Fix le panier de l'Eboutic pour Safari (#518)

Co-authored-by: Théo DURR <git@theodurr.fr>
Co-authored-by: thomas girod <56346771+imperosol@users.noreply.github.com>

eboutic/forms.py

@@ -26,8 +26,10 @@ import json
 import re
 import typing
 
+from urllib.parse import unquote
 from django.http import HttpRequest
 from django.utils.translation import gettext as _
+from sentry_sdk import capture_message
 
 from eboutic.models import get_eboutic_products
 
@@ -97,23 +99,34 @@ class BasketForm:
             - all the ids refer to products the user is allowed to buy
             - all the quantities are positive integers
         """
-        basket = self.cookies.get("basket_items", None)
+        basket = unquote(self.cookies.get("basket_items", None))
         if basket is None or basket in ("[]", ""):
             self.error_messages.add(_("You have no basket."))
             return
+
         # check that the json is not nested before parsing it to make sure
-        # malicious user can't ddos the server with deeply nested json
+        # malicious user can't DDoS the server with deeply nested json
         if not BasketForm.json_cookie_re.match(basket):
+            # As the validation of the cookie goes through a rather boring regex,
+            # we can regularly have to deal with subtle errors that we hadn't forecasted,
+            # so we explicitly lay a Sentry message capture here.
+            capture_message(
+                "Eboutic basket regex checking failed to validate basket json",
+                level="error",
+            )
             self.error_messages.add(_("The request was badly formatted."))
             return
+
         try:
             basket = json.loads(basket)
         except json.JSONDecodeError:
             self.error_messages.add(_("The basket cookie was badly formatted."))
             return
+
         if type(basket) is not list or len(basket) == 0:
             self.error_messages.add(_("Your basket is empty."))
             return
+
         for item in basket:
             expected_keys = {"id", "quantity", "name", "unit_price"}
             if type(item) is not dict or set(item.keys()) != expected_keys: