NFDI4Objects Graph

Technical architecture and documentation of the NFDI4Objects Knowledge Graph

Components

• n4o-fuseki: RDF triple store
• n4o-graph-apis: web interface and public SPARQL endpoint
• n4o-graph-importer: scripts to import data into the triple store
• lido-rdf-converter: convert LIDO format to RDF

Data flow

graph TD
    terminologies(terminologies) --> receive
    mappings(mappings) --> receive
    collections(collections) --> receive
    data(research data) --> receive
    stage(stage)

    subgraph importer ["n4o-graph-**importer**"]
        receive[**receive**]
        receive -- validate, transform, report --> stage
        stage --> load
        load[**load**]
    end
    subgraph "n4o-**fuseki**"
        kg(triple store)
    end
    subgraph "n4o-graph-**apis**"
        ui[**web application**]
    end
    subgraph "lido-rdf-**converter**"
        lido2rdf[**lido2rdf**]
        web-app[**web-app**]
    end

    stage --> ui
    kg -- SPARQL --> ui
    ui -- SPARQL --> apps(applications)

    receive <--> lido2rdf
    load -- SPARQL update & graph store --> kg

    web-app <--> ui

    ui <--web browser--> users(users)

Loading

Installation

Clone this repository or copy file docker-compose.yml and config file config-apis.yml to a local directory. Then start a new set of docker containers that make the N4O Knowledge Graph:

docker compose up --force-recreate --remove-orphans -V

To update the locally cached Docker images, first run:

docker compose pull

Usage

The web interface is made public at http://localhost:8000/ by default.

For importing data see n4o-graph-importer.

Configuration

The following environment variables can be used for configuration:

• PORT - port to publish n4o-graph-apis (public read access)
• IMPORT - port to publish n4o-graph-importer (with write access!)
• STAGE - stage directory (default: ./stage)
• DATA - data directory (optional, default: ./data)

Manual

Das Handbuch zum Knowledge Graphen ist mit quarto erstellt. Die Quelldateien liegen im Verzeichnis manual.

Die HTML-Version des Handbuch kann lokal mit make docs im Wurzelverzeichnis aktualisiert werden und liegt anschließend im Verzeichnis docs. Die publizierte Version unter https://nfdi4objects.github.io/n4o-graph/ wird bei GitHub automatisch aus dem main Branch erzeugt.

License

The content of this repository can be used freely as Public Domain (CC Zero).