Accessing the registry through TOPCAT
The use of TOPCAT is preferred.
In TOPCAT, click on VO Menu and select the TAP Query item.
In the TAP URL text box (bottom of the window) : http://voparis-rr.obspm.fr/tap -> Use Service.
Then it is possible to issue ADQL queries in the next page.
How to identify a TAP service
Previous (dirty) solution
Look for tables names ending with
This query returns 192 results, but there are duplication and redundant results. This query is thus not optimal.
Search for table
utypes old version (e.g.,
It is possible to filter on the EPNcore version. This helps to avoid out-dated services, but it could be problematic at the time of minor EPN-TAP version changes. This implies that providers must upgrade their resource regularly (as well as on clients). This is to be discussed.
A query including the EPNcore version would be one of the following:
This utype is deprecated.
With DaCHS 2, the utype of epn-tap services is filled automatically with the value 'ivo://ivoa.net/std/epntap#table-2.0'
A query matching all EPNcore versions would be:
which returns with 178 results at the time of writing.
For both examples, we retrieve in the same table the TAP access point (e.g.,
ivo://vopdc.obspm/tap/maser), as well as EPNcore services (e.g.,
ivo://vopdc.obspm/lesia/maser/expres/epn). The TAP servers must be removed. We can filter TAP access points out with the
Checking if services are correctly registered
Using the previous queries, including the filter to remove TAP endpoints, we get the following query:
We obtain 93 results:
Hints for clients
Retrieve the service infos:
Retrieve also the publisher/contact/creator/contributor: