tower-rate-limiter

Crates.io · Documentation

Keyed, fixed-window HTTP rate limiting middleware for Tower. Limit repeated requests by account, API client, peer address, or any other application-defined identity.

• Tower-first core with optional Axum integration
• Fixed or request-derived quotas
• Process-local memory and shared Redis Stores
• Custom keys, responses, bypass rules, and Store failure behavior
• Optional structured tracing for Store failures
• IETF RateLimit and RateLimit-Policy response fields

Guide · API documentation · Examples

Quick start

The default feature includes the process-local MemoryStore. The crate requires Rust 1.96 or newer.

[dependencies]
tower-rate-limiter = "0.1"

use std::time::Duration;
use tower::Layer;
use tower_rate_limiter::{IpKeyExtractor, MemoryStore, RateLimitLayer};

let limiter = RateLimitLayer::builder(IpKeyExtractor::new())
    .policy_name("public-api")
    .limit(100)
    .window(Duration::from_secs(60))
    .with_store(MemoryStore::new())
    .build()
    .expect("valid rate-limit policy");

let service = limiter.layer(inner_service);

The Store is always explicit through .with_store(...). IpKeyExtractor reads only the peer SocketAddr from request extensions; Axum applications must provide ConnectInfo. Behind a trusted proxy, ClientIpKeyExtractor can check supported client-IP headers first and fall back to that peer. Only use its header-derived identity when the proxy removes or overwrites every accepted header. See the quick-start guide for a complete runnable example.

Stores

For Redis with Tokio and the default transaction implementation:

[dependencies]
tower-rate-limiter = {
    version = "0.1",
    default-features = false,
    features = ["redis", "runtime-tokio"],
}

Use redis-lua instead of redis for the Lua implementation, or runtime-smol instead of runtime-tokio for Smol. The application provides an established Redis connection and owns its lifecycle.

Documentation

Runnable Tower, Axum, dynamic-quota, proxy, and Redis integrations are collected in examples/.

Contributing

Bug reports, feature requests, and contributions are welcome through GitHub Issues.

License

Licensed under either

• Apache License, Version 2.0 (LICENSE-APACHE); or
• MIT License (LICENSE-MIT).