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DCAT-AP for Switzerland format

The ‹Open Government Data› project organisation have worked out a joint solution for metadata. The portal opendata.swiss implements these standards - see Publish on opendata.swiss.

Have a look at the following file for a quickstart: full dataset example (RDF)

Namespaces

<rdf:RDF
  xmlns:dct="http://purl.org/dc/terms/"
  xmlns:dc="http://purl.org/dc/elements/1.1/"
  xmlns:dcat="http://www.w3.org/ns/dcat#"
  xmlns:foaf="http://xmlns.com/foaf/0.1/"
  xmlns:xsd="http://www.w3.org/2001/XMLSchema#"
  xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
  xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
  xmlns:vcard="http://www.w3.org/2006/vcard/ns#"
  xmlns:odrs="http://schema.theodi.org/odrs#"
  xmlns:schema="http://schema.org/">

Internationalisation

The DCAT-AP for Switzerland Standard expects that text elements of the datasets and their distributions be translated in the following four languages: French (fr) German (de) Italian (it) English (en)

The multi-lingual elements have to contain the xml:lang attribute, as the following example show:

<dct:title xml:lang="fr">FR Titre</dct:title>
<dct:title xml:lang="de">DE Titel</dct:title>
<dct:title xml:lang="it">IT Titolo</dct:title>
<dct:title xml:lang="en">EN Title</dct:title>

DCAT-AP reference documentation

Definition of dcat:Catalog
Content Contains nested elements of type <dcat:dataset>
Mandatory yes
Cardinality 1..1
Attributes
Description Catalog with datasets

Example:

<dcat:Catalog>
    <dcat:dataset>
        [...]
    </dcat:dataset>
    [further dcat:dataset]
</dcat:Catalog>
dcat:dataset
Content Contains single nested element of type dcat:Dataset. See Definition of dcat:Dataset.
Mandatory yes
Cardinality 1..n
Attributes
Description Wrapper for a dataset of the catalog

Example:

<dcat:dataset>
    <dcat:Dataset rdf:about="http://swisstopo/325">
        [Content of dataset]
    </dcat:Dataset>
</dcat:dataset>
[further dcat:dataset]

Definition of dcat:Dataset
Mandatory yes
Cardinality 1..1
Attributes Name rdf:about
Content Unique identifier for dataset
Mandatory yes
Description A single dataset of the catalog

Example:

<dcat:Dataset rdf:about="http://swisstopo/325">
    [Content of dataset]
</dcat:Dataset>
dct:identifier
Type rdfs:Literal http://www.w3.org/TR/rdf-schema/#ch_literal
Mandatory yes
Cardinality 1..1
Description Unique identifier of the dataset across all publishers. A good way to make sure this identifier is unique is to link the source system ID with the ID of the publisher: [Source-Dataset-ID]@[Source-Organisation-ID]. It is recommended that the identifier consists out of the following characters: A-Za-z, 0-9 without special characters, except - and _

Example:

<dct:identifier>325@swisstopo</dct:identifier>
dct:title
Type rdfs:Literal http://www.w3.org/TR/rdf-schema/#ch_literal
Mandatory yes
Cardinality 1..n (one for each language)
Attributes Name xml:lang
Content en, de, fr, it
Description Language of the element
Mandatory yes
Description Title of the dataset in the language defined by the xml:lang attribute

Example:

<dct:title xml:lang="de">Eisenbahnlärm Nacht</dct:title>
dct:description
Type rdfs:Literal http://www.w3.org/TR/rdf-schema/#ch_literal
Mandatory yes - in all the languages in which distributions are available
Cardinality 1..n (one for each language)
Attributes Name xml:lang
Content en, de, fr, it
Description Language of the element
Mandatory yes
Description Description of the dataset in the language defined by the xml:lang attribute

Example:

<dct:description xml:lang="de">Die Karte zeigt, welcher Lärmbelastung die Bevölkerung durch den Schienenverkehr ausgesetzt ist.</dct:description>
dct:issued
Type Date and time in ISO-8601 format
Mandatory Can be left out if there is no distribution
Cardinality 0..1
Attributes Name rdf:datatype
Content http://www.w3.org/2001/XMLSchema#dateTime
Description Type of the field
Mandatory yes
Description Date of the first publication of this dataset. If this date is unknown, the date of the first publication on opendata.swiss can be used. If that date is in the future, the dataset is not displayed.

Example:

<dct:issued rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime"> 2013-04-26T01:00:00Z</dct:issued>
dct:modified
Type Date and time in ISO-8601 format
Mandatory Only when the dataset has changed since the first publication
Cardinality 0..1
Attributes Name rdf:datatype
Content http://www.w3.org/2001/XMLSchema#dateTime
Description Type of the field
Mandatory yes
Description Date of the last change (since the first publication on opendata.swiss)

Example:

<dct:modified rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime"> 2013-04-26T01:00:00Z</dct:modified>
dct:publisher
Elements rdf:Description
Type Nested element
Mandatory yes
Cardinality 1..n
Description The publishers of the dataset. rdf:about is an optional attribute.

Example:

<dct:publisher>
    <rdf:Description rdf:about="https://www.bafu.admin.ch/">
        <rdfs:label>Bundesamt für Landestopografie swisstopo</rdfs:label>
    </rdf:Description>
</dct:publisher>
dct:contactPoint
Elements vcard:Organization
Type vcard:Kind
Mandatory yes
Cardinality 1..n
Description One or more contact email addresses for this dataset vcard:fn. Description of the point of contact vcard:hasEmail has an attribute rdf:resource which contains the email of the point of contact (including mailto:)

Example:

<dcat:contactPoint>
    <vcard:Organization>
        <vcard:fn>Abteilung Lärm BAFU</vcard:fn>
        <vcard:hasEmail rdf:resource="mailto:noise@bafu.admin.ch"/>
    </vcard:Organization>
</dcat:contactPoint>

<dcat:contactPoint>
    <vcard:Individual>
        <vcard:fn>Sekretariat BAFU</vcard:fn>
        <vcard:hasEmail rdf:resource="mailto:sekretariat@bafu.admin.ch"/>
    </vcard:Individual>
</dcat:contactPoint>
dct:theme
Type skos:Concept http://www.w3.org/2009/08/skos-reference/skos.html#Concept
Mandatory yes
Cardinality 1..n
Attributes Name rdf:resource
Description URI to the category
Mandatory yes
Description Categorisation of the data. In the rdf:resource attribute, the unique URI of the category from SKOS-RDF (RDF) must be given. The following values are accepted from Themes:
  • http://opendata.swiss/themes/work
  • http://opendata.swiss/themes/construction
  • http://opendata.swiss/themes/population
  • http://opendata.swiss/themes/education
  • http://opendata.swiss/themes/energy
  • http://opendata.swiss/themes/finances
  • http://opendata.swiss/themes/geography
  • http://opendata.swiss/themes/legislation
  • http://opendata.swiss/themes/health
  • http://opendata.swiss/themes/trade
  • http://opendata.swiss/themes/industry
  • http://opendata.swiss/themes/crime
  • http://opendata.swiss/themes/culture
  • http://opendata.swiss/themes/agriculture
  • http://opendata.swiss/themes/mobility
  • http://opendata.swiss/themes/public-order
  • http://opendata.swiss/themes/politics
  • http://opendata.swiss/themes/prices
  • http://opendata.swiss/themes/territory
  • http://opendata.swiss/themes/social-security
  • http://opendata.swiss/themes/statistical-basis
  • http://opendata.swiss/themes/tourism
  • http://opendata.swiss/themes/administration
  • http://opendata.swiss/themes/national-economy

Example:

<dcat:theme rdf:resource="http://opendata.swiss/themes/population"/>
dct:language
Type rdfs:Literal ISO 639-1 two-letter code
Content en, de, fr, it
Mandatory no
Cardinality 0..n (for each language)
Attributes
Description Should contain all languages for which a distribution is available. This field is not validated and is used for display purposes. If all distributions are language-independant, this field can be left out.

Example:

<dct:language>de</dct:language>
dct:relation
Elements rdf:Description
Type Nested element
Mandatory no
Cardinality 0..n
Description A relation to a document. The rdf:about must link to a related document.

Example:

<dct:relation>
    <rdf:Description rdf:about="http://www.bafu.admin.ch/laerm/index.html?lang=de">
        <rdfs:label>Webseite des BAFU</rdfs:label>
    </rdf:Description>
</dct:relation>
dcat:keyword
Type rdfs:Literal http://www.w3.org/TR/rdf-schema/#ch_literal
Mandatory no
Cardinality 0..n
Attributes Name xml:lang
Content en, de, fr, it
Description Language of the element
Mandatory yes
Description Keyword who describes this dataset

Example:

<dcat:keyword xml:lang="de">Nacht</dcat:keyword>
<dcat:keyword xml:lang="fr">Nuit</dcat:keyword>
<dcat:keyword xml:lang="it">Noche</dcat:keyword>
<dcat:keyword xml:lang="en">Night</dcat:keyword>
dcat:landingPage
Type foaf:Document http://xmlns.com/foaf/spec/#term_Document
Mandatory no
Cardinality 0..1
Attributes
Description Website of the dataset with related information

Example:

<dcat:landingPage>http://www.bafu.admin.ch/laerm/index.html?lang=de</dcat:landingPage>
dcat:spatial
Type dct:Location http://dublincore.org/documents/2012/06/14/dcmi-terms/?v=terms#Location
Mandatory no
Cardinality 0..n
Attributes
Description Geographical classification of the dataset. Can be a description, coordinates, a bounding-box or a polygon. This field currently supports GeoJSON with the LOCN extension.

Example:

<dct:spatial rdf:resource="http://publications.europa.eu/mdr/authority/country/ZWE"/>
<dct:spatial>Bern</dct:spatial>
<dct:spatial>
  <dct:Location>
    <locn:geometry rdf:datatype="https://www.iana.org/assignments/media-types/application/vnd.geo+json">
    <![CDATA[
      {
        "type":"Polygon",
        "crs":{"type":"name","properties":{"name":"urn:ogc:def:crs:OGC:1.3:CRS84"}},
        "coordinates":[[[-6.41736,55.7447],[2.05827,55.7447],[2.05827,49.8625],[-6.41736,49.8625],[-6.41736,55.7447]]]
      }
    ]]>
    </locn:geometry>
  </dct:Location>
</dct.spatial>

See also: How should dct:spatial and dct:Location be used?

dcat:coverage
Type dct:LocationPeriodOrJurisdiction http://dublincore.org/documents/2012/06/14/dcmi-terms/?v=terms#LocationPeriodOrJurisdiction
Mandatory no
Cardinality 0..n
Attributes
Description This field is currently not used, use dcat:spatial instead.

Example:

<dct:coverage/>
dcat:temporal
Type dct:PeriodOfTime http://dublincore.org/documents/2012/06/14/dcmi-terms/?v=terms#terms-PeriodOfTime
Mandatory no
Cardinality 0..n
Attributes
Description One or more time period(s) that cover the dataset. <schema:startDate> contains the start date, <schema:endDate> contains the end date format for dates: http://www.w3.org/2001/XMLSchema#date

Example:

<dct:temporal>
    <dct:PeriodOfTime>
        <schema:startDate rdf:datatype="http://www.w3.org/2001/XMLSchema#date">1905-03-01</schema:startDate>
        <schema:endDate rdf:datatype="http://www.w3.org/2001/XMLSchema#date">2013-01-05</schema:endDate>
    </dct:PeriodOfTime>
</dct:temporal>
dct:accrualPeriodicity
Mandatory no
Cardinality 0..n
Attributes Name rdf:resource
Type dct:Frequency
Mandatory yes
Description The frequency in which this dataset is updated. Values for dct:Frequency: http://dublincore.org/groups/collections/frequency/

Example:

<dct:accrualPeriodicity rdf:resource="http://purl.org/cld/freq/daily"/>
rdfs:seeAlso
Type rdfs:Literal http://www.w3.org/TR/rdf-schema/#ch_literal
Mandatory no
Cardinality 0..n
Attributes
Description Link to related datasets. Contains the identifier of the linked dataset.

Example:

<rdfs:seeAlso>326@swisstopo</rdfs:seeAlso>
dcat:distribution
Content Contains single nested element of type dcat:Distribution. See Definition of dcat:Distribution.
Mandatory yes
Cardinality 1..n
Attributes
Description Wrapper for a distribution of the dataset

Example:

<dcat:distribution>
    <dcat:Distribution rdf:about="http://swisstopo/325/ch.bafu.laerm-bahnlaerm_nacht">
        [Content of distribution]
    </dcat:Distribution>
</dcat:distribution>
[further distributions]

Definition of dcat:Distribution
Mandatory yes
Cardinality 1..1
Attributes Name rdf:about
Content Unique identifier for distribution
Mandatory yes
Description A single distribution of the dataset

Example:

<dcat:Distribution rdf:about="http://swisstopo/325/ch.bafu.laerm-bahnlaerm_nacht">
    [Content of distribution]
</dcat:Distribution>
dcat:identifier
Type rdfs:Literal http://www.w3.org/TR/rdf-schema/#ch_literal
Mandatory no
Cardinality 0..1
Attributes
Description Identifier of the distribution in the source system

Example:

<dct:identifier>ch.bafu.laerm-bahnlaerm_nacht</dct:identifier>
dcat:title
Type rdfs:Literal http://www.w3.org/TR/rdf-schema/#ch_literal
Mandatory no - except if the distribution does not contain all the content of the dataset.
Cardinality 0..n (one for each language)
Attributes Name xml:lang
Content en, de, fr, it
Description Language of the element
Mandatory yes
Description The title of the distribution in the language defined by the xml:lang? attribute. If this element is left out, the dct:title of the dataset is used instead.

Example:

<dct:title xml:lang="de">WMS (ch.bafu.laerm-bahnlaerm_nacht)</dct:title>
dct:description
Type rdfs:Literal http://www.w3.org/TR/rdf-schema/#ch_literal
Mandatory no - except if the distribution does not contain all the content of the dataset.
Cardinality 0..n (one for each language)
Attributes Name xml:lang
Content en, de, fr, it
Description Language of the element
Mandatory yes
Description Description of the distribution in the language defined by the xml:lang attribute

Example:

<dct:title xml:lang="de">WMS (ch.bafu.laerm-bahnlaerm_nacht)</dct:title>
dct:issued
Type Date and time in ISO-8601 format
Mandatory yes
Cardinality 1..1
Attributes Name rdf:datatype
Content http://www.w3.org/2001/XMLSchema#dateTime
Description Type of the field
Mandatory yes
Description Date of the publication of this distribution

Example:

<dct:issued rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime"> 2013-05-11T00:00:00Z</dct:issued>
dct:modified
Type Date and time in ISO-8601 format
Mandatory Only when the distribution has changed since the first publication. If this distribution was changed several times, this corresponds to the date of the latest change.
Cardinality 0..1
Attributes Name rdf:datatype
Content http://www.w3.org/2001/XMLSchema#dateTime
Description Type of the field
Mandatory yes
Description Date of the last change of the distribution

Example:

<dct:modified rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime"> 2015-04-26T00:00:00Z</dct:modified>
dct:language
Type rdfs:Literal ISO 639-1 two-letter code
Content en, de, fr, it
Mandatory no
Cardinality 0..n (for each language)
Attributes
Description Languages in which this distribution is available. If the distribution is language-independant, this can be left out.

Example:

<dct:language>de</dct:language>
dcat:accessURL
Type http://www.w3.org/2001/XMLSchema#anyURI
Mandatory yes
Cardinality 1..n
Attributes Name rdf:datatype
Content http://www.w3.org/2001/XMLSchema#anyURI
Description Type of the field
Mandatory yes
Description URL where the distribution can be found. This could be either a download URL, an API URL or a landing page URL. If the distribution is only available through a landing page, this field must contain the URL of the landing page. If a download URL was given for this distribution, this field has to contain the same value.

Example:

<dcat:accessURL rdf:datatype="http://www.w3.org/2001/XMLSchema#anyURI"> http://wms.geo.admin.ch/</dcat:accessURL>
dct:downloadURL
Type http://www.w3.org/2001/XMLSchema#anyURI
Mandatory no
Cardinality 0..n
Attributes Name rdf:datatype
Content http://www.w3.org/2001/XMLSchema#anyURI
Description Type of the field
Mandatory yes
Description URL of a data file, if the distribution can be downloaded. For each of these, a dcat:accessURL has to exist.

Example:

<dcat:downloadURL rdf:datatype="http://www.w3.org/2001/XMLSchema#anyURI"> http://data.geo.admin.ch.s3.amazonaws.com/ch.fill/data.zip</dcat:downloadURL>
dct:rights
Type rdfs:Literal http://www.w3.org/TR/rdf-schema/#ch_literal
Content Possible values:
  • NonCommercialAllowed-CommercialAllowed-ReferenceNotRequired (acceptable for opendata.swiss, Open Definition compliant)
  • NonCommercialAllowed-CommercialAllowed-ReferenceRequired (acceptable for opendata.swiss, Open Definition compliant)
  • NonCommercialAllowed-CommercialWithPermission-ReferenceNotRequired (acceptable for opendata.swiss)
  • NonCommercialAllowed-CommercialWithPermission-ReferenceRequired (acceptable for opendata.swiss)
  • NonCommercialAllowed-CommercialNotAllowed-ReferenceNotRequired (not acceptable for opendata.swiss)
  • NonCommercialAllowed-CommercialNotAllowed-ReferenceRequired (not acceptable for opendata.swiss)
  • NonCommercialNotAllowed-CommercialNotAllowed-ReferenceNotRequired (not acceptable for opendata.swiss)
  • NonCommercialNotAllowed-CommercialNotAllowed-ReferenceRequired (not acceptable for opendata.swiss)
  • NonCommercialNotAllowed-CommercialAllowed-ReferenceNotRequired (not acceptable for opendata.swiss)
  • NonCommercialNotAllowed-CommercialAllowed-ReferenceRequired (not acceptable for opendata.swiss)
  • NonCommercialNotAllowed-CommercialWithPermission-ReferenceNotRequired (not acceptable for opendata.swiss)
  • NonCommercialNotAllowed-CommercialWithPermission-ReferenceRequired (not acceptable for opendata.swiss)
Mandatory yes
Cardinality 1..1
Description Rights statement of this distribution. This is composed of 3 elements that can be summarized in a string literal: - Non-commercial use: allowed or not allowed - Commercial use: allowed, allowed with permission and not allowed - Reference: required or not required
Example: 
<dct:rights>NonCommercialAllowed-CommercialAllowed-ReferenceNotRequired</dct:rights>
dct:license
Type dct:LicenseDocument
Mandatory no
Cardinality 0..1
Attributes
Description Not used, see dct:rights. This field ensures compatibility to other metadata standards.

Example:

<dct:license/>
dct:byteSize
Type rdfs:Literal http://www.w3.org/TR/rdf-schema/#ch_literal
Mandatory no - except if the distribution is available as a data download (see downloadURL).
Cardinality 0..1
Attributes
Description Size of the data in bytes

Example:

<dcat:byteSize>1024</dcat:byteSize>
dct:mediaType
Type dct:MediaTypeOrExtent http://www.iana.org/assignments/media-types/media-types.xhtml
Mandatory no - except if the distribution is available as a data download (see downloadURL).
Cardinality 0..1
Attributes
Description This value will be used to display the ressource-format if the downloadURL is empty. Only values from the list of IANA MIME types http://www.iana.org/assignments/media-types/media-types.xhtml

Example:

<dcat:mediaType>text/html</dcat:mediaType>
dct:format
Type dct:MediaTypeOrExtent
Mandatory no
Cardinality 0..1
Attributes
Description If neither the downloadURL nor the mediaType provide a valid format this value is used to display the format of the ressource.

Example:

<dct:format/>
dct:coverage
Type dct:LocationPeriodOrJurisdiction http://dublincore.org/documents/2012/06/14/dcmi-terms/?v=terms#LocationPeriodOrJurisdiction
Mandatory no
Cardinality 0..n
Attributes
Description Distributions can be classified by their location or time period (for example, one for each canton, one for each year, etc.)

Example:

<dct:coverage/>

Common fields

rdf:Description
Type rdfs:label
Mandatory yes
Cardinality 1..1
Attributes Name rdf:about
Mandatory no
Description The description of the dataset/distribution

The following documents on the selection and definition of OGD standards for metadata are available in the Library: