修复 JudgeServer task_number 并发更新的问题

conf/views.py

@@ -146,7 +146,7 @@ class JudgeServerHeartbeatAPI(CSRFExemptAPIView):
             server.service_url = data["service_url"]
             server.ip = request.ip
             server.last_heartbeat = timezone.now()
-            server.save()
+            server.save(update_fields=["judger_version", "cpu_core", "memory_usage", "service_url", "ip", "last_heartbeat"])
         except JudgeServer.DoesNotExist:
             JudgeServer.objects.create(hostname=data["hostname"],
                                        judger_version=data["judger_version"],
@@ -157,8 +157,8 @@ class JudgeServerHeartbeatAPI(CSRFExemptAPIView):
                                        service_url=data["service_url"],
                                        last_heartbeat=timezone.now(),
                                        )
-            # 新server上线 处理队列中的，防止没有新的提交而导致一直waiting
-            process_pending_task()
+        # 新server上线 处理队列中的，防止没有新的提交而导致一直waiting
+        process_pending_task()
 
         return self.success()
 

docs/data.json

@@ -1,5 +1,13 @@
 {
   "update": [
+    {
+      "version": "2019-04-03",
+      "level": "Important",
+      "title": "2019-04-03",
+      "details": [
+        "Fix bugs in judge server scheduler"
+      ]
+    },
     {
       "version": "2019-03-25",
       "level": "Recommend",

judge/dispatcher.py

@@ -25,8 +25,10 @@ def process_pending_task():
     if cache.llen(CacheKey.waiting_queue):
         # 防止循环引入
         from judge.tasks import judge_task
-        data = json.loads(cache.rpop(CacheKey.waiting_queue).decode("utf-8"))
-        judge_task.send(**data)
+        tmp_data = cache.rpop(CacheKey.waiting_queue)
+        if tmp_data:
+            data = json.loads(tmp_data.decode("utf-8"))
+            judge_task.send(**data)
 
 
 class ChooseJudgeServer:
@@ -40,7 +42,7 @@ class ChooseJudgeServer:
             for server in servers:
                 if server.task_number <= server.cpu_core * 2:
                     server.task_number = F("task_number") + 1
-                    server.save()
+                    server.save(update_fields=["task_number"])
                     self.server = server
                     return server
         return None