Recommendations for TAP Service Implementation for Lite IDAC

Data Management
#1

I am currently implementing the TAP protocol layer for our Lite IDAC, and I would like to get some advice on the best TAP service for the system. Specifically, I am evaluating whether to use GAVODaCHS, PyVO,
another TAP implementation or even making our own.

Could you please share your experience or recommendations regarding the following:

  1. Which TAP service would you recommend for a project like Lite IDAC?
  2. Are there any known challenges or advantages with GAVODaCHS, PyVO, or other TAP services that are particularly relevant to LSST data or similar large-scale astronomical projects?
  3. If there are any other services or tools that you think would be more suitable for managing and querying large datasets from LSST or similar observatories, I would appreciate your input.
#2

The Rubin Science Platform’s TAP service is based on CADC’s tap service: GitHub - opencadc/tap: client and server implementation of Table Access Protocol (TAP) specification - we are very happy with it.

I am confused by your reference to PyVO. To my knowledge PyVO is a client library, and I understood your question to be about a TAP server.

We have no experience with DaCHS.

You might wish to ask on the IDAC topic to see what others IDACs are doing: Independent Data Access Centers - Rubin Observatory LSST Community forum or get in touch with your IDAC coordination group representative.

2 Likes
#3

@bmajor, is there a guide/documentation you recommend for someone trying to deploy CADC’s TAP service?

#4

… the TAP protocol layer for our Lite IDAC

Does this mean that you will be serving a subset of Rubin catalogs through this TAP service? Or is this TAP service just for supplementary data that’s unique to your IDAC?

You should be aware that if you do not do this the way that we do in the RSP, there are aspects of the normal RSP service of catalogs that will require extra work from you in order to duplicate – if this is a goal of your IDAC. Not all TAP server implementations are interchangeable in these respects.

#5

HI @SantiagoArroyoL - Yes, as Frossie says, CADC has a TAP server implementation that should fit your purposes. The deployment documentation and process is improving but may require some help from us, which we’d be happy to provide. Probably the forum mentioned above, or the IDAC slack channel is best for those questions: Slack ?

There is a TAP-server docker image here that will get you started: images.opencadc.org/core/youcat:0.7.3

Documentation on configuring this image can be found here: tap/youcat at main · opencadc/tap · GitHub

#6

Just for clarity: in the RSP we are currently running a fork of CADC TAP with a major feature added (DataLink service descriptor annotation). This feature is quite important to the overall user-facing feature set of the RSP.

We are working with CADC to get this upstreamed, but I’m not sure how long this will take.

#7

Yes, thanks for making that clear Gregory. I pointed to the YouCat image and source documentation because that one is the most “out of the box ready” in OpenCADC. When we do upstream the RSP TAP, it will also be in the form of a configurable image, and will come with those extra DataLink features.
I should also point out that YouCat is simply a TAP server but with the option feature of allowing end users to upload their own persistent tables. It’s an implementation of what will likely become the next TAP standard.
Also, when the RSP TAP is upstreamed, YouCat will inherit the DataLink service descriptor support as well.