Crate petgraph_decypher 

petgraph-decypher – build petgraph graphs from OpenCypher queries.

Overview

This crate provides three main entry points:

• parse_cypher – parse a Cypher query string into the internal query plan.
• build_graph_from_cypher – parse a Cypher query and materialise all CREATE / MERGE operations into a petgraph::Graph with the default NodeData / EdgeData types.
• build_graph_from_cypher_typed – generic version that accepts any types implementing CypherNode and CypherEdge.

Supported Cypher subset

Feature	Status
CREATE (n:Label {k: v})-[:TYPE]->(m)	✅ materialised + executed
MERGE (n:Label {k: v})-[:TYPE]->(m)	✅ materialised + executed
MATCH (n)-[r]->(m) WHERE n.p = v	✅ evaluated
RETURN n, n.prop AS alias / RETURN *	✅ evaluated
[DETACH] DELETE n	✅ executed
Multiple clauses in one query	✅
Semicolon-separated statements	✅

Example

use petgraph_decypher::build_graph_from_cypher;

let graph = build_graph_from_cypher(
    r#"CREATE (a:Person {name: "Alice"})-[:KNOWS]->(b:Person {name: "Bob"})"#,
)
.unwrap();

assert_eq!(graph.node_count(), 2);
assert_eq!(graph.edge_count(), 1);

Re-exports

pub use ast::BinaryOp;

pub use ast::CaseExpr;

pub use ast::Clause;

pub use ast::CypherQuery;

pub use ast::CypherValue;

pub use ast::Expression;

pub use ast::NodePattern;

pub use ast::PathPattern;

pub use ast::RelDirection;

pub use ast::RelPattern;

pub use ast::RelationshipLength;

pub use ast::ReturnItem;

pub use ast::SetItem;

pub use ast::SortDirection;

pub use ast::SortItem;

pub use ast::UnaryOp;

pub use ast::WhereExpr;

pub use error::CypherError;

pub use query::MatchStrategy;

pub use query::Parameters;

pub use query::PetgraphCypher;

pub use query::QueryResult;

pub use query::ResultValue;

pub use query::Row;

Modules

ast

Abstract Syntax Tree types for OpenCypher queries.

error

Error types for petgraph-decypher.

query

Query execution engine for running Cypher queries against a petgraph.

Structs

EdgeData

Data stored at each edge in the graph built by build_graph_from_cypher.

NodeData

Data stored at each node in the graph built by build_graph_from_cypher.

Traits

CypherEdge

Metadata required from edge weights during Cypher planning and execution.

CypherNode

Metadata required from node weights during Cypher planning and execution.

CypherProperties

Common property access used by the query planner and executor.

Functions

build_graph_from_cypher

Parse a Cypher query and build a petgraph Graph from its CREATE and MERGE clauses.

build_graph_from_cypher_typed

Parse a Cypher query and build a petgraph Graph from its CREATE and MERGE clauses using custom node and edge types.

parse_cypher

Parse a Cypher query string and return its HIR-backed query plan representation.