This is great @pat! I was actually thinking of writing up a proposal for a core convention for time tracking.
Worth noting, @paul121 also started some work on a “Time” quantity type: Time quantities [#3196844] | Drupal.org
The key features that this quantity type would add are:
- A user reference field to indicate which user was tracking time
- A start time field for storing the timestamp when they “clocked in”
- A stop time field for storing the timestamp when they “clocked out”
See that feature request for more details on the reasoning behind these things.
We basically shelved that during the 2.x development push because it wasn’t a high priority, but I’d love to dust it off and think about it again!