Simple Cone Search version 1.03 Erratum 3

Author: Markus Demleitner

Date last changed: 2022-05-30

Date accepted: 2022-07-06

Rationale

The example error response given in version 1.03 of the cone search specification not only is severely outdated in some respects, it is also invalid VOTable, as it is missing a RESOURCE element, which has always been mandatory in VOTables. Since it is common for implementors to base their implementations on examples given in a specification, this may lead to confusion. This erratum replaces the outdated, invalid example with an example adhering to VOTable and giving the version 1 XML namespace for VOTable.

Since SCS offers several ways of communicating an error status, one might consider using the opportunity to better align SCS with DALI, which requires an INFO element in a RESOURCE. However, there is no way to satisfy both DALI and SCS at the same time. Hence, we refrain from changing the SCS preference of an INFO as a direct child of VOTable.

Erratum content

In SCS 1.03's a box with example error responses, replace:

<?xml version="1.0"?>
<!DOCTYPE VOTABLE SYSTEM "http://us-vo.org/xml/VOTable.dtd">
<VOTABLE version="1.0">
  <DESCRIPTION>MAST Simple Cone Search Service</DESCRIPTION>
  <INFO ID="Error" name="Error" value="Error in input RA value: as3f"/>
</VOTABLE>

with:

<VOTABLE xmlns="http://www.ivoa.net/xml/VOTable/v1.3">
  <INFO ID="Error" name="Error" 
    value="Field RA: 'as3f' is not a valid literal for RA"/>
  <RESOURCE/>
</VOTABLE>

Impact Assessment

No normative content is changed. Ideally, there will be somewhat less confusion among adopters.