Crate axum_limit

axum-limit

This crate provides an efficient rate limiting mechanism using token buckets, specifically designed for asynchronous web applications with a strong focus on extractor-based rate limits.

Features

• Configurable rate limits using extractors, allowing for flexible limit strategies per route.
• Supports various time granularities for rate limits (per second, per minute, per hour, and per day).
• Easily integrates with Axum, using extractors to apply rate limits seamlessly within your application routes.
• Utilizes DashMap for concurrent state management across asynchronous tasks.

Example

Here is a basic example showing how to use the crate with Axum routes:

use http::Uri;
use axum_limit::{Limit, LimitState, LimitPerSecond};
use axum::{Router, routing::get, response::IntoResponse};

async fn route_handler(_: LimitPerSecond<5, Uri>) -> impl IntoResponse {
    // Handler logic here, automatically enforcing the rate limit
}

fn main() {
    let _app: Router<()> = Router::new()
        .route("/your_route", get(route_handler))
        .with_state(LimitState::<Uri>::default());
}

This example demonstrates setting up a rate limit of 5 requests per second on a specific route. The Limit extractor automatically enforces these limits based on the incoming requests.

For more comprehensive examples, please check the examples directory in this repository.

Structs

Limit

Represents a rate limit configuration with generic parameters for count and time period. This struct uses generics to allow flexible integration with any extractor that implements the Key trait.

LimitState

Manages the state of rate limits for various keys. This struct holds a concurrent map of keys to their corresponding TokenBucket instances, enabling efficient state management across asynchronous tasks.

Enums

LimitRejection

Enumerates possible failure modes for rate limiting when extracting from request parts.

Traits

Key

Trait defining the requirements for a key extractor, which is used to uniquely identify limit subjects and extract rate limit parameters dynamically in request processing.

Type Aliases

LimitPerDay

Rate limit configured to apply per day.

LimitPerHour

Rate limit configured to apply per hour.

LimitPerMinute

Rate limit configured to apply per minute.

LimitPerSecond

Rate limit configured to apply per second.