API: base implementation of /cards, /card/<uuid>

Implements CatimaLoyalty#1
Implements CatimaLoyalty#2

.gitignore

@@ -153,3 +153,4 @@ cython_debug/
 #  option (not recommended) you can uncomment the following to ignore the entire idea folder.
 #.idea/
 
+_token

api/urls.py

@@ -0,0 +1,7 @@
+from django.urls import path
+from . import views
+
+urlpatterns = [
+    path("cards/", views.CardsGet.as_view()),
+    path("card/<uuid:uuid>/", views.CardGet.as_view()),
+]

api/view_utils.py

@@ -0,0 +1,52 @@
+""" Utility classes for API views """
+
+from .models import AuthToken
+import typing as t
+from django import http
+from django.views.generic.base import View
+
+if t.TYPE_CHECKING:
+    _base_view_mixin = View
+else:
+    _base_view_mixin = object
+
+
+class TokenAuthMixin(_base_view_mixin):
+    """Checks that the user provides a correct token-based auth through headers"""
+
+    auth_token: AuthToken
+
+    def dispatch(self, request, *args, **kwargs) -> http.response.HttpResponseBase:
+        token_name = request.headers.get("x-token-username", None)
+        token_secret = request.headers.get("x-token-secret", None)
+        if not token_name or not token_secret:
+            return http.JsonResponse(
+                {
+                    "reason": "No X-Token-Username or X-Token-Secret provided",
+                },
+                status=403,
+            )
+
+        token = AuthToken.check_auth(token_name, token_secret)
+        if token is None:
+            return http.JsonResponse(
+                {"reason": "Token authentication failed"},
+                status=403,
+            )
+
+        self.auth_token = token
+        return super().dispatch(request, *args, **kwargs)
+
+
+class APIView(View):
+    """A View part of the API."""
+
+    # Override to empty list by default -- prevent mistakes
+    http_method_names: list[str] = []
+
+    def http_method_not_allowed(self, request, *args, **kwargs) -> http.HttpResponse:
+        """Called when a bad method is used"""
+        return http.JsonResponse(
+            {"reason": f"{request.method} method not allowed for this endpoint."},
+            status=405,
+        )

api/views.py

@@ -1,3 +1,52 @@
-from django.shortcuts import render
+from backend import models as backend_models
+from .view_utils import TokenAuthMixin, APIView
+from django.views.generic.detail import SingleObjectMixin
+from django.views.generic.list import MultipleObjectMixin
+from django.db.models.query import QuerySet
+from django.http import JsonResponse
 
-# Create your views here.
+
+class LoyaltyCardAuthenticatedMixin(TokenAuthMixin):
+    """Restricts the queryset to the LoyaltyCards owned by the authenticated user"""
+
+    def get_queryset(self) -> QuerySet:
+        return backend_models.LoyaltyCard.objects.filter(owner=self.auth_token.user)
+
+
+class CardsGet(LoyaltyCardAuthenticatedMixin, MultipleObjectMixin, APIView):
+    """Get the list of cards of this user, mapped to their revision ID"""
+
+    http_method_names = ["get"]
+
+    def get(self, request, *args, **kwargs) -> JsonResponse:
+        cards = self.get_queryset()
+        data = {str(card.uuid): card.revision_id for card in cards}
+        return JsonResponse(data)
+
+
+class CardGet(LoyaltyCardAuthenticatedMixin, SingleObjectMixin, APIView):
+    """Get the details of a single card"""
+
+    pk_url_kwarg = "uuid"
+
+    http_method_names = ["get"]
+
+    def get(self, request, *args, **kwargs):
+        card = self.get_object()
+        data = {
+            "uuid": str(card.uuid),
+            "store": card.store,
+            "note": card.note,
+            "expiracy": card.expiracy,
+            "balance": card.balance,
+            "balance_currency": card.balance_currency,
+            "card_id": card.card_id,
+            "barcode_id": card.barcode_id_raw,
+            "header_color": card.header_color.as_hex(),
+            "star_status": card.star_status,
+            "archive_status": card.archive_status,
+            "last_used": card.last_used,
+            "zoom_level": card.zoom_level,
+            "revision_id": card.revision_id,
+        }
+        return JsonResponse(data)

catima_sync/urls.py

@@ -14,8 +14,9 @@
     2. Add a URL to urlpatterns:  path('blog/', include('blog.urls'))
 """
 from django.contrib import admin
-from django.urls import path
+from django.urls import include, path
 
 urlpatterns = [
     path("admin/", admin.site.urls),
+    path("api/", include("api.urls")),
 ]