# Graph Query and Search API

## Module
Graph

## Status
IMPLEMENTED

## Description
Graph API with query, search, and path services for traversing and querying dependency graphs.

## Implementation Details
- **Query service**: `src/Graph/StellaOps.Graph.Api/Services/IGraphQueryService.cs`, `InMemoryGraphQueryService.cs` -- graph node/edge query with filtering
- **Search service**: `src/Graph/StellaOps.Graph.Api/Services/IGraphSearchService.cs`, `InMemoryGraphSearchService.cs` -- full-text search across graph entities
- **Path service**: `src/Graph/StellaOps.Graph.Api/Services/IGraphPathService.cs`, `InMemoryGraphPathService.cs` -- shortest-path and reachability path queries
- **Repository**: `src/Graph/StellaOps.Graph.Api/Services/InMemoryGraphRepository.cs` -- in-memory graph data store
- **Search contracts**: `src/Graph/StellaOps.Graph.Api/Contracts/SearchContracts.cs` -- search request/response DTOs
- **Lineage contracts**: `src/Graph/StellaOps.Graph.Api/Contracts/LineageContracts.cs` -- lineage query contracts
- **Reachability contracts**: `src/Graph/StellaOps.Graph.Api/Contracts/ReachabilityContracts.cs` -- reachability query contracts
- **Rate limiting**: `src/Graph/StellaOps.Graph.Api/Services/RateLimiterService.cs` -- query rate limiting
- **Tests**: `src/Graph/__Tests/StellaOps.Graph.Api.Tests/QueryServiceTests.cs`, `SearchServiceTests.cs`, `PathServiceTests.cs`, `RateLimiterServiceTests.cs`
- **Source**: Feature matrix scan

## E2E Test Plan
- [ ] Verify query API returns nodes and edges matching filter criteria
- [ ] Test full-text search returns ranked results across graph entities
- [ ] Verify path queries find shortest paths between nodes
- [ ] Test rate limiting prevents query abuse
- [ ] Verify search contracts handle empty results and pagination