Hello Martin
Thank you for your very helpful information and guidance. I will be able
to continue with the work now, using the [2] document.
Kind regards
Rob
On 01/06/2017 12:14, Martin Desruisseaux wrote:
Hello Rob
No problem, Indeed I noticed that some of the links we have in SIS are
now obsolete and need to be updated. One useful link is the "ACDD
mapping" page at [1]. That page has a red warning about being outdated,
but I didn't found a better reference (except digging in their source
code). There is a XSLT file at [2] which may be more up to date, but it
is more difficult to read.
For validating our NetCDF to ISO 19115 mapping, we can use the
"Attribute" and "ISO 19115-2" columns of [1]. For example for the
"title" NetCDF attribute, [1] gives us:
/gmi:MI_Metadata/gmd:identificationInfo/gmd:MD_DataIdentification/gmd:citation/gmd:CI_Citation/gmd:title/gco:CharacterString
We ignore the XML prefixes (gmi:, gml:, etc.) and keep only the
identifiers beginning with a lower-case letter (the other ones are
redundant for us; the exists only because of particularities of the XML
schema used for those metadata). So for us, the above line is simplified as:
/identificationInfo/citation/title
We can compare with the "Path to ISO 19115" element documented in Apache
SIS for the AttributeNames.TITLE property [3]. It should be the same,
ignoring the "Metadata" root. If there is discrepancies, we would need
to list them for fixing them.
Instead of comparing with [1], which may be outdated, we may compare
directly with [2]. Taking again the example of the "title" property, we
can search "$title" in that page. We find it under the following tree:
<gmd:identificationInfo>
<xsl:element name="srv:SV_ServiceIdentification">
<xsl:attribute name="id">
<xsl:value-of select="$serviceID"/>
</xsl:attribute>
<gmd:citation>
<gmd:CI_Citation>
<gmd:title>
<xsl:call-template name="writeCharacterString">
<xsl:with-param name="stringToWrite" select="$title[1]"/>
</xsl:call-template>
</gmd:title>
... etc...
Ignoring all the XSL stuff and keeping only the element starting with a
lower case, we get again:
<gmd:identificationInfo>
<gmd:citation>
<gmd:title>
... etc...
which can be compared with the above-cited "Path to ISO 19115"
documented in SIS. We could also take this opportunity for listing new
ACDD elements that are not yet in SIS.
Just in case it may be useful, NOAA is a good source of documentation
about using ISO 19115 for geoscience. For example the ISO 19115 Core
Elements page [4] may be a starting point for familiarizing with ISO
19115. That standard is the pivot metadata model in Apache SIS. No
matter which file format we read (NetCDF, Landsat, GeoTIFF, etc.), we
map to ISO 19115 so we can work on only one metadata model.
Regards,
Martin
[1]
http://wiki.esipfed.org/index.php/Attribute_Convention_for_Data_Discovery_(ACDD)_Mappings
[2] https://ngdc.noaa.gov/metadata/published/xsl/nciso2.0/UnidataDD2MI.xsl
[3]
http://sis.apache.org/apidocs/org/apache/sis/storage/netcdf/AttributeNames.html#TITLE
[4] https://geo-ide.noaa.gov/wiki/index.php?title=ISO_19115_Core_Elements
Le 01/06/2017 à 12:37, Rob Wallace a écrit :
I'm sorry, I cannot locate the ncISO XSLT file required for the path
matching. The link:
https://geo-ide.noaa.gov/wiki/index.php?title=NcISO
does get me to an NcISO page, but I'm lost thereafter. There are
remarks on some of the pages that things have been moved. This may be
my problem?
