review-fix. Shopping cart validation is now completely in serializers…

…. Finished moving validation from views to serializers.

backend/api/serializers.py

@@ -286,13 +286,6 @@ class Meta:
 class SubscriptionCreateDestroySerializer(serializers.ModelSerializer):
     """Serialization and validation of subscriptions."""
 
-    class Meta:
-        model = Subscription
-        fields = (
-            'user',
-            'author',
-        )
-
     def validate(self, data):
         if self.context['request'].method == 'POST':
             if data['user'] == data['author']:
@@ -310,6 +303,13 @@ def to_representation(self, instance):
             'request': self.context.get('request')
         }).data
 
+    class Meta:
+        model = Subscription
+        fields = (
+            'user',
+            'author',
+        )
+
 
 class SubscriptionRetrieveSerializer(CustomUserRetrieveSerializer):
     """Provides information about the author and their recipes"""
@@ -359,14 +359,6 @@ def to_representation(self, instance):
             instance['recipe'], context=context
         ).data
 
-    class Meta:
-        model = Favorite
-        fields = (
-            'id',
-            'user',
-            'recipe'
-        )
-
     def validate(self, data):
         if self.context['request'].method == 'POST':
             if Favorite.objects.filter(user=data['user'], recipe=data['recipe']).exists():
@@ -377,6 +369,14 @@ def validate(self, data):
             raise serializers.ValidationError('The recipe is not in favorites')
         return data
 
+    class Meta:
+        model = Favorite
+        fields = (
+            'id',
+            'user',
+            'recipe'
+        )
+
 
 class ShoppingCartSerializer(serializers.ModelSerializer):
     user = serializers.HiddenField(default=serializers.CurrentUserDefault())
@@ -394,6 +394,16 @@ def validate_recipe(self, value):
             f'Ingredient with id {value.id} does not exist'
         )
 
+    def validate(self, data):
+        if self.context['request'].method == 'POST':
+            if ShoppingCart.objects.filter(user=data['user'], recipe=data['recipe']).exists():
+                raise serializers.ValidationError('The recipe is already in shopping cart')
+            return data
+        if self.context['request'].method == 'DELETE':
+            if ShoppingCart.objects.filter(user=data['user'], recipe=data['recipe']).exists():
+                return data
+            raise serializers.ValidationError('The recipe is not in shopping cart')
+
     class Meta:
         model = ShoppingCart
         fields = (

backend/api/views.py

@@ -167,46 +167,34 @@ def favorite(self, request, pk):
     def shopping_cart(self, request, pk):
         user = self.request.user
         recipe = get_object_or_404(Recipe, pk=pk)
+        serializer = ShoppingCartSerializer(
+            data={'recipe': recipe.pk},
+            context={'request': request}
+        )
 
         if request.method == 'POST':
-            if recipe:
-                serializer = ShoppingCartSerializer(
-                    data={'recipe': recipe.pk},
-                    context={'request': request}
-                )
-                serializer.is_valid(raise_exception=True)
-                if not ShoppingCart.objects.filter(
-                        user=user,
-                        recipe=recipe
-                ).exists():
-                    ShoppingCart.objects.create(user=user, recipe=recipe)
-                    return Response(
-                        serializer.data,
-                        status=status.HTTP_201_CREATED
-                    )
-                return Response(
-                    {'errors': 'The recipe is already in shopping cart'},
-                    status=status.HTTP_400_BAD_REQUEST
-                )
-            else:
+            if serializer.is_valid(raise_exception=True):
+                ShoppingCart.objects.create(user=user, recipe=recipe)
                 return Response(
-                    {'errors': 'The recipe does not exist'},
-                    status=status.HTTP_400_BAD_REQUEST
+                    serializer.data,
+                    status=status.HTTP_201_CREATED
                 )
+            return Response(
+                status=status.HTTP_400_BAD_REQUEST
+            )
 
         if request.method == 'DELETE':
-            if ShoppingCart.objects.filter(user=user, recipe=recipe).exists():
+            if serializer.is_valid(raise_exception=True):
                 ShoppingCart.objects.get(user=user, recipe=recipe).delete()
                 return Response(status=status.HTTP_204_NO_CONTENT)
-            else:
-                return Response(
-                    {'errors': 'The recipe is not in shopping cart'},
-                    status=status.HTTP_400_BAD_REQUEST
-                )
+            return Response(
+                status=status.HTTP_400_BAD_REQUEST
+            )
 
     @action(
         methods=['GET'],
         detail=False,
+        permission_classes=[permissions.IsAuthenticated]
     )
     def download_shopping_cart(self, request):
         shopping_cart_ingredients = RecipeIngredient.objects.filter(

backend/foodgram/settings.py

@@ -5,7 +5,7 @@
 
 SECRET_KEY = os.getenv('SECRET_KEY', 'default_stub_key')
 
-DEBUG = False
+DEBUG = True
 
 ALLOWED_HOSTS = [
     '127.0.0.1',