[DAS] categorize

Andy Jenkinson andy.jenkinson at ebi.ac.uk
Tue Aug 31 16:15:33 UTC 2010

Hi list,

One of the (hopefully final) questions over the 1.6 specification concerns the "categorize" parameter in the features request. In DAS 1.53, this parameter is optional and may be either "yes" or "no". The default value is "no". The purpose is to instruct the server as to whether it must include in its response the optional "category" attribute of the <TYPE> element. However in practice, I believe most servers actually ignore this parameter and always include category information if it is available. If it is not available, servers cannot satisfactorily comply with a "categorize=yes" request and generally always provide an empty category attribute.

In current drafts of 1.6, the category attribute remains optional but the categorize parameter has its default reversed (that is, it matches what servers currently do, and a request to specifically remove the category from the response can more easily be honoured by core server software. However, it is apparent that the functionality offered by the categorize parameter is really rather limited. Its only real purpose in this form is to reduce the volume of the response. In addition, given the introduction of the ontology and expansion of DAS to more diverse domains, the category itself is becoming less important. If, for example, the ontology cvIds become mandatory in the next version of the specification, we could feasibly deprecate it.

So, it has been proposed that the categorize parameter be deprecated in 1.6, with a view to also deprecating the category attribute if and when ontology support becomes mandatory. Does anyone have any objections?


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