perf: 组卷时改用bulk_create；fix: Inconsistent cache key

contest/quiz/templates/contest.html

@@ -39,7 +39,7 @@
  <article class="mx-auto max-w-2xl pb-6 prose">
  <form action="{% url 'quiz:contest_submit' %}" method="post">
  {% csrf_token %}
- {% for a in draft_response.answer_set.all %}
+ {% for a in answer_set.all %}
  <fieldset class="my-4 p-4 sm:px-6 lg:px-8 bg-white shadow disabled:text-gray-400"
  {% if draft_response.outdated %}disabled{% endif %}>
  <p class="text-lg my-0">

contest/quiz/views.py

@@ -22,19 +22,19 @@
 from django.views.generic import TemplateView
 
 from .constants import constants
-from .models import Choice, DraftResponse, Question
+from .models import Choice, DraftAnswer, DraftResponse, Question
 from .util import is_open, is_student, is_student_taking_contest, pass_or_forbid, student_only
 
 if TYPE_CHECKING:
  from typing import Any, Literal
 
  from django.contrib.auth.models import AnonymousUser
 
- from .models import DraftAnswer, Student, User
+ from .models import Student, User
  from .util import AuthenticatedHttpRequest
 
 
-def continue_or_finalize(student_: Student) -> bool:
+def continue_or_finalize(draft_response: DraftResponse) -> bool:
  """自动提交
 
  若草稿已超期，则定稿，否则什么也不做。
@@ -47,13 +47,9 @@ def continue_or_finalize(student_: Student) -> bool:
  https://docs.djangoproject.com/en/4.2/ref/models/instances/#django.db.models.Model.delete
  https://docs.djangoproject.com/en/4.2/ref/models/instances/#refreshing-objects-from-database
  """
- draft_response: DraftResponse = student_.draft_response
-
  if draft_response.outdated():
- # 提交之前的草稿
- cache_key = f"{student_.user}_json"
  # 从 Redis 获取现有的答案缓存
- cached_answers = cache.get(cache_key, {})
+ cached_answers = cache.get(f"{draft_response.id}_json", {})
 
  if cached_answers:
  for question_id, choice_id in cached_answers.items():
@@ -77,16 +73,18 @@ def continue_or_finalize(student_: Student) -> bool:
 
  answer.save()
 
- cache.delete(f"{student_.user}_json")
- cache.delete(f"{student_.user}_ddl")
+ cache.delete(f"{draft_response.id}_json")
+ cache.delete(f"{draft_response.id}_ddl")
+
+ # 提交之前的草稿
 
  # 1. Convert from draft
- response, answers = student_.draft_response.finalize(submit_at=timezone.now())
+ response, answers = draft_response.finalize(submit_at=timezone.now())
 
  # 2. Save
  response.save()
  response.answer_set.bulk_create(answers)
- student_.draft_response.delete()
+ draft_response.delete()
 
  return True
 
@@ -103,7 +101,7 @@ def manage_status(
  if not hasattr(student, "draft_response"):
  return "not taking"
  else:
- finalized = continue_or_finalize(student)
+ finalized = continue_or_finalize(student.draft_response)
  if finalized:
  return "deadline passed"
  else:
@@ -222,16 +220,19 @@ def contest(request: AuthenticatedHttpRequest) -> HttpResponse:
 
  # 保存
  draft_response.save()
- for q in questions:
- draft_response.answer_set.create(
- question=q,
- )
+ draft_response.answer_set.bulk_create(
+ [DraftAnswer(question=q, response=draft_response) for q in questions]
+ )
 
  return render(
  request,
  "contest.html",
  {
  "draft_response": draft_response,
+ # 为渲染模板预先从数据库查询相关内容
+ "answer_set": draft_response.answer_set.select_related(
+ "question"
+ ).prefetch_related("question__choice_set"),
  "constants": constants,
  },
  )