MNT: Have a plan to retire vo_conesearch

[pllim]

At Astropy Coordination Meeting 2021, @tomdonaldson mentioned a desire to replace vo_conesearch with something else (probably with something in pyvo?). We need to formulate a transition plan with a timeline.

[bsipocz]

Would you have that something else in astroquery or rather a "how-to" for using pyvo for doing cone search?

[tomdonaldson]

Since pyvo already supports doing a VO standard cone search, this may mostly be an exercise in clearly documenting the alternative approach in the vo_conesearch documentation, then deprecating vo_conesearch. I want to look more carefully at what value-added features vo_conesearch offers to see if there are things that should be added to pyvo.

Based on the decisions we've had before regarding VO image searches and TAP searches, I think it is most consistent for the generic cone search capability to live in pyvo. Then, as with TAP, if an astroquery API for a specific resource wants to utilize that feature, it can.

[pllim]

In the spirit of PEP 20, "There should be one-- and preferably only one --obvious way to do it," I agree with you that PyVO should be the true home of cone search, and will be happy to work with you to make that happen. We can start with documentation, but I still want a path towards deprecation and eventual removal.

Besides the API here, I do keep a daily cron job to vet select services but I am really not sure if anyone is even using it.

TBH, vo_conesearch is at the "if it ain't broken, don't fix it" stage, as I am not really getting paid to maintain it anymore.

[bsipocz]

@tomdonaldson and @pllim - Would be nice to deprecate the module in favour of pyvo in the next release (coming out in the next few months or so), so we can actually remove it sometimes in the future. What do you think? Is there a plug-and-play tutorial or similar that can be linked-to in the docs as an alternative?

[pllim]

I will be happy to help but pyvo devs need to take the lead on this. I have not been involved in VO stuff for years. I just pop in once in a while to put out fires. 😬

[bsipocz]

I'll cross open an issue in pyvo, too.