Motore

Motore is an async middleware abstraction powered by AFIT and RPITIT.

Around Motore, we build modular and reusable components for building robust networking clients and servers.

Motore is greatly inspired by Tower.

Overview

Motore uses AFIT and RPITIT to reduce the mental burden of writing asynchronous code, especially to avoid the overhead of Box to make people less anxious.

The core abstraciton of Motore is the Service trait:

pub trait Service<Cx, Request> {
    /// Responses given by the service.
    type Response;
    /// Errors produced by the service.
    type Error;

    /// Process the request and return the response asynchronously.
    async fn call<'s, 'cx>(&'s mut self, cx: &'cx mut Cx, req: Request) -> Result<Self::Response, Self::Error>;
}

Getting Started

Using AFIT, we can write asynchronous code in a very concise and readable way.

pub struct Timeout<S> {
    inner: S,
    duration: Duration,
}
impl<Cx, Req, S> Service<Cx, Req> for Timeout<S>
where
    Req: 'static + Send,
    S: Service<Cx, Req> + 'static + Send,
    Cx: 'static + Send,
    S::Error: Send + Sync + Into<BoxError>,
{
    type Response = S::Response;
    type Error = BoxError;

    async fn call<'s, 'cx>(&'s mut self, cx: &'cx mut Cx, req: Req) -> Result<Self::Response, Self::Error> {
        let sleep = tokio::time::sleep(self.duration);
        tokio::select! {
            r = self.inner.call(cx, req) => {
                r.map_err(Into::into)
            },
            _ = sleep => Err(std::io::Error::new(std::io::ErrorKind::TimedOut, "service time out").into()),
        }
    }
}

We also provided the #[motore::service] macro to make writing a Service more async-native:

use motore::service;
pub struct S<I> {
    inner: I,
}
#[service]
impl<Cx, Req, I> Service<Cx, Req> for S<I>
where
   Req: Send + 'static,
   I: Service<Cx, Req> + Send + 'static,
   Cx: Send + 'static,
{
    async fn call(&mut self, cx: &mut Cx, req: Req) -> Result<I::Response, I::Error> {
        self.inner.call(cx, req).await
    }
}

Last modified March 12, 2024 : doc: sync User guide to Kitex multi-service (#1024) (1da567f)