Contexts¶

DRAFT Specification / Work in Progress

This portion of the BTAA GIN site, our GeoBTAA API, and our Linked Data offerings are a WORK IN PROGRESS. Please reach out if you have questions or wish to participate in bringing these resources to public release.

JSON-LD contexts provide mappings between terms used in JSON documents and IRIs. They are essential for creating interoperable linked data and ensuring consistent data interpretation across different systems.

Overview¶

Contexts in this repository define:

Term mappings: Short names for IRIs used in metadata records
Type coercions: Automatic type conversion for dates, booleans, and other data types
Container specifications: How arrays and sets should be handled
Namespace prefixes: Short prefixes for common vocabularies and ontologies

Available Contexts¶

BTAA Aardvark Context¶

The primary context for GeoBTAA metadata records, extending the OpenGeoMetadata Aardvark schema with BTAA-specific elements.

File: contexts/ogm-aardvark-btaa.context.jsonld

This context provides mappings for:

Core Aardvark Elements¶

Identifiers: id_ → dct:identifier
Titles & Descriptions: dct_title_s, dct_alternative_sm, dct_description_sm
Agents: dct_creator_sm, dct_publisher_sm, schema_provider_s
Subjects & Keywords: dct_subject_sm, dcat_keyword_sm
Languages: dct_language_sm

Resource Classification¶

Resource Types: gbl_resourceClass_sm, gbl_resourceType_sm
Formats & Themes: dct_format_s, dcat_theme_sm

Temporal Coverage¶

Temporal: dct_temporal_sm, gbl_indexYear_im, gbl_dateRange_drsim

Spatial Coverage¶

Spatial: dct_spatial_sm
Geometry: locn_geometry (WKT), dcat_bbox, dcat_centroid

Relationships¶

Part/Whole: dct_ispartof_sm, pcdm_memberOf_sm
Versions: dct_isVersionOf_sm, dct_replaces_sm, dct_isReplacedBy_sm
Sources: dct_source_sm, dct_relation_sm

Rights & Access¶

Rights: dct_rights_sm, dct_license_sm, dct_rightsHolder_sm
Access: dct_accessRights_s

BTAA Custom Elements¶

Institutional: b1g_code_s, b1g_status_s, b1g_publication_state_s
Dates: b1g_dateAccessioned_s, b1g_dateRetired_s
Accrual: b1g_dct_accrualMethod_s, b1g_dct_accrualPeriodicity_s
Access Control: b1g_access_s (JSON map), b1g_child_record_b
Geographic: b1g_geonames_sm (URIs), b1g_dcat_spatialResolutionInMeters_sm
Administrative: b1g_adminTags_sm, b1g_dct_provenanceStatement_sm

OGM UI Context¶

A specialized context for OpenGeoMetadata UI components and viewer integrations.

File: contexts/ogm-ui.context.jsonld

This context provides mappings for:

UI Components: ui, citation, viewer
Protocols: protocol
Endpoints: endpoint (typed as IRI)
Geometry: geometry (typed as JSON)

Usage¶

Including Contexts in Metadata Records¶

{
  "@context": "https://gin.btaa.org/ld/contexts/ogm-aardvark-btaa.context.jsonld",
  "@type": "Dataset",
  "dct_title_s": "Example Geospatial Dataset",
  "dct_creator_sm": ["University of Example"],
  "dct_spatial_sm": ["United States"],
  "b1g_code_s": "EXAMPLE"
}

Using Multiple Contexts¶

{
  "@context": [
    "https://raw.githubusercontent.com/geobtaa/ld/main/contexts/btaa-aardvark.context.jsonld",
    "https://raw.githubusercontent.com/geobtaa/ld/main/contexts/ogm-ui.context.jsonld"
  ],
  "@type": "Dataset",
  "dct_title_s": "Example Dataset",
  "viewer": {
    "protocol": "wms",
    "endpoint": "https://example.org/geoserver/wms"
  }
}

Namespace Prefixes¶

The contexts include mappings for these common vocabularies:

dct: Dublin Core Terms (http://purl.org/dc/terms/)
dcat: Data Catalog Vocabulary (http://www.w3.org/ns/dcat#)
schema: Schema.org (https://schema.org/)
gsp: GeoSPARQL (http://www.opengis.net/ont/geosparql#)
gbl: GeoBlacklight (https://geo.blacklight.org/terms#)
b1g: BTAA GIN (https://gin.btaa.org/terms/b1g#)
ogm: OpenGeoMetadata (https://opengeometadata.org/ogm/terms#)

Type Coercions¶

The contexts automatically handle type conversions:

Dates: xsd:date for accessioned/retired dates
DateTimes: xsd:dateTime for modification timestamps
Booleans: xsd:boolean for flags like georeferenced, suppressed
Decimals: xsd:decimal for spatial resolution values
JSON: @json for complex objects like references and access maps
IRIs: @id for URIs and identifiers

Container Specifications¶

Sets: @container: @set for multi-valued properties
Arrays: Standard JSON arrays for ordered collections
Language Maps: Automatic language tagging for internationalized content

Contexts - JSON-LD context definitions
Profiles - Profile specifications and constraints
Schemas - JSON Schema validation