Crate pyshacl_turbo_engine 

SHACL engine. Unsupported SHACL features are explicit errors. Python is not involved in compilation, targeting, rules, or validation.

The diagram and example below describe the borrowed graph query foundation.

Borrowed SPARQL graph architecture

GraphRead is the storage boundary: it streams indexed quad matches, enumerates named graphs and checks graph existence. Implementations for an in-memory oxigraph::model::Dataset and an open oxigraph::store::Transaction preserve their graph contexts. Transaction reads include pending insertions and deletions.

UnionGraph optionally exposes distinct data triples in the default graph while preserving named contexts. OverlayGraph optionally adds a borrowed shapes union under a fresh named graph, including when shapes are empty. For SHACL, wrap the data union in the shapes overlay, in that order. Shapes stay outside the data union and remain available to queries through the reserved shapes graph name.

QueryGraph implements spareval::QueryableDataset for these borrowed sources. The existing SPARQL evaluator retains parsing, planning, joins, expressions and property paths. The adapter translates graph matching: an absent GraphRead graph filter includes all contexts, whereas a SPARQL wildcard graph pattern matches named graphs only. Named-graph metadata retains empty native and overlay graphs. Invalid subject, predicate or graph term kinds yield no matches.

A source must stay consistent while results are consumed. Rust lifetimes retain its borrow; temporary match terms need not outlive the returned stream. Read and metadata errors remain errors, including during lazy query-result iteration. The adapter preserves stored RDF terms; it cannot restore lexical forms already normalized by a backend.

The adapter and views do not copy the base dataset or collect all graph names. The evaluator’s query-dependent joins, sorting, aggregates and output can still consume memory. Transaction ownership and commit/rollback remain with the caller.

Integration status: these are public Rust building blocks. Complete transaction-backed SHACL validation and snapshot-free SHACL function callbacks still require adoption. Existing validate_store and expand_store APIs continue to use consistent dataset snapshots.

Query pending changes through the composed views

use pyshacl_turbo_engine::{OverlayGraph, QueryGraph, UnionGraph};
use pyshacl_turbo_engine::oxigraph::{
    model::{Dataset, NamedNode, Quad},
    sparql::{QueryResults, SparqlEvaluator},
    store::Store,
};

let store = Store::new()?;
let mut transaction = store.start_transaction()?;
transaction.insert(&Quad::new(
    NamedNode::new("urn:alice")?,
    NamedNode::new("urn:knows")?,
    NamedNode::new("urn:bob")?,
    NamedNode::new("urn:data")?,
));

{
    let shapes = Dataset::new();
    let data_union = UnionGraph::new(&transaction);
    let view = OverlayGraph::new(
        &data_union, &shapes, NamedNode::new("urn:shapes")?.into(),
    )?;
    let result = SparqlEvaluator::new()
        .parse_query("ASK { <urn:alice> <urn:knows> <urn:bob> }")?
        .on_queryable_dataset(QueryGraph::new(&view))
        .execute()?;
    assert!(matches!(result, QueryResults::Boolean(true)));
}

// Dropping the transaction aborts its pending changes.
drop(transaction);
assert!(store.is_empty()?);

Re-exports

pub use oxigraph;

Structs

CompiledShapes

Immutable compiled shapes and SPARQL queries; safe to share across validations.

Options

OverlayGraph

Add a separate named shapes graph without cloning or modifying the base. Shapes are projected from their union; their original contexts do not leak into the base dataset. The reserved graph exists even when shapes are empty.

QueryGraph

Evaluate SPARQL over the exact graph contexts exposed by a borrowed source. Compose union/overlay views explicitly before constructing this adapter. The adapter adds no default union, snapshots, or graph-name collections. See the crate architecture and runnable example.

RuleExpansion

UnionGraph

Expose the union as the default graph while preserving original named graphs. The source must remain consistent throughout a read, as a borrowed Dataset or native transaction does. A repeated exact match must select the same first quad; no sorted order is required.

ValidationReport

Enums

Error

Traits

GraphRead

A fallible stream of stored quads, with explicit graph matching.

Functions

engine_fingerprint

evaluate_query

Execute a query with SHACL functions declared in the supplied shapes graph.

infer

infer_into

Infer over the dataset union and put only new statements in the destination. Original graph contexts remain available to callers and report descriptions.

inoculate

parse_dataset

parse_graph

Preserve blank-node identities and literal spellings/types while parsing. Oxigraph Store would canonicalize terms; oxrdf Dataset retains exact terms.

parse_store_snapshot

Store APIs expose RDF 1.1 strings as explicit xsd:string to RDFLib callers. Their N-Quads writer abbreviates the datatype, so restore that adapter identity while parsing, without altering ordinary document/Graph input.

serialize_graph

store_quad

Type Aliases

Result