Additional query parameter to specify duration

[dschowta]

In order to query for a relateive time, it is better to support duration like field in HDS query.
e.g. /data/sensor1/reading?$duration=1h will fetch the data of last 1 hour.

[farshidtz]

I think this is redundant. The client can simply provide start and end times to get the equivalent and more consistent results.

[dschowta]

If I remember it right, it was for the BIMERR project requirement, where the BIF data fetcher needed this functionality. The fetcher presumably could not calculate the absolute times.

[farshidtz]

Right, we wanted to set the URL in their UI for cron-based retrieval. They had no parameter injection support for the URL.