大幅优化数据库查询, 升级django至1.11 LTS, 升级python至3.6.2

account/decorators.py

@@ -76,7 +76,7 @@ def check_contest_permission(func):
 
         try:
             # use self.contest to avoid query contest again in view.
-            self.contest = Contest.objects.get(id=contest_id, visible=True)
+            self.contest = Contest.objects.select_related("created_by").get(id=contest_id, visible=True)
         except Contest.DoesNotExist:
             return self.error("Contest %s doesn't exist" % contest_id)
 

account/middleware.py

@@ -1,14 +1,16 @@
 import time
-
 import pytz
+
 from django.contrib import auth
 from django.utils import timezone
 from django.utils.translation import ugettext as _
+from django.db import connection
+from django.utils.deprecation import MiddlewareMixin
 
 from utils.api import JSONResponse
 
 
-class SessionSecurityMiddleware(object):
+class SessionSecurityMiddleware(MiddlewareMixin):
     def process_request(self, request):
         if request.user.is_authenticated() and request.user.is_admin_role():
             if "last_activity" in request.session:
@@ -20,15 +22,27 @@ class SessionSecurityMiddleware(object):
             request.session["last_activity"] = time.time()
 
 
-class AdminRoleRequiredMiddleware(object):
+class AdminRoleRequiredMiddleware(MiddlewareMixin):
     def process_request(self, request):
         path = request.path_info
         if path.startswith("/admin/") or path.startswith("/api/admin/"):
-            if not(request.user.is_authenticated() and request.user.is_admin_role()):
+            if not (request.user.is_authenticated() and request.user.is_admin_role()):
                 return JSONResponse.response({"error": "login-required", "data": _("Please login in first")})
 
 
-class TimezoneMiddleware(object):
+class TimezoneMiddleware(MiddlewareMixin):
     def process_request(self, request):
         if request.user.is_authenticated():
             timezone.activate(pytz.timezone(request.user.userprofile.time_zone))
+
+
+class LogSqlMiddleware(MiddlewareMixin):
+    def process_response(self, request, response):
+        print("\033[94m", "#" * 30, "\033[0m")
+        time_threshold = 0.03
+        for query in connection.queries:
+            if float(query["time"]) > time_threshold:
+                print("\033[93m", query, "\n", "-" * 30, "\033[0m")
+            else:
+                print(query, "\n", "-" * 30)
+        return response

account/views/oj.py

@@ -47,7 +47,7 @@ class UserProfileAPI(APIView):
                 user = request.user
         except User.DoesNotExist:
             return self.error("User does not exist")
-        profile = UserProfile.objects.get(user=user)
+        profile = UserProfile.objects.select_related("user").get(user=user)
         return self.success(UserProfileSerializer(profile).data)
 
     @validate_serializer(EditUserProfileSerializer)