_isResponseDateFresh store with service time ; but get with local time?

[wxungang]

packages/workbox-cache-expiration/plugin.mjs

  _isResponseDateFresh(cachedResponse) {
    if (!this._maxAgeSeconds) {
      // We aren't expiring by age, so return true, it's fresh
      return true;
    }

    // Check if the 'date' header will suffice a quick expiration check.
    // See https://github.com/GoogleChromeLabs/sw-toolbox/issues/164 for
    // discussion.
    const dateHeaderTimestamp = this._getDateHeaderTimestamp(cachedResponse);
    if (dateHeaderTimestamp === null) {
      // Unable to parse date, so assume it's fresh.
      return true;
    }

    // If we have a valid headerTime, then our response is fresh iff the
    // headerTime plus maxAgeSeconds is greater than the current time.
    const now = Date.now();
   //todo:  if local time is later then service time？
    return dateHeaderTimestamp >= now - (this._maxAgeSeconds * 1000);
  }

question：
//todo: if local time is later then service time？

const now = Date.now();
return dateHeaderTimestamp >= now - (this._maxAgeSeconds * 1000);

[EvsChen]

Hi @wxungang. Here is my naive understanding.
If you're referring to time zone by "local time later than service time", both Date header and Date.now() are in UTC. They will return the same number no matter which time zone you're in.
Refer to Headers/Date and Date.now() for details on Date.
If you're not talking about time zone, pls further clarify your problem.

[wxungang]

@EvsChen not about time zone 。Time is out of sync between local and server in the same time zone!

we have set maxAgeSeconds:5*60 (5min)。
but the local time（now) - server time (dateHeaderTimestamp) > maxAgeSeconds。
so the response expired always

[jadjoubran]

@wxungang have you tested that this is actually what's happening?
Because I don't think the timezone on your server matters as the time workbox is comparing against the time the document was received and as @EvsChen mentioned everything is in UTC.

Feel free to post your configuration (the service worker code that uses maxAgeSeconds) so that I can check what's wrong