- Title: Themes
- Identifier: https://stac-extensions.github.io/themes/v1.0.0/schema.json
- Field Name Prefix: -
- Scope: Item, Catalog, Collection
- Extension Maturity Classification: Proposal
- Owner: @emmanuelmathot @m-mohr
This document explains the Themes Extension to the SpatioTemporal Asset Catalog (STAC) specification.
This extension is meant to support knowledge organization systems used to classify the resource
(i.e. controlled vocabularies / keywords such as Geonames or Wikipedia).
If you just need "uncontrolled" free-form keywords / tags, please use the
keywords field instead.
This extension is based on the field themes as defined in OGC API - Records.
- Examples:
- Item example: Shows the basic usage of the extension in a STAC Item
- Collection example: Shows the basic usage of the extension in a STAC Collection
- JSON Schema
- Changelog
The fields in the table below can be used in these parts of STAC documents:
- Catalogs
- Collections
- Item Properties (incl. Summaries in Collections)
- Assets (for both Collections and Items, incl. Item Asset Definitions in Collections)
- Links
| Field Name | Type | Description |
|---|---|---|
| themes | [Theme Object] | REQUIRED. A knowledge organization system used to classify the STAC entity. Each element is a concept and their respective knowledge organization system / controlled vocabulary. |
The Theme Object aims at defining a normalized list of concepts based on a knowledge organization system / controlled vocabulary (e.g. geonames).
| Field Name | Type | Description |
|---|---|---|
| concepts | [Concept Object] | REQUIRED. One or more entity/concept identifers from this knowledge system. |
| scheme | string | REQUIRED. An identifier for the knowledge organization system used. It is recommended that the identifier is a resolvable URI. |
Describes an individual concept from the knowledge system.
| Field Name | Type | Description |
|---|---|---|
| id | string | REQUIRED. An identifier for the concept. |
| title | string | A human readable title for the concept. |
| description | string | A human readable description for the concept. |
| url | string | RECOMMENDED. A URI providing further description of the concept. |
All contributions are subject to the STAC Specification Code of Conduct. For contributions, please follow the STAC specification contributing guide Instructions for running tests are copied here for convenience.
The same checks that run as checks on PR's are part of the repository and can be run locally to verify that changes are valid.
To run tests locally, you'll need npm, which is a standard part of any node.js installation.
First you'll need to install everything with npm once. Just navigate to the root of this repository and on your command line run:
npm installThen to check markdown formatting and test the examples against the JSON schema, you can run:
npm testThis will spit out the same texts that you see online, and you can then go and fix your markdown or examples.
If the tests reveal formatting problems with the examples, you can fix them with:
npm run format-examples