DelayHandler

An abstration over DelayQueue that allows you to create a delay, with associated data.

Users can add data to the delay-map with insert(). The associated data is removed and returned when delay is timedout by .awaiting on next(). Users can also prematurely remove the delay from the delay-map with remove().

Examples

1. Insert 3 numbers into delay-map with 10s delays, print them as they timeout

let mut handler = DelayHandler::default();
// Adds 1, 2, 3 to the delay-map, each with 10s delay
handler.insert(1, Duration::from_secs(10));
handler.insert(2, Duration::from_secs(10));
handler.insert(3, Duration::from_secs(10));

// Expect a delay of ~10s, after which 1, 2, 3 should print to stdout, in quick succession.
while let Some(expired) = handler.next().await {
    println!("{}", expired);
}

2. Insert 3 numbers into delay-map with different delays, print them as they timeout

let mut handler = DelayHandler::default();
// Adds 1, 2 to the delay-map, with different delays
handler.insert(1, Duration::from_secs(10));
handler.insert(2, Duration::from_secs(5));

// With a delay of ~5s between, the prints should come in the order of 2 and 1.
while let Some(expired) = handler.next().await {
    println!("{}", expired);
}

3. Insert 3 numbers into delay-map with different delays, remove print as delays are timedout

let mut handler = DelayHandler::default();
// Adds 1, 2, 3 to the delay-map, each with different delays
handler.insert(1, Duration::from_secs(15));
handler.insert(2, Duration::from_secs(5));
handler.insert(3, Duration::from_secs(10));

// Remove 3 from the delay-map
handler.remove(&3);

// Prints should be in the order of first 2 and ~10s later 1.
while let Some(expired) = handler.next().await {
    println!("{}", expired);
}