Some more optimizations

judge/models/problem.py

@@ -6,7 +6,7 @@ from django.contrib.contenttypes.fields import GenericRelation
 from django.core.cache import cache
 from django.core.validators import MaxValueValidator, MinValueValidator, RegexValidator
 from django.db import models
-from django.db.models import CASCADE, F, FilteredRelation, Q, SET_NULL
+from django.db.models import CASCADE, F, FilteredRelation, Q, SET_NULL, Exists, OuterRef
 from django.db.models.functions import Coalesce
 from django.urls import reverse
 from django.utils.functional import cached_property
@@ -369,7 +369,7 @@ class Problem(models.Model):
         )
 
     @classmethod
-    def get_visible_problems(cls, user):
+    def get_visible_problems(cls, user, profile=None):
         # Do unauthenticated check here so we can skip authentication checks later on.
         if not user.is_authenticated or not user:
             return cls.get_public_problems()
@@ -383,7 +383,7 @@ class Problem(models.Model):
         #           - not is_organization_private or in organization or `judge.see_organization_problem`
         #           - author or curator or tester
         queryset = cls.objects.defer("description")
-
+        profile = profile or user.profile
         if not (
             user.has_perm("judge.see_private_problem")
             or user.has_perm("judge.edit_all_problem")
@@ -393,13 +393,25 @@ class Problem(models.Model):
                 # Either not organization private or in the organization.
                 q &= Q(is_organization_private=False) | Q(
                     is_organization_private=True,
-                    organizations__in=user.profile.organizations.all(),
+                    organizations__in=profile.organizations.all(),
                 )
 
             # Authors, curators, and testers should always have access, so OR at the very end.
-            q |= Q(authors=user.profile)
-            q |= Q(curators=user.profile)
-            q |= Q(testers=user.profile)
+            filter = Exists(
+                Problem.authors.through.objects.filter(
+                    problem=OuterRef("pk"), profile=profile
+                )
+            )
+            filter |= Exists(
+                Problem.curators.through.objects.filter(
+                    problem=OuterRef("pk"), profile=profile
+                )
+            )
+            filter |= Exists(
+                Problem.testers.through.objects.filter(
+                    problem=OuterRef("pk"), profile=profile
+                )
+            )
             queryset = queryset.filter(q)
 
         return queryset