Struct GraphRAGService 

pub struct GraphRAGService<G: GraphBackend> {
    recall: Arc<RecallService>,
    graph: Arc<GraphService<G>>,
    extractor: EntityExtractorService,
    config: GraphRAGConfig,
}

Service for hybrid search combining semantic search with graph expansion.

The Graph RAG service enhances traditional memory recall by:

1. Extracting entities from the user’s query
2. Expanding the knowledge graph to find related entities
3. Retrieving memories linked to those entities
4. Merging and re-ranking results from both sources

This provides contextually richer results that leverage the connections between concepts, people, and technologies in the knowledge graph.

Fields

recall: Arc<RecallService>

The recall service for semantic/text search.

graph: Arc<GraphService<G>>

The graph service for knowledge graph operations.

extractor: EntityExtractorService

The entity extractor for query analysis.

config: GraphRAGConfig

Configuration for the service.

Implementations

impl<G: GraphBackend> GraphRAGService<G>

pub const fn new( recall: Arc<RecallService>, graph: Arc<GraphService<G>>, extractor: EntityExtractorService, config: GraphRAGConfig, ) -> Self

Creates a new Graph RAG service.

Arguments

• recall - The recall service for semantic search.
• graph - The graph service for knowledge graph operations.
• extractor - The entity extractor for query analysis.
• config - Configuration for the service.

pub fn search_with_expansion( &self, query: &str, filter: &SearchFilter, limit: usize, expansion: Option<ExpansionConfig>, ) -> Result<GraphSearchResults>

Performs a hybrid search with graph expansion.

This method:

1. Runs traditional semantic/text search via RecallService
2. Extracts entities from the query
3. Traverses the knowledge graph to find related entities
4. Retrieves memories linked to those entities
5. Merges and re-ranks all results

Arguments

• query - The search query.
• filter - Search filter to apply.
• limit - Maximum number of results to return.
• expansion - Optional expansion configuration.

Returns

A GraphSearchResults containing all matched memories with provenance.

Errors

Returns an error if search or graph operations fail.

fn expand_from_entities( &self, entity_names: &[String], expansion: &ExpansionConfig, ) -> Result<HashMap<MemoryId, (f32, EntityId, usize)>>

Expands the graph from extracted entity names.

fn expand_single_entity( &self, entity: &Entity, depth: usize, expansion: &ExpansionConfig, results: &mut HashMap<MemoryId, (f32, EntityId, usize)>, ) -> Result<()>

Expands a single entity and collects memory links.

fn score_and_insert_memories( &self, memory_ids: &[MemoryId], source_entity: &EntityId, hop_count: usize, use_weight: bool, results: &mut HashMap<MemoryId, (f32, EntityId, usize)>, )

Calculates scores and inserts memory links into results.

fn update_or_insert_memory( results: &mut HashMap<MemoryId, (f32, EntityId, usize)>, memory_id: &MemoryId, score: f32, source_entity: &EntityId, hop_count: usize, )

Updates an existing memory entry or inserts a new one.

fn find_entities_by_name(&self, name: &str) -> Result<Vec<Entity>>

Finds entities by name (case-insensitive search).

fn traverse_entity( &self, entity_id: &EntityId, max_depth: usize, ) -> Result<Vec<(EntityId, usize)>>

Traverses the graph from an entity up to the specified depth.

fn add_neighbors_to_frontier( &self, entity_id: &EntityId, current_depth: usize, frontier: &mut Vec<(EntityId, usize)>, ) -> Result<()>

Adds neighbors of an entity to the traversal frontier.

fn get_entity_memory_links(&self, entity_id: &EntityId) -> Result<Vec<MemoryId>>

Gets memory IDs linked to an entity via mentions.

fn merge_results( &self, semantic: SearchResult, graph: HashMap<MemoryId, (f32, EntityId, usize)>, _expansion: &ExpansionConfig, ) -> Result<Vec<GraphSearchHit>>

Merges semantic results with graph expansion results.

fn merge_single_graph_result( &self, hits: &mut HashMap<String, GraphSearchHit>, id: String, memory_id: &MemoryId, graph_score: f32, source_entity: EntityId, hop_count: usize, )

Merges a single graph result into the hits map.

pub fn search_semantic_only( &self, query: &str, filter: &SearchFilter, limit: usize, ) -> Result<GraphSearchResults>

Performs semantic-only search (no graph expansion).

This is useful for comparison or when graph expansion is not desired.

Errors

Returns an error if the semantic search operation fails.

pub fn search_graph_only( &self, query: &str, limit: usize, expansion: Option<ExpansionConfig>, ) -> Result<GraphSearchResults>

Performs graph-only search (no semantic search).

Searches by extracting entities from the query and expanding the graph.

Errors

Returns an error if entity extraction or graph expansion fails.