        assert not ProductVariant.objects.filter(sku='V-M').exists()
+
     def test_create_duplicated_variant_combination_fails(self):
         size_m = self.create_attribute_value('Talla', 'M')
         self.create_product_variant(self.product, sku='V-M1', attribute_values=[size_m])

backoffice/urls/__init__.py

@@ -1,11 +1,13 @@
 from django.urls import include, path
 
 from backoffice.views.dashboard import DashboardView
+from backoffice.views.ws_demo import WebSocketDemoView
 
 app_name = 'backoffice'
 
 urlpatterns = [
     path('', DashboardView.as_view(), name='dashboard'),
+    path('ws-demo/', WebSocketDemoView.as_view(), name='ws_demo'),
     path('products/', include('backoffice.urls.products')),
     path('orders/', include('backoffice.urls.orders')),
     path('payments/', include('backoffice.urls.payments')),

backoffice/views/products.py

@@ -350,11 +350,32 @@ class ProductVariantCreateView(ProductVariantAttributesContextMixin, BackofficeC
     def get_context_data(self, **kwargs):
         context = super().get_context_data(**kwargs)
         product = self.get_product()
+        context.setdefault('price_form', ProductInitialPriceForm())
         context.update(
             {'title': f'Añadir variante a {product.name}', 'cancel_url': reverse_lazy('backoffice:product_detail', args=[product.pk])}
         )
         return context
 
+    def form_valid(self, form):
+        # El precio es opcional y se crea en el mismo envío que la variante,
+        # igual que en ProductCreateView (ver ProductInitialPriceForm).
+        price_form = ProductInitialPriceForm(self.request.POST)
+
+        if not price_form.is_valid():
+            return self.render_to_response(self.get_context_data(form=form, price_form=price_form))
+
+        response = super().form_valid(form)
+
+        if price_form.cleaned_data.get('price') is not None:
+            ProductPrice.objects.create(
+                variant=self.object,
+                price=price_form.get_price_without_tax(),
+                tax=price_form.cleaned_data['tax'],
+                current=True,
+            )
+
+        return response
+
     def get_success_url(self):
         return reverse_lazy('backoffice:product_detail', args=[self.object.product_id])
 

backoffice/views/ws_demo.py

@@ -0,0 +1,11 @@
+from django.views.generic import TemplateView
+
+from backoffice.mixins import BackofficeAccessMixin
+
+
+class WebSocketDemoView(BackofficeAccessMixin, TemplateView):
+    """Verifica el cableado de Channels + htmx (ver EchoConsumer). No es una
+    funcionalidad real, solo la base para construir encima."""
+
+    template_name = 'backoffice/ws_demo.html'
+    section = 'ws_demo'