How to Cancel Async Tasks in Rust

Cancel an async task in Rust by dropping its JoinHandle returned from tokio::task::spawn. When the handle is dropped, the task is immediately aborted and its resources are cleaned up.

use tokio::task::spawn;

#[tokio::main]
async fn main() {
    let handle = spawn(async {
        loop {
            tokio::time::sleep(tokio::time::Duration::from_secs(1)).await;
            println!("Still running");
        }
    });

    // Cancel the task by dropping the handle
    drop(handle);
}

Think of a spawned task as a background worker. The JoinHandle is your remote control for that worker. If you throw away the remote control (drop the handle), the worker stops immediately and cleans up after itself. This is the standard way to stop a task you no longer need.