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valentinedwv / ioostech

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Representation of missing/unknown metadata #65

Open GoogleCodeExporter opened 9 years ago

GoogleCodeExporter commented 9 years ago 
It is not clear what to do when available metadata is insufficient to populate 
all fields in an IOOS SOS response, e.g. DescribeSensor: do not report the 
field, report it but leave it empty, or fill it with "UNKNOWN" value. For 
example, the 52N CeNCOOS implementation either completely drops a sponsor info 
classifier(DescribeSensor/network), or returns the classifier itself 
(XPath=/sml:SensorML/sml:member[1]/sml:System[1]/sml:classification[1]/sml:Class
ifierList[1]/sml:classifier[4]/sml:Term[1]/@definition) but does not provide 
any value (DescribeSensor/station).

I believe that in this case we should use "UNKNOWN" value to fill in the fields 
rather than just leave them empty; as far as I know, the ncSOS does exactly 
that.

Shane, however, holds another opinion: a lot of potentially unknown or 
inapplicable metadata attributes can bloat a response, so these fields should 
stay just empty.

We need to develop a general IOOS policy for that issue to make sure that 
various implementations treat it equally.

Original issue reported on code.google.com by noaa...@gmail.com on 10 Mar 2014 at 4:43

GoogleCodeExporter commented 9 years ago 
I don't too feel strongly about this, but I wonder if we need a convention here 
at all, or if clients should just check for the existence of the metadata 
field. Maybe the best thing to do would be to match the CF/ACDD/etc convention 
for netCDF attributes. In netCDF, if an attribute doesn't apply or has an 
unknown value, is the convention to omit that attribute entirely or to add it 
with an "UNKNOWN" value?

Original comment by sh...@axiomalaska.com on 10 Mar 2014 at 6:28