Status: Won't Fix
Fix Version/s: None
Team:Data Access and Database
The goal should be a proof of concept implementation of an SIA V2 metadata interface.
Some goals of this ticket:
• Develop understanding of ObsCore metadata and how it relates to current metadata
• Develop ObsCore tables of W13 SDSS Image Metadata
• Be able to return a URL to imgserv which can return an image for SDSS data
• Develop an ObsCore metadata loading mechanism, ideally based on SQLAlchemy so we aren't tied to a specific database
• May reuse data from WISE SIA V2 interface/ObsCore tables at IRSA
- Out of scope is copying WISE images to PDAC, we can rely on the accessUrls at IRSA
VOTable XML output may be generated from the VOTable XML template in dbserv:
For examples of SIA queries which work at IPAC:
(from https://irsa.ipac.caltech.edu/ibe/sia.html#examples )
- Search for ALLWISE images within 10 arcseconds of ra,dec = (19.005875, -5.084472). Return the result as in comma-separated value format.
wget -O example1.csv "https://irsa.ipac.caltech.edu/SIA?COLLECTION=wise_allwise&POS=circle+-164.7+-5.8+0.002777&RESPONSEFORMAT=CSV"
- Return only the WISE channel 1 data products.
wget -O example2.csv "https://irsa.ipac.caltech.edu/SIA?COLLECTION=wise_allwise&POS=circle+-164.7+-5.8+0.002777&RESPONSEFORMAT=CSV&BAND=3.4e-6"
- Return only data products that are FITS images (as opposed to gzipped files or text files).
wget -O example3.csv "https://irsa.ipac.caltech.edu/SIA?COLLECTION=wise_allwise&POS=circle+-164.7+-5.8+0.002777&RESPONSEFORMAT=CSV&BAND=3.4e-6&FORMAT=image/fits"
- is duplicated by
DM-18322 Implement SIA as DAX interface to access image metadata from obscore
- Won't Fix
Kenny has transitioned off the DAX team, and further work on ObsCore is separately ticketed and resourced on the SQuaRE team.
Note on Implementation for positional searches:
POS is the keyword that will be most interesting for spatial searches:
In ObsCore, you store the s_region column as a string, which isn't quite indexable as-is, and there's no such things as corners like we have in ScienceCcdExposure. However, we are allowed to have extra columns, so we can have the corner columns and do the spatial searches that way using the scisql UDFs.
When importing data that's not ours, especially that which derives also from ObsTAP/SIA, that may mean we need to extract the corners of an image from the s_region column just to make sure things work smoothly with scisql.