[Geoserver-devel] GetFeatureInfo on raster with nodata

GeoServer GeoServer Developer
1

Hi,
today I found that GetFeatureInfo on pixels with a nodata value returns the underlying pixel value (where a GetMap returns a transparent pixel).
I would have expected (to be consistent with vector data behaviour) to have an empty recordset as the result.
Talking with Daniele Romagnoli, I discovered that a parameter called EXCLUDE_NODATA_RESULT=true exists to return a different beast, the recordset is not empty but the real value is replaced with null. This is not working fully, indeed, because with an xml based output we get NaN and with json we get an error from the encoder.

My question is: would be returning an empty recordset by default better in this case?
Opinions are welcomed.

···

Regards,

Mauro Bartolomeoli

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Dott. Mauro Bartolomeoli
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2

Hi Mauro,
The initial implementation was part of the NCWMS use case.
With that flag being set, it was indeed returning nothing when finding a nodata pixel.
Then it has been refined returning NaN, to signal that raster data existed in the timeseries but was nodata, to differentiate it with cases of missing raster data at all (i.e. missing granule for that datetime).

We can revisit that by having a default behavior of returning null and eventually rename that vendor parameter to something else.

Daniele

···

Regards,
Daniele Romagnoli

GeoServer Professional Services from the experts! Visit http://goo.gl/it488V for more information.

Ing. Daniele Romagnoli
Senior Software Engineer

GeoSolutions S.A.S.
Via di Montramito 3/A
55054 Massarosa (LU)
Italy
phone: +39 0584 962313
fax: +39 0584 1660272

http://www.geo-solutions.it
http://twitter.com/geosolutions_it

Con riferimento alla normativa sul trattamento dei dati personali (Reg. UE 2016/679 - Regolamento generale sulla protezione dei dati “GDPR”), si precisa che ogni circostanza inerente alla presente email (il suo contenuto, gli eventuali allegati, etc.) è un dato la cui conoscenza è riservata al/i solo/i destinatario/i indicati dallo scrivente. Se il messaggio Le è giunto per errore, è tenuta/o a cancellarlo, ogni altra operazione è illecita. Le sarei comunque grato se potesse darmene notizia.

This email is intended only for the person or entity to which it is addressed and may contain information that is privileged, confidential or otherwise protected from disclosure. We remind that - as provided by European Regulation 2016/679 “GDPR” - copying, dissemination or use of this e-mail or the information herein by anyone other than the intended recipient is prohibited. If you have received this email by mistake, please notify us immediately by telephone or e-mail.