Existing Implementations
The Graph API ecosystem includes two ready-to-use graph implementations that cater to different use cases and performance requirements. This section provides an overview of the existing implementations, their features, and suitability for different applications.
Core Implementations
The Graph API project provides two main graph implementations:
-
SimpleGraph: A reference implementation built specifically for the Graph API. It fully supports all Graph API features, including most index types, making it ideal for testing Graph API functionality and serving as a blueprint for new implementations.
-
PetGraph: An adapter for the excellent and widely-used petgraph crate. This demonstrates Graph API compatibility with established Rust graph libraries and is a great choice for performance-sensitive applications or projects already using petgraph.
Choosing an Implementation
When deciding which graph implementation to use, consider the following factors:
Feature Support
Different implementations support different features:
| Feature | SimpleGraph | PetGraph |
|---|---|---|
| Vertex label indexes | ✅ | ❌ |
| Edge label indexes | ✅ | ❌ |
| Vertex hash indexes | ✅ | ❌ |
| Edge hash indexes | ❌ | ❌ |
| Vertex range indexes | ✅ | ❌ |
| Edge range indexes | ❌ | ❌ |
| Vertex full-text indexes | ✅ | ❌ |
| Edge adjacent label indexes* | ✅ | ❌ |
| Graph clearing | ✅ | ✅ |
* Edge adjacent indexes are not fully supported in graph-api yet.
Performance Characteristics
Performance varies between implementations:
- SimpleGraph: Primarily designed for feature completeness and testing; not optimized for high performance.
- PetGraph: A mature, well-optimized, and widely-used graph library suitable for production use.
Memory Usage
- SimpleGraph: Memory usage is straightforward but not heavily optimized.
- PetGraph: Leverages petgraph's memory model, which is generally efficient.
Integration
- SimpleGraph: Best for demonstrating and testing Graph API features or as a starting point for custom implementations.
- PetGraph: Ideal for integrating Graph API capabilities into projects already using petgraph or when requiring petgraph's performance characteristics.
Creating Your Own Implementation
If the existing implementations don't meet your needs, you can create your own by implementing the Graph trait. See
the Implementation Guide for detailed instructions on creating a custom graph
implementation.
Future Implementations
The Graph API is designed to support a variety of graph implementations.
Community contributions of new graph implementations are welcomed and encouraged!