Basic: run one task

Use this pattern when all tasks are known at startup and finish on their own.

TaskFn::arc adapts an async closure into a shared task. TaskSpec::once permits one attempt. Supervisor::run admits the initial batch and returns after registry membership is empty and bounded cleanup finishes.

run reports the supervisor lifecycle. Its Ok(()) does not prove that every task succeeded. Use a watched task when application logic needs its final outcome; see outcomes.rs.

This task prints once and completes immediately. It does not use TaskContext. See graceful_worker.rs for a long-running task that observes cancellation.

Run with cargo run --example basic.

Complete program

use taskvisor::prelude::*;

#[tokio::main(flavor = "current_thread")]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let task: TaskRef = TaskFn::arc(|_ctx| async move {
        println!("Hello from taskvisor!");
        Ok(())
    });

    let supervisor = Supervisor::new(SupervisorConfig::default(), vec![]);
    supervisor.run(vec![TaskSpec::once("hello", task)]).await?;

    Ok(())
}