Crate tokio_tasks

Task manager for tokio. Facilitates clean shutdow of applications, and async cancelation of tasks

Example

use tokio_tasks::{TaskBuilder, run_tasks, shutdown, cancelable, RunToken};

// Main task, program will shut down if when finishes
async fn main_task(run_token: RunToken) -> Result<(), String> {
    println!("Main task start");
    match cancelable(&run_token, tokio::time::sleep(std::time::Duration::from_secs(10))).await {
       Ok(()) => println!("Main task finished"),
       Err(_) => println!("Main task cancled"),
    }
    Ok(())
}

// Critical task, program will shut down if this finished with an error
async fn critical_task(run_token: RunToken) -> Result<(), String> {
    println!("Critical task start");
    match cancelable(&run_token, tokio::time::sleep(std::time::Duration::from_secs(1))).await {
       Ok(()) => println!("Critical task finished"),
       Err(_) => println!("Critical task cancled"),
    }
    Ok(())
}

TaskBuilder::new("main_task")
    .main()
    .shutdown_order(1)
    .create(|rt| main_task(rt));

TaskBuilder::new("critical_task")
    .critical()
    .shutdown_order(2)
    .create(|rt| critical_task(rt));

// Normally one would register the program to stop on ctrl+c
// tokio::spawn(async {
//    tokio::signal::ctrl_c().await.unwrap();
//    shutdown("ctrl+c".to_string());
// });

// We just shut down after a little while
tokio::spawn(async {
   tokio::time::sleep(std::time::Duration::from_millis(20)).await;
   shutdown("timeout".to_string());
});
run_tasks().await;

Re-exports

• pub use task::FinishState;

Structs

• CancelledError
  Error returned by cancelable when c was canceled before the future returned
• RunToken
  Similar to a [tokio_util::sync::CancellationToken], the RunToken encapsulates the possibility of canceling an async command. However it also allows pausing and resuming the async command, and it is possible to wait in both a blocking fashion and an asynchronous fashion.
• Task
  A possible running task, with a return value of Result<T, E>
• TaskBuilder
  Builder to create a new task
• WaitForCancellationFuture
  Wait until task cancellation is completed

Enums

• WaitError
  Error return while waiting for a task

Traits

• TaskBase
  Base trait for all tasks, that is independent of the return type

Functions

• cancelable
  Return result from fut, unless run_token is canceled before fut is done
• list_tasks
  Return a list of all currently running tasks
• run_tasks
  Wait until all tasks are done or shutdown has been called
• shutdown
  Cancel all tasks in shutdown order
• try_list_tasks_for
  Try to return a list of all currently running tasks, if we cannot acquire the lock for the tasks before duration has passed return None

Type Aliases

• BoxFuture