Crate manifold_graph 

manifold-graph

Graph storage optimizations for the Manifold embedded database.

This crate provides ergonomic, type-safe wrappers around Manifold’s core primitives for storing and querying graph edges with bidirectional indexes.

Features

• Automatic bidirectional indexes: Efficient queries for both outgoing and incoming edges
• UUID-based vertices: Fixed-width 16-byte vertex IDs with proper ordering
• Type-safe edge properties: Fixed-width tuple (bool, f32, u64, Option<u64>) for is_active, weight, and temporal tracking
• Atomic updates: Both forward and reverse indexes updated in same transaction
• Efficient traversal: Range scans leverage tuple key ordering for fast queries

Quick Start

use manifold::column_family::ColumnFamilyDatabase;
use manifold_graph::{GraphTable, GraphTableRead, Edge};
use uuid::Uuid;

let db = ColumnFamilyDatabase::open("my.db")?;
let cf = db.column_family_or_create("social")?;

let user1 = Uuid::new_v4();
let user2 = Uuid::new_v4();

// Write edges
{
    let write_txn = cf.begin_write()?;
    let mut graph = GraphTable::open(&write_txn, "edges")?;
    graph.add_edge(&user1, "follows", &user2, true, 1.0, None)?;
    drop(graph);
    write_txn.commit()?;
}

// Read with efficient traversal
let read_txn = cf.begin_read()?;
let graph = GraphTableRead::open(&read_txn, "edges")?;

// Get all outgoing edges (range scan on forward table)
for edge_result in graph.outgoing_edges(&user1)? {
    let edge = edge_result?;
    println!("{:?} -[{}]-> {:?}", edge.source, edge.edge_type, edge.target);
}

// Get all incoming edges (range scan on reverse table)
for edge_result in graph.incoming_edges(&user2)? {
    let edge = edge_result?;
    println!("{:?} -[{}]-> {:?}", edge.source, edge.edge_type, edge.target);
}

Architecture

This crate does not implement graph algorithms (BFS, DFS, PageRank, etc.). Instead, it focuses on efficient storage and provides integration traits for external graph libraries. The EdgeSource trait enables graph algorithm libraries to consume edges efficiently.

Edge Properties

Edges store fixed-width properties with temporal tracking:

• is_active: bool - For active/passive edges, soft deletes, hidden edges
• weight: f32 - General-purpose edge weight or score
• created_at: u64 - Creation timestamp in nanoseconds since Unix epoch
• deleted_at: Option<u64> - Deletion timestamp (None if not deleted)

These properties are stored as a fixed-width tuple (bool, f32, u64, Option<u64>) for efficient serialization (21 bytes total).

Re-exports

pub use edge::Edge;

pub use graph::AllEdgesIter;

pub use graph::GraphTable;

pub use graph::GraphTableRead;

pub use graph::IncomingEdgeIter;

pub use graph::OutgoingEdgeIter;

pub use integration::EdgeSource;

Modules

edge

Edge types for graph storage.

graph

Graph table implementation with bidirectional edge storage.

integration

Integration traits for external graph algorithm libraries.