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pub mod error;
pub mod future;
use self::{error::Error, future::ResponseFuture};
use std::task::{Context, Poll};
use tower_service::Service;
#[derive(Debug)]
pub struct Optional<T> {
inner: Option<T>,
}
impl<T> Optional<T> {
pub fn new<Request>(inner: Option<T>) -> Optional<T>
where
T: Service<Request>,
T::Error: Into<Error>,
{
Optional { inner }
}
}
impl<T, Request> Service<Request> for Optional<T>
where
T: Service<Request>,
T::Error: Into<Error>,
{
type Response = T::Response;
type Error = Error;
type Future = ResponseFuture<T::Future>;
fn poll_ready(&mut self, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
match self.inner {
Some(ref mut inner) => match inner.poll_ready(cx) {
Poll::Ready(r) => Poll::Ready(r.map_err(Into::into)),
Poll::Pending => Poll::Pending,
},
None => Poll::Ready(Ok(())),
}
}
fn call(&mut self, request: Request) -> Self::Future {
let inner = self.inner.as_mut().map(|i| i.call(request));
ResponseFuture::new(inner)
}
}