async-rate-limiter

async-rate-limiter implements a token bucket algorithm that can be used to limit API access frequency.

Example

Update your Cargo.toml:

[dependencies]
# Change features to ["rt-async-std"] if you are using async-std runtime.
async-rate-limiter = { version = "1.39.2", features = ["rt-tokio"] }

Thanks to Rust’s async functionality, this crate is very simple to use. Just put your function call after RateLimiter::acquire().await, then the function will be called with the specified rate limit.

Here is a simple example:

use async_rate_limiter::RateLimiter;
use std::time::Duration;

#[tokio::main]
async fn main() {
    let mut rl = RateLimiter::new(3, 5);
    
    let ok = rl.acquire(None).await;
    assert!(ok);
    println!("Do something that you want to limit the rate ...");

    // acquire with a timeout
    let ok = rl.acquire(Some(Duration::from_secs(10))).await;
    if ok {
        println!("Do something that you want to limit the rate ...");
    }
}

async-rate-limiter can support different async runtimes, tokio & async-std are supported currently. You can use features to switch async runtimes.