修复没有点击操作时产生缓存空的bug

contest/contest/settings.py

@@ -256,7 +256,8 @@ def _debug_only(*args) -> tuple:
     }
 }
 
-# 防止本地注册表出现损坏导致的MIME类型解析错误，导致后端无法处理JS文件,有MIME报错的时候可以解除注释然后强制刷新前端运行看看
+# 防止本地注册表出现损坏导致的MIME类型解析错误，导致后端无法处理JS文件
+# 有MIME报错的时候可以解除注释然后强制刷新前端运行看看
 # 这个用法已经被取消，建议不要使用，而是更改注册表.js的属性
 # import mimetypes
 

contest/quiz/tests.py

@@ -243,6 +243,7 @@ def test_contest_update_view(self):
 
     def test_bad_contest_update(self):
         """暂存非法数据
+
         这里每次更新的时候没有写入后端，所以测试的话获取的应该是不对的,这里就先不要测了
         """
         self.client.force_login(self.user)

contest/quiz/views.py

@@ -255,28 +255,29 @@ def contest_submit(request: AuthenticatedHttpRequest) -> HttpResponse:
     # 从 Redis 获取现有的答案缓存
     cached_answers = cache.get(cache_key, {})
 
-    for question_id, choice_id in cached_answers.items():
-        # Filter out tokens
-        if not question_id.startswith("question-"):
-            continue
-
-        if not isinstance(choice_id, str) or not choice_id.startswith("choice-"):
-            return HttpResponseBadRequest(
-                f"Invalid choice ID “{choice_id}” for “{question_id}”."
-            )
+    if cached_answers is not None:
+        for question_id, choice_id in cached_answers.items():
+            # Filter out tokens
+            if not question_id.startswith("question-"):
+                continue
 
-        answer: DraftAnswer = get_object_or_404(
-            draft_response.answer_set,
-            question_id=int(question_id.removeprefix("question-")),
-        )
+            if not isinstance(choice_id, str) or not choice_id.startswith("choice-"):
+                return HttpResponseBadRequest(
+                    f"Invalid choice ID “{choice_id}” for “{question_id}”."
+                )
 
-        answer.choice = get_object_or_404(
-            Choice.objects,
-            pk=int(choice_id.removeprefix("choice-")),
-            question=answer.question,
-        )
+            answer: DraftAnswer = get_object_or_404(
+                draft_response.answer_set,
+                question_id=int(question_id.removeprefix("question-")),
+            )
 
-        answer.save()
+            answer.choice = get_object_or_404(
+                Choice.objects,
+                pk=int(choice_id.removeprefix("choice-")),
+                question=answer.question,
+            )
+
+            answer.save()
 
     # 1. Convert from draft
     response, answers = student.draft_response.finalize(submit_at=timezone.now())