RDF HDT (Header, Dictionary, Triples) library in Rust

Question

I would like to load RDF HDT (Header, Dictionary, Triples) files in a Rust application but haven't found any library that supports this. Before doing it myself or asking others to add it to their RDF libraries, I wanted to ask if there have been any existing efforts to load HDT with Rust.

Where I have unsuccessfully searched:

• https://www.rdfhdt.org and https://github.com/rdfhdt (mentions C++ and Java)
• https://crates.io/search?q=rdf%20hdt (only result is rdftk_io, which lists HDT under "TBD")
• https://github.com/oxigraph/rio

Updates

• I found an archived prototype HDT library at https://github.com/timplication/hdt-rs (update: now available anymore).
• a new implementation could use the front coder library available at https://crates.io/crates/fcsd
• https://crates.io/crates/terminus-store uses a format "based on HDT"

Answer 1

The hdt crate is a Rust library that allows loading existing HDT files in default format and querying using triple patterns. It has an adapter for the Sophia Rust RDF library, so that existing Sophia-based applications can load HDT files as well.

Explanation: The owner of https://github.com/timplication/hdt-rs (not available anymore) allowed me to build upon his now discontinued prototype. We currently have a paper about it on review in the Journal of Open Source Software (JOSS), read the current draft here.

API documentation is published at https://docs.rs/hdt/latest/hdt/.

Example usage from the docs:

use hdt::Hdt;
// Load an hdt file
let file = std::fs::File::open("example.hdt").expect("error opening file");
let hdt = Hdt::new(std::io::BufReader::new(file)).expect("error loading HDT");
// query
let majors = hdt.triples_with_pattern(Some("http://dbpedia.org/resource/Leipzig"), Some("http://dbpedia.org/ontology/major"),None);
println!("{:?}", majors.collect::<Vec<_>>());