#sharing #task #job

mula

Share expensive computation with various requesters

2 releases

0.1.1 Oct 15, 2020
0.1.0 Oct 13, 2020

#1205 in Concurrency

MIT license

14KB
153 lines

mula

Mula provides a way of having several requests for a given computation be serviced without duplicating the actual computation.

Imagine you have a REST API with an endpoint that causes an expensive computation. If that endpoint receives more requests while the first one is being computed it would be nice if you could just let those new requests wait in line for the computation to end and give them all the same result.

That is what Mula allows you to do.

Example

The following example will only run the computation closure twice, once for each of the distinct inputs. The two subscriptions for "burro" will both be serviced by the same computation.

use mula::mula;

#[mula]
fn delayed_uppercase(input: &'static str) -> String {
    std::thread::sleep(std::time::Duration::from_secs(2));
    input.to_uppercase()
}

let thread1 = std::thread::spawn(move || {
    let upper = delayed_uppercase("mula");
    assert_eq!(upper, "MULA".to_string());
});

let thread2 = std::thread::spawn(move || {
    let upper = delayed_uppercase("burro");
    assert_eq!(upper, "BURRO".to_string());
});

let thread3 = std::thread::spawn(move || {
    let upper = delayed_uppercase("burro");
    assert_eq!(upper, "BURRO".to_string());
});

thread1.join();
thread2.join();
thread3.join();

License: MIT

Dependencies

~2.5MB
~50K SLoC