tower_async/util/
map_response.rs

1use std::fmt;
2use tower_async_layer::Layer;
3use tower_async_service::Service;
4
5/// Service returned by the [`map_response`] combinator.
6///
7/// [`map_response`]: crate::util::ServiceExt::map_response
8#[derive(Clone)]
9pub struct MapResponse<S, F> {
10    inner: S,
11    f: F,
12}
13
14impl<S, F> fmt::Debug for MapResponse<S, F>
15where
16    S: fmt::Debug,
17{
18    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
19        f.debug_struct("MapResponse")
20            .field("inner", &self.inner)
21            .field("f", &format_args!("{}", std::any::type_name::<F>()))
22            .finish()
23    }
24}
25
26/// A [`Layer`] that produces a [`MapResponse`] service.
27///
28/// [`Layer`]: tower_async_layer::Layer
29#[derive(Debug, Clone)]
30pub struct MapResponseLayer<F> {
31    f: F,
32}
33
34impl<S, F> MapResponse<S, F> {
35    /// Creates a new `MapResponse` service.
36    pub fn new(inner: S, f: F) -> Self {
37        MapResponse { f, inner }
38    }
39
40    /// Returns a new [`Layer`] that produces [`MapResponse`] services.
41    ///
42    /// This is a convenience function that simply calls [`MapResponseLayer::new`].
43    ///
44    /// [`Layer`]: tower_async_layer::Layer
45    pub fn layer(f: F) -> MapResponseLayer<F> {
46        MapResponseLayer { f }
47    }
48}
49
50impl<S, F, Request, Response> Service<Request> for MapResponse<S, F>
51where
52    S: Service<Request>,
53    F: Fn(S::Response) -> Response,
54{
55    type Response = Response;
56    type Error = S::Error;
57
58    #[inline]
59    async fn call(&self, request: Request) -> Result<Self::Response, Self::Error> {
60        match self.inner.call(request).await {
61            Ok(response) => Ok((self.f)(response)),
62            Err(error) => Err(error),
63        }
64    }
65}
66
67impl<F> MapResponseLayer<F> {
68    /// Creates a new [`MapResponseLayer`] layer.
69    pub fn new(f: F) -> Self {
70        MapResponseLayer { f }
71    }
72}
73
74impl<S, F> Layer<S> for MapResponseLayer<F>
75where
76    F: Clone,
77{
78    type Service = MapResponse<S, F>;
79
80    fn layer(&self, inner: S) -> Self::Service {
81        MapResponse {
82            f: self.f.clone(),
83            inner,
84        }
85    }
86}
tower_async/util/map_response.rs

tower_async/util/
map_response.rs
