Struct NovaGraphDb 

pub struct NovaGraphDb { /* private fields */ }

High-level graph database wrapper used by application handlers.

NovaGraphDb composes a backend GraphStore implementation and exposes a small, ergonomic API for executing queries, upserting nodes/edges, and traversing subgraphs. The struct is Clone and intended to be injected into request extensions by the plugin.

Implementations

impl NovaGraphDb

pub fn new(store: Arc<dyn GraphStore>) -> Self

Construct a new wrapper around the provided store adapter.

pub fn in_memory() -> Self

Create an in-memory instance useful for testing and examples.

Examples found in repository

examples/simple.rs (line 7)

async fn main() {
    // Construct an in-memory graph store and upsert a couple of nodes/edges.
    let graph = NovaGraphDb::in_memory();

    let mut props = HashMap::new();
    props.insert("name".to_string(), serde_json::json!("Alice"));
    let node = GraphNode {
        id: "n1".to_string(),
        labels: vec!["Person".to_string()],
        properties: props,
    };

    graph.upsert_node(node).await.unwrap();

    let mut props2 = HashMap::new();
    props2.insert("name".to_string(), serde_json::json!("Bob"));
    let node2 = GraphNode {
        id: "n2".to_string(),
        labels: vec!["Person".to_string()],
        properties: props2,
    };

    graph.upsert_node(node2).await.unwrap();

    let edge = GraphEdge {
        id: "e1".to_string(),
        from: "n1".to_string(),
        to: "n2".to_string(),
        rel_type: "FRIEND".to_string(),
        properties: HashMap::new(),
    };

    graph.upsert_edge(edge).await.unwrap();

    let sub = graph.traverse_json("n1", 2).await.unwrap();
    println!("subgraph: {}", sub);
}

pub fn neo4j( uri: impl Into<String>, user: impl Into<String>, password: impl Into<String>, ) -> Self

Create a Neo4j-backed wrapper (adapter lives in neo4j.rs).

pub fn surreal( endpoint: impl Into<String>, namespace: impl Into<String>, database: impl Into<String>, ) -> Self

Create a SurrealDB-backed wrapper.

pub fn surreal_with_auth( endpoint: impl Into<String>, namespace: impl Into<String>, database: impl Into<String>, username: impl Into<String>, password: impl Into<String>, ) -> Self

Create a SurrealDB-backed wrapper with basic auth credentials.

pub async fn execute( &self, query: GraphQuery, ) -> Result<JsonValue, GraphDbError>

Execute a GraphQuery against the backend.

pub async fn upsert_node(&self, node: GraphNode) -> Result<(), GraphDbError>

Upsert a node.

Examples found in repository

examples/simple.rs (line 17)

async fn main() {
    // Construct an in-memory graph store and upsert a couple of nodes/edges.
    let graph = NovaGraphDb::in_memory();

    let mut props = HashMap::new();
    props.insert("name".to_string(), serde_json::json!("Alice"));
    let node = GraphNode {
        id: "n1".to_string(),
        labels: vec!["Person".to_string()],
        properties: props,
    };

    graph.upsert_node(node).await.unwrap();

    let mut props2 = HashMap::new();
    props2.insert("name".to_string(), serde_json::json!("Bob"));
    let node2 = GraphNode {
        id: "n2".to_string(),
        labels: vec!["Person".to_string()],
        properties: props2,
    };

    graph.upsert_node(node2).await.unwrap();

    let edge = GraphEdge {
        id: "e1".to_string(),
        from: "n1".to_string(),
        to: "n2".to_string(),
        rel_type: "FRIEND".to_string(),
        properties: HashMap::new(),
    };

    graph.upsert_edge(edge).await.unwrap();

    let sub = graph.traverse_json("n1", 2).await.unwrap();
    println!("subgraph: {}", sub);
}

pub async fn upsert_edge(&self, edge: GraphEdge) -> Result<(), GraphDbError>

Upsert an edge.

Examples found in repository

examples/simple.rs (line 37)

async fn main() {
    // Construct an in-memory graph store and upsert a couple of nodes/edges.
    let graph = NovaGraphDb::in_memory();

    let mut props = HashMap::new();
    props.insert("name".to_string(), serde_json::json!("Alice"));
    let node = GraphNode {
        id: "n1".to_string(),
        labels: vec!["Person".to_string()],
        properties: props,
    };

    graph.upsert_node(node).await.unwrap();

    let mut props2 = HashMap::new();
    props2.insert("name".to_string(), serde_json::json!("Bob"));
    let node2 = GraphNode {
        id: "n2".to_string(),
        labels: vec!["Person".to_string()],
        properties: props2,
    };

    graph.upsert_node(node2).await.unwrap();

    let edge = GraphEdge {
        id: "e1".to_string(),
        from: "n1".to_string(),
        to: "n2".to_string(),
        rel_type: "FRIEND".to_string(),
        properties: HashMap::new(),
    };

    graph.upsert_edge(edge).await.unwrap();

    let sub = graph.traverse_json("n1", 2).await.unwrap();
    println!("subgraph: {}", sub);
}

pub async fn traverse_json( &self, start: &str, max_depth: usize, ) -> Result<JsonValue, GraphDbError>

Traverse the graph and return JSON representing the subgraph.

Examples found in repository

examples/simple.rs (line 39)

async fn main() {
    // Construct an in-memory graph store and upsert a couple of nodes/edges.
    let graph = NovaGraphDb::in_memory();

    let mut props = HashMap::new();
    props.insert("name".to_string(), serde_json::json!("Alice"));
    let node = GraphNode {
        id: "n1".to_string(),
        labels: vec!["Person".to_string()],
        properties: props,
    };

    graph.upsert_node(node).await.unwrap();

    let mut props2 = HashMap::new();
    props2.insert("name".to_string(), serde_json::json!("Bob"));
    let node2 = GraphNode {
        id: "n2".to_string(),
        labels: vec!["Person".to_string()],
        properties: props2,
    };

    graph.upsert_node(node2).await.unwrap();

    let edge = GraphEdge {
        id: "e1".to_string(),
        from: "n1".to_string(),
        to: "n2".to_string(),
        rel_type: "FRIEND".to_string(),
        properties: HashMap::new(),
    };

    graph.upsert_edge(edge).await.unwrap();

    let sub = graph.traverse_json("n1", 2).await.unwrap();
    println!("subgraph: {}", sub);
}

Trait Implementations

impl Clone for NovaGraphDb

fn clone(&self) -> NovaGraphDb

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl NovaPlugin for NovaGraphDb

Plugin wiring for graph database support.

NovaGraphDb implements NovaPlugin so it can be registered with NovaApp. The plugin injects a cloned NovaGraphDb into request extensions to enable the NovaGraph extractor in handlers.

fn name(&self) -> &'static str

Human-readable plugin name used in logs.

fn on_init<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = ()> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Initialization hook called during application startup.

fn extend_router(&self, router: Router<()>) -> Router<()>

Extend the provided Router<()> with plugin routes or layers.

fn on_shutdown<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = ()> + Send + 'async_trait>>

where 'life0: 'async_trait, Self: 'async_trait,

Shutdown hook called during application shutdown. Default is noop.