How to Implement Cooperative Cancellation in Async Rust

Use tokio::select! to run multiple async tasks concurrently and cancel the remaining ones when any task completes or a timeout occurs.

use tokio::time::{timeout, Duration};

async fn cooperative_cancel() {
    let task1 = async { /* long running work */ };
    let task2 = async { /* another task */ };

    tokio::select! {
        _ = task1 => println!("Task 1 finished"),
        _ = task2 => println!("Task 2 finished"),
        _ = tokio::time::sleep(Duration::from_secs(5)) => println!("Timeout"),
    }
}

Cooperative cancellation lets you stop a running background task immediately when another event happens, like a user clicking cancel or a timer expiring. It works like a group of runners where the race ends for everyone as soon as one person crosses the finish line. This prevents your application from wasting resources on tasks that are no longer needed.