5 releases (3 stable)
1.1.0 | Feb 17, 2019 |
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1.0.1 | Feb 17, 2019 |
0.2.0-dev | Feb 17, 2019 |
0.1.0-dev | Feb 17, 2019 |
#1245 in Asynchronous
11KB
191 lines
tokio-lock
Access an object from a single Tokio task.
Why?
Tokio futures run in a multi-threaded environment, which makes accessing an object from different futures complicated. In many cases, however, the object is not thread safe, and has to be accessed from a single thread.
As an example, imagine writing HTTP wrapper for an RPC server. Most likely, this has to be done either with a MPSC (multiple producer single consumer) queue and a large enum of possible messages, or with a mutex guarding access to the object.
This library creates a convenient abstraction on top of MPSC, that is managed internally.
Quick example
extern crate futures;
extern crate tokio;
extern crate tokio_lock;
use futures::prelude::*;
use futures::future::{self, FutureResult};
use tokio_lock::{Lock, Error};
// Create a Lock instance
let mut lock = Lock::new();
struct TestObject {
field: u32,
}
// Create a future that is going to manage the `TestObject` instance.
// NOTE: Object is consumed in the process.
let manage = lock.manage(TestObject { field: 42 });
// Borrow an object from `lock` and execute given closure.
let get_field = lock.get(|obj| -> FutureResult<u32, Error> {
future::ok(obj.field)
}).map(move |field| {
assert_eq!(field, 42);
// Stop managing the object
// NOTE: This may not be needed in the most of the cases.
lock.stop();
});
// NOTE: `manage` is a future and has to be run
tokio::run(manage.join(get_field).map_err(|err| {
panic!("Got error");
}).map(|_| ()));
Using tokio-lock
Please check our documentation for details.
Dependencies
~3MB
~45K SLoC