grpc_graphql_gateway

High-performance Rust gateway bridging gRPC to GraphQL with Apollo Federation v2.

Transform gRPC microservices into a unified GraphQL API. Zero GraphQL code required.

🚀 Performance at a Glance

Performance Rankings (Rust):
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
1. grpc_graphql_gateway    ████████████████████ 112,000 req/s 🚀
2. async-graphql (Actix)   █████████░░░░░░░░░░░  45,000 req/s
3. Juniper (Actix)         ████████░░░░░░░░░░░░  39,000 req/s

Data Efficiency Mode (GBP Ultra):
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
JSON Payload (100MB)       ████████████████████ 100%
GBP Ultra (800KB)          ▏                    0.8% ⚡ (<1ms latency)

✨ Features

Category	Capabilities
Core	Schema generation, Queries/Mutations/Subscriptions, WebSocket, File uploads
Federation	Apollo Federation v2, Entity resolution, DataLoader batching, No N+1
Production	Health checks, Prometheus, OpenTelemetry, Rate limiting, Circuit breaker
Security	Query depth/complexity limits, Introspection control, Query whitelisting
Performance	SIMD JSON, Sharded Cache, Response caching (Redis), APQ, Request collapsing
Connectors	REST APIs, OpenAPI integration, Multi-descriptor stitching

📦 Quick Start

[dependencies]
grpc_graphql_gateway = "0.5.5"
tokio = { version = "1", features = ["full"] }

use grpc_graphql_gateway::{Gateway, GrpcClient};

const DESCRIPTORS: &[u8] = include_bytes!(concat!(env!("OUT_DIR"), "/descriptor.bin"));

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    Gateway::builder()
        .with_descriptor_set_bytes(DESCRIPTORS)
        .add_grpc_client("service", GrpcClient::builder("http://localhost:50051").connect_lazy()?)
        .build()?
        .serve("0.0.0.0:8888")
        .await
}

Endpoints: http://localhost:8888/graphql | ws://localhost:8888/graphql/ws

🌐 Federation

Gateway::builder()
    .enable_federation()
    .with_entity_resolver(Arc::new(resolver))
    .build()?;

🔧 Production Config

Gateway::builder()
    .enable_health_checks()           // /health, /ready
    .enable_metrics()                 // /metrics (Prometheus)
    .enable_tracing()                 // OpenTelemetry
    .with_query_depth_limit(10)       // DoS protection
    .with_query_complexity_limit(100)
    .with_response_cache(CacheConfig::default())
    .with_circuit_breaker(CircuitBreakerConfig::default())
    .build()?;

📚 Examples

cargo run --example greeter      # Basic queries/mutations/subscriptions
cargo run --example federation   # 3 federated subgraphs

🔗 Links

📖 Full Documentation • 📦 Crates.io • 💻 GitHub

---

Made with ❤️ by Protocol Lattice