Batch performant discover_nhdplus_id

[mhweber]

Currently the StreamCatTools sc_get_comid() function is calling discover_nhdplus_id to derive NHDPlus COMIDs for sets of lat and lons values. A number of users have recently been trying to speed this up through parallelizing or sending batch requests that exceed server limit in underlying NLDI service.

StreamCatTools has a similar function called lc_get_comid which calls nhdplusTools get_waterbodies and pulls NHDPlus waterbody COMIDs from the subset features.

Would calling NHDPlus subset service directly or via nhdplusTools be more performant and robust than discover_nhdplus_id for large calls to derive COMIDs for a large set of lat and lons?

[dblodgett-usgs]

Thanks for prompting this, @mhweber -- I've run into this use case a few times where people have long lists and end up using patterns that don't scale well. I'll look at an alternate discover_nhdplus_id implementation and put some thought into whether there is a faster way to do it via geoserver services.

[dblodgett-usgs]

I just merged a change that will help a bit. Will leave this open and think about whether there's a more significant update where we could do a spatial join remotely to retrieve comids.