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Review and repair the VO query pages

The VO query pages need a detailed review of all the issues and a plan for fixing them.

Example issues:

Remove hard coded limits from VO queries

https://git.astron.nl/astron-sdc/esap-api-gateway/-/blob/master/esap/query/api/services/ivoa.py#L171-L177

The VO query page mixes up the general IVOA registry with four specific protocols (TAP, SIA, SSA, and SCS).

  • "Query this dataset" button should be "Query the registry"
  • "Query this dataset" button should be "Query [TAP|SIA|SSA|SCS] services"

The description for the 'VO registry' is wrong - it describes the TAP protocol.

The 'documentation' link for the 'VO registry' actually points ot a registry instance.

The title for SSA says 'Table Access Protocol (SSA)'

The text for SSA has way too much detail.

Selecting [Query this dataset] for the 'VO registry'. Using the default keyword 'apertif' we get 1 TAP service at Astron. If we change the keyword to '2mass' we get 6 TAP services, including GAVO.

Select [x] 'GAVO DC TAP' and [Query selected VO Resources]

The table metadata reveals details of the JSON structure which are not relevant to the science user.

The first element shows the service URL and the number of 'keys'.

http://dc.zah.uni-heidelberg.de/tap => 30 keys

  • The URL is not useful to a science user, we should display the service name 'GAV TAP service'

  • The text '30 keys' should be '30 catalogs'

  • The number '30' is truncated, the GAV data center has 110 catalogs.

  • The metadata tree reveals details of the raw JSON response

    gaia: 3 keys
        fields: 27 keys
            source_id 4 keys
                name
                description
                units
                datatype

should be displayed as

    gaia: 3 tables
        27 columns
            source_id
                name
                description
                units
                datatype

The default query is:

    SELECT TOP 100 * from ivoa.obscore WHERE obs_collection='apertif-dr1' and dataproduct_subtype='continuum'

This instance happens to have 'ivoa.obscore', but the obs_collection and dataproduct_subtype are not relevant.

Changing to a simpler query

    SELECT TOP 100 * from ivoa.obscore

Select first two items from first page

ppakm31/data/PPAK_M31_F5_Ha6563.fits
ppakm31/data/PPAK_M31_F5_SII6730.fits

Select second page Get the same set of results as the first page

Check the contents of our shopping basket Source (archive) listed as 'vo_reg' when it should be the GAVO data center. The record is just an array of values, no metadata. Not even the original column names.

    {
    "archive":"vo_reg",
    "record":[
        "image",
        "",
        "2",
        "PPAKM31",
        "ppakm31/data/PPAK_M31_F5_Ha6563.fits",
        ....
        ....
        ]
    }

Once we have looked at our shopping basket, we can't get back to the query results. The [back] button goes back to the start of the VO reg query sequence, with default search terms.

Change the query to only select four columns

    SELECT TOP 100 obs_id, s_ra, s_dec, facility_name, preview from ivoa.obscore

Select 3rd and 4th rows Check the contents of our shopping basket The record is just an array of values, no metadata. Not even the original column names.

    {
    "archive":"vo_reg",
    "record":[
        "ppakm31/data/PPAK_M31_F5_SII6716.fits",
        "11.105143194205871",
        "41.626154777484786",
        "Calar Alto 3.5m telescope",
        "http://dc.zah.uni-heidelberg.de/getproduct/ppakm31/data/PPAK_M31_F5_SII6716.fits?preview=True"
        ]
    }

Change the query to select different columns

    SELECT TOP 100 s_fov, s_region from ivoa.obscore
    KeyError: "Got KeyError when attempting to get a value for field `thumbnail` on serializer
    `CreateAndRunQuerySerializer`.\nThe serializer field might be named incorrectly and not match
    any attribute or key on the `dict` instance.\nOriginal exception text was: 'thumbnail'."

Seems that a thumbnail (preview) column is required or the parser fails.

Back to the first page of VO query, and select 'Simple Image Access (SIA)'

[Query this dataset] jumps to IVOA query page, with ServiceType set to 'TAP: Tables' not 'SIA: Images'

Manually select 'SIA: Images'and change keyword to '2mass'. Results show 9 rows

Select the first row '2MASS All-Sky Atlas Image Service' and [Query selected service]

  • Metadata query fails to complete
  • Page fails to load ...
Edited by Dave M