GeoNetwork target version

This plugin will work on version 4 (is 3.10.x or 3.12.x needed?)

Implementation rules

Associated resources

How-to link thumbnails?
How-to link online resources? protocols? https://www.w3.org/TR/vocab-dcat-2/#Property:distribution_access_url
dcat:Distribution can have spatial and temporal resolution, license, accessRights, ... so hard to make all those properties available using the associated resource panel

      <dcat:distribution xmlns:dc="http://purl.org/dc/elements/1.1/">
         <dcat:Distribution>
            <dcat:downloadURL>https://sdi.eea.europa.eu/data/67c0ccae-a6db-433a-9852-fdb09f1b3a8b</dcat:downloadURL>
            <dct:description>DUT#Direct download|ENG#|FRE#|GER#</dct:description>
            <dct:format>
               <skos:Concept>
                  <skos:prefLabel>WWW:LINK</skos:prefLabel>
               </skos:Concept>
            </dct:format>
         </dcat:Distribution>
      </dcat:distribution>

References: https://github.com/metadata101/dcat2/commit/0391e4cde14dce766043306ee4e2c9e38c8353db

Multilingual

Add similar support as ISO records:

dct:language "This property refers to a language used in the textual metadata describing titles, descriptions, etc. of the Datasets in the Catalogue. This property can be repeated if the metadata is provided in multiple languages."
The first dct:language is the main language
Do we store language as a @rdf:resource or using skos:Concept (like in dcat-ap1)?

<dct:language rdf:resource="http://id.loc.gov/vocabulary/iso639-2/eng"/>

      <dct:language>
         <skos:Concept>
            <rdf:type rdf:resource="http://purl.org/dc/terms/LinguisticSystem"/>
            <skos:prefLabel xml:lang="nl"/>
            <skos:prefLabel xml:lang="en"/>
            <skos:prefLabel xml:lang="fr"/>
            <skos:prefLabel xml:lang="de"/>
            <skos:inScheme rdf:resource="http://publications.europa.eu/resource/authority/language"/>
         </skos:Concept>
      </dct:language>

Translations Simple case is title:

<dct:title xml:lang="fre">DCAT Modèle</dct:title>
<dct:title xml:lang="eng">DCAT Template</dct:title>

      If main language is eng.
      Other language fre.

      <dcat:keyword xml:lang="eng">Water</dcat:keyword>
      <dcat:keyword xml:lang="fre">Eau</dcat:keyword>
      <dcat:keyword xml:lang="eng">Management plan</dcat:keyword>
      <dcat:keyword xml:lang="fre">Plan de gestion</dcat:keyword>
      <dcat:keyword xml:lang="eng">Well</dcat:keyword>
      fre is missing. Empty field is available.
      <dcat:keyword xml:lang="spa">Cuenca</dcat:keyword>
      main language eng is missing and spa not declared has other language. This is not supported.

      To retrieve multilingual element by group we assume that an
      element in the main language is defined first and then
      we collect translations by group.

     update-fixed-info cleanup the encoding and create empty elements when needed. (maybe use inflate?)

Thesaurus for fields

Which thesaurus to use for which fields? (https://github.com/metadata101/dcat-ap1.1/tree/master/src/main/plugin/dcat-ap/thesauri/theme) and how to optimally configure it.

element	codelist
dct:language	http://publications.europa.eu/resource/authority/language / http://id.loc.gov/vocabulary/iso639-1
dct:license	https://spdx.org/licenses/
dct:accessRights	http://publications.europa.eu/resource/authority/access-right
dct:accrualPeriodicity	http://publications.europa.eu/resource/authority/frequency / http://purl.org/linked-data/sdmx/2009/code#freq-W
dct:conformsTo	http://www.opengis.net/def/crs / https://eur-lex.europa.eu/eli/reg / http://www.opengis.net/def/serviceType/ogc
dct:format / dcat:mediaType	https://www.iana.org/assignments/media-types

A concept value is preferably referenced as:

<dct:conformsTo rdf:resource="http://www.opengis.net/def/serviceType/ogc/wfs/2.0.0"/>

Although we also see implementations where the concept is (re)defined within the element

<dct:conformsTo> 
  <skos:Concept rdf:about="http://www.opengis.net/def/serviceType/ogc/wfs/2.0.0">
  <dct:title>OGC Web Feature Service</dct:title>
  </skos:Concept>
</dct:conformsTo>

Both situation may occur alongside each other, especially when indexing remote content.

I/O

What format to import? RDF4J library can ingest a number of formats and transform to rdf/xml.
...

GeoNetwork tasks

[x] Index DC multilingual https://github.com/geonetwork/core-geonetwork/pull/4863
[x] Language is encoded with a URL https://github.com/geonetwork/core-geonetwork/pull/4874
[x] Use date-picker directive for an attribute https://github.com/geonetwork/core-geonetwork/pull/4873 eg.

    <for name="dct:language/@rdf:resource" use="data-gn-language-picker">
      <directiveAttributes data-prefix="http://id.loc.gov/vocabulary/iso639-1/"/>
    </for>

[ ] Simple keyword editing https://github.com/geonetwork/core-geonetwork/pull/5577

Plugin tasks

Plugin

[x] DCAT2 XSD
- [ ] Should we set an order for elements? eg. dc:title first ? Maybe make it more meaningful for advanced view which is XSD driven. To check in https://github.com/metadata101/dcat2/blob/master/src/main/plugin/dcat2/update-fixed-info.xsl#L152-L208
- [ ] Cardinality (check rules in EU DCAT AP)
[x] DCAT2 Plugin initial config
[ ] DCAT2 Basic editor

IO

[ ] From/To 19139
[ ] From/To 19115-3
[ ] From/To RDF/XML
[ ] From/To JSONLD (schema.org and/or dcat)
[ ] From GeoDCAT-AP

Editor

[x] Editor / Date with calendar https://github.com/metadata101/dcat2/commit/8fa804d2c8f2e05c9cc47606cf18aefae16592c4
[x] Editor / Use thesaurus
[x] Editor / Multilingual https://github.com/metadata101/dcat2/commit/03838e9d59797e99ced3138b9bcbd9ade99c5085#diff-de87240753e226691bcec27aa3618bbaR222
[ ] Editor / Spatial part
[x] Editor / Add associated resources https://github.com/metadata101/dcat2/commit/0391e4cde14dce766043306ee4e2c9e38c8353db
[ ] CSW
[ ] Directory for contact see vcard:Kind and license
- Do we have to handle a mix of schema ? eg. directory in ISO and record in ISO + DCAT
[ ] Record link see rdf:Resource
[ ] Validation
- [ ] Schematron / Which rules applies? Not multilingual in dcat1 plugin.

Record view

[ ] XSL formatter & angular view
[ ] i18n (english)
[ ] Thesaurus list ?

Profiles

[ ] DCAT-AP-2.0.1

metadata101 / dcat2

Tasks list #1