tihu/
middleware.rs

1use super::handler::Handler;
2use std::marker::PhantomData;
3
4pub trait Middleware<In, E: Handler<In>> {
5    type Output: Handler<In>;
6    fn transform(self, handler: E) -> Self::Output;
7    fn chain<Out, M2, E3>(self, other: M2) -> JoinMiddleware<In, Out, Self::Output, Self, E, M2, E3>
8    where
9        Self: Sized + 'static,
10        Self::Output: Handler<In, Out = Out>,
11        In: Send + Sync + 'static,
12        Out: Send + Sync + 'static,
13        E: Handler<In, Out = Out>,
14        M2: Middleware<In, E3, Output = E> + 'static,
15        E3: Handler<In, Out = Out>,
16    {
17        JoinMiddleware::new(self, other)
18    }
19}
20
21pub struct JoinMiddleware<In, Out, E1, M1, E2, M2, E3>
22where
23    In: Send + Sync + 'static,
24    Out: Send + Sync + 'static,
25    E1: Handler<In, Out = Out>,
26    M1: Middleware<In, E2, Output = E1>,
27    E2: Handler<In, Out = Out>,
28    M2: Middleware<In, E3, Output = E2>,
29    E3: Handler<In, Out = Out>,
30{
31    middleware1: M1,
32    middleware2: M2,
33    phantom1: PhantomData<In>,
34    phantom2: PhantomData<Out>,
35    phantom3: PhantomData<E1>,
36    phantom4: PhantomData<E2>,
37    phantom5: PhantomData<E3>,
38}
39
40impl<In, Out, E1, M1, E2, M2, E3> Middleware<In, E3> for JoinMiddleware<In, Out, E1, M1, E2, M2, E3>
41where
42    In: Send + Sync + 'static,
43    Out: Send + Sync + 'static,
44    E1: Handler<In, Out = Out>,
45    M1: Middleware<In, E2, Output = E1>,
46    E2: Handler<In, Out = Out>,
47    M2: Middleware<In, E3, Output = E2>,
48    E3: Handler<In, Out = Out>,
49{
50    type Output = E1;
51
52    fn transform(self, handler: E3) -> Self::Output {
53        self.middleware1
54            .transform(self.middleware2.transform(handler))
55    }
56}
57
58impl<In, Out, E1, M1, E2, M2, E3> JoinMiddleware<In, Out, E1, M1, E2, M2, E3>
59where
60    In: Send + Sync + 'static,
61    Out: Send + Sync + 'static,
62    E1: Handler<In, Out = Out>,
63    M1: Middleware<In, E2, Output = E1>,
64    E2: Handler<In, Out = Out>,
65    M2: Middleware<In, E3, Output = E2>,
66    E3: Handler<In, Out = Out>,
67{
68    pub fn new(middleware1: M1, middleware2: M2) -> JoinMiddleware<In, Out, E1, M1, E2, M2, E3> {
69        JoinMiddleware {
70            middleware1: middleware1,
71            middleware2: middleware2,
72            phantom1: PhantomData,
73            phantom2: PhantomData,
74            phantom3: PhantomData,
75            phantom4: PhantomData,
76            phantom5: PhantomData,
77        }
78    }
79}
tihu/middleware.rs

tihu/
middleware.rs
