README.md

veld_chain__gutenberg_triplestore

This repo contains chain velds encapsulating a gutenberg triplestore.

Project Gutenberg doesn't offer a native API and the only existing third-party API ( https://gutendex.com/ ) works just on a superficial level.

However, Project Gutenberg offers its entire metadata as a RDF/XML download: https://gutenberg.org/cache/epub/feeds/rdf-files.tar.bz2 .

This repo uses that RDF/XML metadata and ingests it into an Apache Fuseki triplestore, for arbitrarily complex sparql queries. As such, it can be used for linear workflows where gutenberg data must be queried in a structured and reproducible way, or it can be adapted into a centralized triplestore index for arbitrary remote clients.

All the steps, from download to ingest to querying, are encapsulated as chain velds, reusing these separate code velds:

• https://github.com/veldhub/veld_code__downloader
• https://github.com/veldhub/veld_code__apache_jena_fuseki

requirements

• git
• docker compose (note: older docker compose versions require running docker-compose instead of docker compose)

Clone this repo with all its submodules

git clone --recurse-submodules https://github.com/veldhub/veld_chain__gutenberg_triplestore.git

how to reproduce

Execute the following steps sequentially. See inside their respective VELD yaml files for more details.

./veld_download_gutenberg_metadata.yaml

Downloads the aforementioned metadata and extracts it to ./data/gutenberg_rdf/.

docker compose -f veld_download_gutenberg_metadata.yaml up

./veld_run_server.yaml

Runs an Apache Fuseki Triplestore server, which can be reached at http://localhost:3030/ . Its configuration is stored in ./data/fuseki_config/ and its data at ./data/fuseki_data/ . Important: leave this service running while executing the next chains!

docker compose -f veld_run_server.yaml up

./veld_import_rdf.yaml

Imports the extracted RDF data from the previous step into the triplestore. Note: this takes a while (on a AMD Ryzen 7 4800H, 32 GB RAM, it takes roughly 11 hours)

docker compose -f veld_import_rdf.yaml up

./veld_export.yaml

Exports data given rq (sparql query) files (samples can be found in ./data/queries/) into supported serializations which are saved into ./data/fuseki_export/

docker compose -f veld_export.yaml up