The IceBridge Portal shows a polar stereographic projection of either the northern or southern hemisphere, depending on the user's interest. For the selected hemisphere, we show a list of collections that are (a) IceBridge datasets, and (b) have a bounding box that intersects with the hemisphere they are viewing (e.g., for the northern hemisphere, a bounding box of [-180, 0, 180, 90]). For each collection, we show two counts: (i) the number of granules that match the user's current temporal and spatial filters, and (ii) the total number of granules in the hemisphere for that collection. So it looks something like this if the user hasn't set any temporal or spatial filters:
| Dataset | Granules in constraint | Granules in hemisphere |
|---|---|---|
IAKST1B Version 001 | 123 | 123 |
IDCSI4 Version 001 | 46 | 46 |
IDHDT4 Version 001 | 204 | 204 |
When they change their temporal or spatial filters, we'd like to update the first count--the count showing the number of granules for those filters, e.g.:
| Dataset | Granules in constraint | Granules in hemisphere |
|---|---|---|
IAKST1B Version 001 | 13 | 123 |
IDCSI4 Version 001 | 0 | 46 |
IDHDT4 Version 001 | 93 | 204 |
Along with this list view, there is a map which displays granules that they've selected to view. For now, I'm not interested in the granule queries we're doing against CMR.
Currently we're doing something bad and inefficient in IceBridge Portal. This was an initial attempt to get feedback to the user more quickly so they could see a more responsive interface. So basically I'm apologizing in advance for what I'm about to say .
We do three types of queries to populate the list with counts shown above:
https://cmr.earthdata.nasa.gov/search/collections.json?keyword=icebridge&page_size=100&temporal=2009-01-01T07:00:00.000Z,2016-01-28T16:19:34.258Z&bounding_box=-180,0,180,90 |
https://cmr.earthdata.nasa.gov/search/collections.json?keyword=icebridge&page_size=100&bounding_box=-180,0,180,90&include_granule_counts=true&concept_id=C1000000341-NSIDC_ECS |
This gets the number of granules for the entire northern hemisphere for one specific collection. So here's the bad part: we issue this query for each collection returned from query #1 above (!). For IceBridge, this is 50-60 queries.
Whenever a user changes temporal or spatial filters, we again issue query #2, but with their temporal and spatial filters, e.g.:
https://cmr.earthdata.nasa.gov/search/collections.json?keyword=icebridge&page_size=100&temporal=2009-01-01T07:00:00.000Z,2016-02-01T21:15:36.639Z&polygon=-54.28856753366417,70.20590793535574,-53.76512809420709,69.05817167534093,-51.035282396612224,69.18466321053025,-51.39895662736889,70.340404805645,-54.28856753366417,70.20590793535574&include_granule_counts=true&concept_id=C1000000180-NSIDC_ECS |
Again, we know this is bad, but we do a separate query for each collection in their list (~50-60 collections / queries). So doing queries 2 and 3, even though we issue lots of queries, the users see results coming back immediately, rather than waiting 5 seconds to get all the results.
https://cmr.earthdata.nasa.gov/search/collections.json?keyword=icebridge&page_size=100&temporal=2009-01-01T07:00:00.000Z,2016-01-28T16:19:34.258Z&bounding_box=-180,0,180,90&include_granule_counts=true |
(just query #1 with granule counts) We did start with this, but the query was taking 10-20s at the time, IIRC. That's why we switched to the set of queries shown above. It seems now that this query runs quite a bit faster than it did. So it's quite possible that we could switch back to it (see below).
When the user changes their filters, issue one CMR query to get a list of IceBridge collections with a specific temporal and spatial filter, along with matching granule counts. E.g.:
https://cmr.earthdata.nasa.gov/search/collections.json?keyword=icebridge&page_size=100&temporal=2009-01-01T07:00:00.000Z,2016-02-01T21:15:36.639Z&polygon=-54.28856753366417,70.20590793535574,-53.76512809420709,69.05817167534093,-51.035282396612224,69.18466321053025,-51.39895662736889,70.340404805645,-54.28856753366417,70.20590793535574&include_granule_counts=true |