From 283441bbc4ce83f63dab22f46e935c32c98d2d6c Mon Sep 17 00:00:00 2001
From: mohsentaba <s.hosseintaba98@gmail.com>
Date: Sun, 26 Apr 2026 11:15:52 +0330
Subject: [PATCH] professor details caching enhancement

professors course list is cache cleared now

signal added to clear cache after any change happend in the professor object
---
 apps/course/signals.py         | 30 ++++++++++++++++++++++++++----
 apps/course/views/professor.py | 28 ++++++++++++++++++++++++++++
 2 files changed, 54 insertions(+), 4 deletions(-)

diff --git a/apps/course/signals.py b/apps/course/signals.py
index 1048c84..4074622 100644
--- a/apps/course/signals.py
+++ b/apps/course/signals.py
@@ -1,9 +1,13 @@
-from django.db.models.signals import post_save
-from django.dispatch import receiver
-
 from apps.course.models import Course
 from apps.chat.models import RoomMessage
 
+from django.db.models.signals import post_save, post_delete
+from django.dispatch import receiver
+from django.core.cache import cache
+from django.contrib.auth import get_user_model
+
+UserModel = get_user_model()
+
 
 @receiver(post_save, sender=Course)
 def handle_room_message_for_course(sender, instance, created, **kwargs):
@@ -31,4 +35,22 @@ def handle_room_message_for_course(sender, instance, created, **kwargs):
 def ensure_professor_role(sender, instance, **kwargs):
     professor = getattr(instance, 'professor', None)
     if professor:
-        professor.ensure_professor_profile()
\ No newline at end of file
+        professor.ensure_professor_profile()
+
+@receiver([post_save, post_delete], sender=Course)
+def invalidate_professor_course_cache(sender, instance, **kwargs):
+    """
+    Clears the cached professor detail page AND their course list 
+    whenever a course assigned to them is created, updated, or deleted.
+    """
+    if instance.professor:
+        detail_cache_key = f"professor_detail_{instance.professor.slug}"
+        
+        cache.delete(detail_cache_key)
+
+# Optional: If you update a Professor's profile in the admin directly
+@receiver([post_save, post_delete], sender=UserModel)
+def invalidate_professor_profile_cache(sender, instance, **kwargs):
+    if instance.user_type == UserModel.UserType.PROFESSOR:
+        cache_key = f"professor_detail_{instance.slug}"
+        cache.delete(cache_key)
\ No newline at end of file
diff --git a/apps/course/views/professor.py b/apps/course/views/professor.py
index 287b58c..2cdf251 100644
--- a/apps/course/views/professor.py
+++ b/apps/course/views/professor.py
@@ -15,6 +15,10 @@ from apps.course.serializers import (
     ProfessorListSerializer,
 )
 from utils.pagination import StandardResultsSetPagination
+from django.utils.decorators import method_decorator
+from django.views.decorators.cache import never_cache
+from django.core.cache import cache
+from rest_framework.response import Response
 
 
 UserModel = get_user_model()
@@ -108,6 +112,25 @@ class ProfessorDetailAPIView(RetrieveAPIView):
     def get(self, request, *args, **kwargs):
         return super().get(request, *args, **kwargs)
 
+    def retrieve(self, request, *args, **kwargs):
+        slug = self.kwargs.get('slug')
+        cache_key = f"professor_detail_{slug}"
+        
+        # Try to get the data from Redis/Cache
+        cached_data = cache.get(cache_key)
+        if cached_data:
+            return Response(cached_data)
+
+        # If not in cache, let DRF do the heavy lifting (DB queries, serialization)
+        response = super().retrieve(request, *args, **kwargs)
+        
+        # Store the serialized data in the cache for 24 hours
+        cache.set(cache_key, response.data, timeout=60 * 60 * 24)
+        
+        return response
+
+
+
     def get_queryset(self):
         return UserModel.objects.filter(user_type=UserModel.UserType.PROFESSOR).annotate(
             course_count=Count('courses', distinct=True),
@@ -122,6 +145,11 @@ class ProfessorCourseListAPIView(ListAPIView):
     search_fields = ['title', 'category__name']
     pagination_class = StandardResultsSetPagination
 
+    @method_decorator(never_cache)
+    def dispatch(self, request, *args, **kwargs):
+        return super().dispatch(request, *args, **kwargs)
+
+
     @swagger_auto_schema(
         operation_description='دریافت فهرست دوره‌های فعال یک استاد مشخص‌شده با اسلاگ.',
         tags=['Imam-Javad - Course'],