My cache needs to expire on the hour, with light expiration and heavy expiration distinctions. What should I use?

[zms9110750]

Use Case

I need to fetch statistics data from a network API, which includes two types of data:

1. Short-time data with a span of 2 hours.
2. Long-time data with a span of 1 day.

The update rule for the data is: UTC 0:00 and every 2 hours afterward. To keep the data in sync, I need the following behavior:

1. If the current time and the cached entry time are in different UTC dates, the request should be blocked until the latest data is fetched and returned.
2. If the current time and the cached entry time are in the same UTC date, the stale data should be returned immediately, while the latest data is fetched in the background.
3. The expiration time for the cache needs to be calculated dynamically, based on the time difference between the current time and the next whole hour (UTC time). It should not be fixed as two hours after the data is fetched.