# improved mosq task

apps/mosquito/tasks.py

@@ -20,53 +20,60 @@ def shortest_date(date, date_list):
     return shortest_distance
 
 
-@task()
-def update_daily_statistic():
-    # calc_ret = {}
-    # queryset = DeviceCount.objects.raw(
-    #     'select id, device_id, max(data_time) as max_date '
-    #     'from device_count group by device_id, date(data_time) order by max_date')
-    #
-    # if queryset:
-    #     ret = []
-    #     for q in queryset:
-    #         entry = DeviceCount.objects.filter(device_id=q.device_id, data_time=q.max_date)
-    #         entry = reduce(max_count, entry) if len(entry) > 1 else entry[0]
-    #         ret.append((entry.data_time.date(), int(entry.count)))
-    #     if ret:
-    #         for item in ret:
-    #             key, value = item[0], item[1]
-    #             try:
-    #                 calc_ret[key] += value
-    #             except KeyError:
-    #                 calc_ret[key] = value
+def fill_date(ret=None, tz=None):
+    date_list = [k for k in ret]
+    min_date = min(date_list)
+    max_date = datetime.now(tz).date()
+    days = (max_date - min_date).days
+    for d in range(1, days + 1):
+        date_ahead = min_date + timedelta(days=d)
+        if date_ahead not in ret:
+            distance = shortest_date(date_ahead, date_list)
+            ret[date_ahead] = ret[date_ahead - timedelta(days=distance)]
+    return ret
+
+
+def get_daily_statistic(SPLIT_BY_DEVICE=False):
     queryset = DeviceCount.objects.raw('select id, date(data_time) as date from device_count group by date')
     if queryset:
+        calc_result = {}
         tz = pytz.timezone("UTC")
+        device_list = {item.device_id for item in DeviceCount.objects.distinct()}
+        for item in device_list:
+            calc_result[item] = []
         ret = {}
         for q in queryset:
+            # 按照 device_id 分组查询最新时间 max_time，然后通过id + max_time 获取实例，用来得到count
             midnight = tz.localize(datetime.combine(q.date, time(23, 59)), is_dst=None)
             daily_queryset = [DeviceCount.objects.filter(device_id=x['device_id'], data_time=x['max_time'])
                               for x in DeviceCount.objects.filter(data_time__lte=midnight).values(
                     'device_id').annotate(max_time=Max('data_time'))]
             if daily_queryset:
                 daily_queryset = [reduce(max_count, entry) if len(entry) > 1 else entry[0] for entry in daily_queryset]
+                if SPLIT_BY_DEVICE:
+                    for device_id in device_list:
+                        calc_result[device_id] += [entry for entry in daily_queryset if entry.device_id == device_id]
+                else:
                     calc_result = sum(map(lambda x: int(x.count), daily_queryset))
                 date = q.date
                 ret[date] = calc_result
-        date_list = [k for k in ret]
-        min_date = min(date_list)
-        # max_date = max(date_list)
-        max_date = datetime.now(tz).date()
-        days = (max_date - min_date).days
-        for d in range(1, days+1):
-            date_ahead = min_date + timedelta(days=d)
-            if date_ahead not in ret:
-                distance = shortest_date(date_ahead, date_list)
-                ret[date_ahead] = ret[date_ahead - timedelta(days=distance)]
 
-        # Update statistic to MosqPostStatistic
-        _date_list = [k for k in ret]
+        return ret
+    return None
+
+@task()
+def update_daily_statistic():
+    full_ret = None
+    # 计算每天聚合值
+    daily_ret = get_daily_statistic()
+
+    # 计算没有记录的日期，值
+    if daily_ret:
+        full_ret = fill_date(daily_ret, tz=pytz.timezone("UTC"))
+
+    # 写入数据库
+    if full_ret:
+        _date_list = [k for k in full_ret]
         _date_list.sort()
         is_first = True
         for d in _date_list:
@@ -76,17 +83,17 @@ def update_daily_statistic():
                 obj = None
             if is_first:
                 if obj:
-                    obj.total, obj.increment = ret[d], ret[d]
+                    obj.total, obj.increment = full_ret[d], full_ret[d]
                     obj.save()
                 else:
-                    MosqPostStatistic.objects.create(date=d, total=ret[d], increment=ret[d])
+                    MosqPostStatistic.objects.create(date=d, total=full_ret[d], increment=full_ret[d])
             else:
-                increment = ret[d] - ret[d-timedelta(days=1)]
+                increment = full_ret[d] - full_ret[d-timedelta(days=1)]
                 if obj:
-                    obj.total, obj.increment = ret[d], increment
+                    obj.total, obj.increment = full_ret[d], increment
                     obj.save()
                 else:
-                    MosqPostStatistic.objects.create(date=d, total=ret[d], increment=increment)
+                    MosqPostStatistic.objects.create(date=d, total=full_ret[d], increment=increment)
             is_first = False
         return _date_list