warp/filter/
recover.rs

1use std::future::Future;
2use std::pin::Pin;
3use std::task::{Context, Poll};
4
5use futures_util::{ready, TryFuture};
6use pin_project::pin_project;
7
8use super::{Filter, FilterBase, Func, Internal};
9use crate::generic::Either;
10use crate::reject::IsReject;
11use crate::route;
12
13#[derive(Clone, Copy, Debug)]
14pub struct Recover<T, F> {
15    pub(super) filter: T,
16    pub(super) callback: F,
17}
18
19impl<T, F> FilterBase for Recover<T, F>
20where
21    T: Filter,
22    F: Func<T::Error> + Clone + Send,
23    F::Output: TryFuture + Send,
24    <F::Output as TryFuture>::Error: IsReject,
25{
26    type Extract = (Either<T::Extract, (<F::Output as TryFuture>::Ok,)>,);
27    type Error = <F::Output as TryFuture>::Error;
28    type Future = RecoverFuture<T, F>;
29    #[inline]
30    fn filter(&self, _: Internal) -> Self::Future {
31        let idx = route::with(|route| route.matched_path_index());
32        RecoverFuture {
33            state: State::First(self.filter.filter(Internal), self.callback.clone()),
34            original_path_index: PathIndex(idx),
35        }
36    }
37}
38
39#[allow(missing_debug_implementations)]
40#[pin_project]
41pub struct RecoverFuture<T: Filter, F>
42where
43    T: Filter,
44    F: Func<T::Error>,
45    F::Output: TryFuture + Send,
46    <F::Output as TryFuture>::Error: IsReject,
47{
48    #[pin]
49    state: State<T, F>,
50    original_path_index: PathIndex,
51}
52
53#[pin_project(project = StateProj)]
54enum State<T, F>
55where
56    T: Filter,
57    F: Func<T::Error>,
58    F::Output: TryFuture + Send,
59    <F::Output as TryFuture>::Error: IsReject,
60{
61    First(#[pin] T::Future, F),
62    Second(#[pin] F::Output),
63    Done,
64}
65
66#[derive(Copy, Clone)]
67struct PathIndex(usize);
68
69impl PathIndex {
70    fn reset_path(&self) {
71        route::with(|route| route.reset_matched_path_index(self.0));
72    }
73}
74
75impl<T, F> Future for RecoverFuture<T, F>
76where
77    T: Filter,
78    F: Func<T::Error>,
79    F::Output: TryFuture + Send,
80    <F::Output as TryFuture>::Error: IsReject,
81{
82    type Output = Result<
83        (Either<T::Extract, (<F::Output as TryFuture>::Ok,)>,),
84        <F::Output as TryFuture>::Error,
85    >;
86
87    fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
88        loop {
89            let pin = self.as_mut().project();
90            let (err, second) = match pin.state.project() {
91                StateProj::First(first, second) => match ready!(first.try_poll(cx)) {
92                    Ok(ex) => return Poll::Ready(Ok((Either::A(ex),))),
93                    Err(err) => (err, second),
94                },
95                StateProj::Second(second) => {
96                    let ex2 = match ready!(second.try_poll(cx)) {
97                        Ok(ex2) => Ok((Either::B((ex2,)),)),
98                        Err(e) => Err(e),
99                    };
100                    self.set(RecoverFuture {
101                        state: State::Done,
102                        ..*self
103                    });
104                    return Poll::Ready(ex2);
105                }
106                StateProj::Done => panic!("polled after complete"),
107            };
108
109            pin.original_path_index.reset_path();
110            let fut2 = second.call(err);
111            self.set(RecoverFuture {
112                state: State::Second(fut2),
113                ..*self
114            });
115        }
116    }
117}
warp/filter/recover.rs

warp/filter/
recover.rs
