fangke/server/tracker/services/stats.py

from datetime import datetime, time, timedelta
from django.utils import timezone
from tracker.models import DailyStat, Event, VisitSession, Visitor


def daily_counts(site, date) -> dict:
    """四指标共享口径（site=None 聚合全部站点）。所有指标排除爬虫。

    日界取 TIME_ZONE（Asia/Shanghai）自然日：make_aware(datetime.combine(date, time.min))。
    口径：pv/uv 均从事件表统计（排除 is_bot），uv=distinct visitor，与 pv 同源；
    sessions 按会话 started_at 落入当日且访客非爬虫；new_visitors 按 Visitor.first_seen_at 落入当日。
    refresh_daily 落库与 dashboard 今日实时位共用此函数，防两处口径漂移（Task8 审查结论）。
    """
    day_start = timezone.make_aware(datetime.combine(date, time.min))
    day_end = day_start + timedelta(days=1)
    ev = Event.objects.filter(is_bot=False,
                              occurred_at__gte=day_start, occurred_at__lt=day_end)
    vs = VisitSession.objects.filter(visitor__is_bot=False,
                                     started_at__gte=day_start, started_at__lt=day_end)
    vis = Visitor.objects.filter(is_bot=False,
                                 first_seen_at__gte=day_start, first_seen_at__lt=day_end)
    if site is not None:
        ev = ev.filter(site=site)
        vs = vs.filter(site=site)
        vis = vis.filter(site=site)
    return {"pv": ev.count(),
            "uv": ev.values("visitor").distinct().count(),
            "sessions": vs.count(),
            "new_visitors": vis.count()}


def refresh_daily(site, date) -> DailyStat:
    """重算某站点某自然日的聚合（幂等，update_or_create）。指标口径见 daily_counts。"""
    obj, _ = DailyStat.objects.update_or_create(site=site, date=date,
                                                defaults=daily_counts(site, date))
    return obj