http-server

sparq-http-server

sparq-server is a W3C-conformant HTTP server (axum/tokio) that exposes the sparq query engine over a sparq_core::Graph — in-memory by default, or durable on disk with --persist DIR (updates WAL-fsync'd, survive a restart with no rebuild; see the "Durability" gotcha). It implements the SPARQL 1.1 Protocol (query + update at /sparql) and the Graph Store HTTP Protocol (read + write), with Accept-driven content negotiation, hardening guards, Prometheus /metrics, WebSocket + SSE subscriptions, and opt-in grouped facet counts, prefix completion, time-travel, and GeoSPARQL.

Build with the default-off response-compression feature to negotiate gzip or zstd for outbound result bodies from Accept-Encoding. Compression is transport-transparent and streaming; SSE subscription responses and bodies that already have a Content-Encoding are left uncompressed:

cargo run -p sparq-server --features response-compression
curl --compressed -G http://127.0.0.1:3030/sparql \
  --data-urlencode 'query=SELECT * WHERE { ?s ?p ?o }'

Quickstart

Run the binary (server stack is the default-on server feature):

# serve a Turtle file on the default address 127.0.0.1:3030 (loopback — safe default)
cargo run -p sparq-server -- --format turtle data.ttl
# no data file => empty default graph (still answers queries, just no rows)
cargo run -p sparq-server
# custom bind addr / format (turtle | ntriples | nquads | trig). A NON-loopback bind
# (e.g. 0.0.0.0) is REFUSED unless --allow-remote / SPARQ_ALLOW_REMOTE=1 (no auth — see below).
cargo run -p sparq-server -- --addr 0.0.0.0:8080 --allow-remote --format ntriples data.nt

Opt-in HTTP/2 switches the TCP listener from its default HTTP/1.1-only builder to the hyper-util h1+h2 auto builder. With no certificate flags it accepts HTTP/1.1 and cleartext h2c; supplying both PEM paths enables TLS 1.3 with ALPN h2,http/1.1:

cargo run -p sparq-server --features http2 -- data.ttl \
  --tls-cert ./cert.pem --tls-key ./key.pem