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#![doc(html_root_url = "https://docs.rs/tower-load-shed/0.1.0")]
#![cfg_attr(test, deny(warnings))]
#![deny(missing_debug_implementations, missing_docs, rust_2018_idioms)]
#![allow(elided_lifetimes_in_paths)]
use futures::Poll;
use tower_service::Service;
pub mod error;
pub mod future;
mod layer;
use crate::error::Error;
use crate::future::ResponseFuture;
pub use crate::layer::LoadShedLayer;
#[derive(Debug)]
pub struct LoadShed<S> {
inner: S,
is_ready: bool,
}
impl<S> LoadShed<S> {
pub fn new(inner: S) -> Self {
LoadShed {
inner,
is_ready: false,
}
}
}
impl<S, Req> Service<Req> for LoadShed<S>
where
S: Service<Req>,
S::Error: Into<Error>,
{
type Response = S::Response;
type Error = Error;
type Future = ResponseFuture<S::Future>;
fn poll_ready(&mut self) -> Poll<(), Self::Error> {
self.is_ready = self.inner.poll_ready().map_err(Into::into)?.is_ready();
Ok(().into())
}
fn call(&mut self, req: Req) -> Self::Future {
if self.is_ready {
self.is_ready = false;
ResponseFuture::called(self.inner.call(req))
} else {
ResponseFuture::overloaded()
}
}
}
impl<S: Clone> Clone for LoadShed<S> {
fn clone(&self) -> Self {
LoadShed {
inner: self.inner.clone(),
is_ready: false,
}
}
}