/rust/registry/src/index.crates.io-1949cf8c6b5b557f/axum-0.8.9/src/routing/route.rs

Source
use crate::{
    body::{Body, HttpBody},
    response::Response,
    util::MapIntoResponse,
};
use axum_core::{extract::Request, response::IntoResponse};
use bytes::Bytes;
use http::{
    header::{self, CONTENT_LENGTH},
    HeaderMap, HeaderValue, Method,
};
use pin_project_lite::pin_project;
use std::{
    convert::Infallible,
    fmt,
    future::Future,
    pin::Pin,
    task::{ready, Context, Poll},
};
use tower::{
    util::{BoxCloneSyncService, MapErrLayer, Oneshot},
    ServiceExt,
};
use tower_layer::Layer;
use tower_service::Service;

/// How routes are stored inside a [`Router`](super::Router).
///
/// You normally shouldn't need to care about this type. It's used in
/// [`Router::layer`](super::Router::layer).
pub struct Route<E = Infallible>(BoxCloneSyncService<Request, Response, E>);

impl<E> Route<E> {
    pub(crate) fn new<T>(svc: T) -> Self
    where
        T: Service<Request, Error = E> + Clone + Send + Sync + 'static,
        T::Response: IntoResponse + 'static,
        T::Future: Send + 'static,
    {
        Self(BoxCloneSyncService::new(MapIntoResponse::new(svc)))
    }

    /// Variant of [`Route::call`] that takes ownership of the route to avoid cloning.
    pub(crate) fn call_owned(self, req: Request<Body>) -> RouteFuture<E> {
        let req = req.map(Body::new);
        self.oneshot_inner_owned(req).not_top_level()
    }

    pub(crate) fn oneshot_inner(&mut self, req: Request) -> RouteFuture<E> {
        let method = req.method().clone();
        RouteFuture::new(method, self.0.clone().oneshot(req))
    }

    /// Variant of [`Route::oneshot_inner`] that takes ownership of the route to avoid cloning.
    pub(crate) fn oneshot_inner_owned(self, req: Request) -> RouteFuture<E> {
        let method = req.method().clone();
        RouteFuture::new(method, self.0.oneshot(req))
    }

    pub(crate) fn layer<L, NewError>(self, layer: L) -> Route<NewError>
    where
        L: Layer<Route<E>> + Clone + Send + 'static,
        L::Service: Service<Request> + Clone + Send + Sync + 'static,
        <L::Service as Service<Request>>::Response: IntoResponse + 'static,
        <L::Service as Service<Request>>::Error: Into<NewError> + 'static,
        <L::Service as Service<Request>>::Future: Send + 'static,
        NewError: 'static,
    {
        let layer = (MapErrLayer::new(Into::into), layer);

        Route::new(layer.layer(self))
    }
}

impl<E> Clone for Route<E> {
    #[track_caller]
    fn clone(&self) -> Self {
        Self(self.0.clone())
    }
}

impl<E> fmt::Debug for Route<E> {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.debug_struct("Route").finish()
    }
}

impl<B, E> Service<Request<B>> for Route<E>
where
    B: HttpBody<Data = bytes::Bytes> + Send + 'static,
    B::Error: Into<axum_core::BoxError>,
{
    type Response = Response;
    type Error = E;
    type Future = RouteFuture<E>;

    #[inline]
    fn poll_ready(&mut self, _cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
        Poll::Ready(Ok(()))
    }

    #[inline]
    fn call(&mut self, req: Request<B>) -> Self::Future {
        self.oneshot_inner(req.map(Body::new)).not_top_level()
    }
}

pin_project! {
    /// Response future for [`Route`].
    pub struct RouteFuture<E> {
        #[pin]
        inner: Oneshot<BoxCloneSyncService<Request, Response, E>, Request>,
        method: Method,
        allow_header: Option<Bytes>,
        top_level: bool,
    }
}

impl<E> RouteFuture<E> {
    fn new(
        method: Method,
        inner: Oneshot<BoxCloneSyncService<Request, Response, E>, Request>,
    ) -> Self {
        Self {
            inner,
            method,
            allow_header: None,
            top_level: true,
        }
    }

    pub(crate) fn allow_header(mut self, allow_header: Bytes) -> Self {
        self.allow_header = Some(allow_header);
        self
    }

    pub(crate) fn not_top_level(mut self) -> Self {
        self.top_level = false;
        self
    }
}

impl<E> Future for RouteFuture<E> {
    type Output = Result<Response, E>;

    #[inline]
    fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
        let this = self.project();
        let mut res = ready!(this.inner.poll(cx))?;

        if *this.method == Method::CONNECT && res.status().is_success() {
            // From https://httpwg.org/specs/rfc9110.html#CONNECT:
            // > A server MUST NOT send any Transfer-Encoding or
            // > Content-Length header fields in a 2xx (Successful)
            // > response to CONNECT.
            if res.headers().contains_key(&CONTENT_LENGTH)
                || res.headers().contains_key(&header::TRANSFER_ENCODING)
                || res.size_hint().lower() != 0
            {
                error!("response to CONNECT with nonempty body");
                res = res.map(|_| Body::empty());
            }
        } else if *this.top_level {
            set_allow_header(res.headers_mut(), this.allow_header);

            // make sure to set content-length before removing the body
            set_content_length(res.size_hint(), res.headers_mut());

            if *this.method == Method::HEAD {
                *res.body_mut() = Body::empty();
            }
        }

        Poll::Ready(Ok(res))
    }
}

fn set_allow_header(headers: &mut HeaderMap, allow_header: &mut Option<Bytes>) {
    match allow_header.take() {
        Some(allow_header) if !headers.contains_key(header::ALLOW) => {
            headers.insert(
                header::ALLOW,
                HeaderValue::from_maybe_shared(allow_header).expect("invalid `Allow` header"),
            );
        }
        _ => {}
    }
}

fn set_content_length(size_hint: http_body::SizeHint, headers: &mut HeaderMap) {
    if headers.contains_key(CONTENT_LENGTH) {
        return;
    }

    if let Some(size) = size_hint.exact() {
        let header_value = if size == 0 {
            #[allow(clippy::declare_interior_mutable_const)]
            const ZERO: HeaderValue = HeaderValue::from_static("0");

            ZERO
        } else {
            let mut buffer = itoa::Buffer::new();
            HeaderValue::from_str(buffer.format(size)).unwrap()
        };

        headers.insert(CONTENT_LENGTH, header_value);
    }
}

pin_project! {
    /// A [`RouteFuture`] that always yields a [`Response`].
    pub struct InfallibleRouteFuture {
        #[pin]
        future: RouteFuture<Infallible>,
    }
}

impl InfallibleRouteFuture {
    pub(crate) fn new(future: RouteFuture<Infallible>) -> Self {
        Self { future }
    }
}

impl Future for InfallibleRouteFuture {
    type Output = Response;

    fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
        match ready!(self.project().future.poll(cx)) {
            Ok(response) => Poll::Ready(response),
            Err(err) => match err {},
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn traits() {
        use crate::test_helpers::*;
        assert_send::<Route<()>>();
    }
}

Coverage Report

Created: 2026-07-13 08:11

Line	Count	Source
1		use crate::{
2		body::{Body, HttpBody},
3		response::Response,
4		util::MapIntoResponse,
5		};
6		use axum_core::{extract::Request, response::IntoResponse};
7		use bytes::Bytes;
8		use http::{
9		header::{self, CONTENT_LENGTH},
10		HeaderMap, HeaderValue, Method,
11		};
12		use pin_project_lite::pin_project;
13		use std::{
14		convert::Infallible,
15		fmt,
16		future::Future,
17		pin::Pin,
18		task::{ready, Context, Poll},
19		};
20		use tower::{
21		util::{BoxCloneSyncService, MapErrLayer, Oneshot},
22		ServiceExt,
23		};
24		use tower_layer::Layer;
25		use tower_service::Service;
26
27		/// How routes are stored inside a [`Router`](super::Router).
28		///
29		/// You normally shouldn't need to care about this type. It's used in
30		/// [`Router::layer`](super::Router::layer).
31		pub struct Route<E = Infallible>(BoxCloneSyncService<Request, Response, E>);
32
33		impl<E> Route<E> {
34	0	pub(crate) fn new<T>(svc: T) -> Self
35	0	where
36	0	T: Service<Request, Error = E> + Clone + Send + Sync + 'static,
37	0	T::Response: IntoResponse + 'static,
38	0	T::Future: Send + 'static,
39		{
40	0	Self(BoxCloneSyncService::new(MapIntoResponse::new(svc)))
41	0	} Unexecuted instantiation: <axum::routing::route::Route>::new::<axum::handler::service::HandlerService<tonic::service::router::unimplemented, ((),), ()>> Unexecuted instantiation: <axum::routing::route::Route>::new::<tower::util::service_fn::ServiceFn<<axum::routing::method_routing::MethodRouter>::new::{closure#0}>> Unexecuted instantiation: <axum::routing::route::Route>::new::<axum::routing::not_found::NotFound> Unexecuted instantiation: <axum::routing::route::Route<_>>::new::<_>
42
43		/// Variant of [`Route::call`] that takes ownership of the route to avoid cloning.
44	0	pub(crate) fn call_owned(self, req: Request<Body>) -> RouteFuture<E> {
45	0	let req = req.map(Body::new);
46	0	self.oneshot_inner_owned(req).not_top_level()
47	0	}
48
49	0	pub(crate) fn oneshot_inner(&mut self, req: Request) -> RouteFuture<E> {
50	0	let method = req.method().clone();
51	0	RouteFuture::new(method, self.0.clone().oneshot(req))
52	0	} Unexecuted instantiation: <axum::routing::route::Route>::oneshot_inner Unexecuted instantiation: <axum::routing::route::Route<_>>::oneshot_inner
53
54		/// Variant of [`Route::oneshot_inner`] that takes ownership of the route to avoid cloning.
55	0	pub(crate) fn oneshot_inner_owned(self, req: Request) -> RouteFuture<E> {
56	0	let method = req.method().clone();
57	0	RouteFuture::new(method, self.0.oneshot(req))
58	0	}
59
60	0	pub(crate) fn layer<L, NewError>(self, layer: L) -> Route<NewError>
61	0	where
62	0	L: Layer<Route<E>> + Clone + Send + 'static,
63	0	L::Service: Service<Request> + Clone + Send + Sync + 'static,
64	0	<L::Service as Service<Request>>::Response: IntoResponse + 'static,
65	0	<L::Service as Service<Request>>::Error: Into<NewError> + 'static,
66	0	<L::Service as Service<Request>>::Future: Send + 'static,
67	0	NewError: 'static,
68		{
69	0	let layer = (MapErrLayer::new(Into::into), layer);
70
71	0	Route::new(layer.layer(self))
72	0	}
73		}
74
75		impl<E> Clone for Route<E> {
76		#[track_caller]
77	0	fn clone(&self) -> Self {
78	0	Self(self.0.clone())
79	0	}
80		}
81
82		impl<E> fmt::Debug for Route<E> {
83	0	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
84	0	f.debug_struct("Route").finish()
85	0	}
86		}
87
88		impl<B, E> Service<Request<B>> for Route<E>
89		where
90		B: HttpBody<Data = bytes::Bytes> + Send + 'static,
91		B::Error: Into<axum_core::BoxError>,
92		{
93		type Response = Response;
94		type Error = E;
95		type Future = RouteFuture<E>;
96
97		#[inline]
98	0	fn poll_ready(&mut self, _cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
99	0	Poll::Ready(Ok(()))
100	0	}
101
102		#[inline]
103	0	fn call(&mut self, req: Request<B>) -> Self::Future {
104	0	self.oneshot_inner(req.map(Body::new)).not_top_level()
105	0	} Unexecuted instantiation: <axum::routing::route::Route as tower_service::Service<http::request::Request<axum_core::body::Body>>>::call Unexecuted instantiation: <axum::routing::route::Route<_> as tower_service::Service<http::request::Request<_>>>::call
106		}
107
108		pin_project! {
109		/// Response future for [`Route`].
110		pub struct RouteFuture<E> {
111		#[pin]
112		inner: Oneshot<BoxCloneSyncService<Request, Response, E>, Request>,
113		method: Method,
114		allow_header: Option<Bytes>,
115		top_level: bool,
116		}
117		}
118
119		impl<E> RouteFuture<E> {
120	0	fn new(
121	0	method: Method,
122	0	inner: Oneshot<BoxCloneSyncService<Request, Response, E>, Request>,
123	0	) -> Self {
124	0	Self {
125	0	inner,
126	0	method,
127	0	allow_header: None,
128	0	top_level: true,
129	0	}
130	0	} Unexecuted instantiation: <axum::routing::route::RouteFuture<core::convert::Infallible>>::new Unexecuted instantiation: <axum::routing::route::RouteFuture<_>>::new
131
132	0	pub(crate) fn allow_header(mut self, allow_header: Bytes) -> Self {
133	0	self.allow_header = Some(allow_header);
134	0	self
135	0	}
136
137	0	pub(crate) fn not_top_level(mut self) -> Self {
138	0	self.top_level = false;
139	0	self
140	0	} Unexecuted instantiation: <axum::routing::route::RouteFuture<core::convert::Infallible>>::not_top_level Unexecuted instantiation: <axum::routing::route::RouteFuture<_>>::not_top_level
141		}
142
143		impl<E> Future for RouteFuture<E> {
144		type Output = Result<Response, E>;
145
146		#[inline]
147	0	fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
148	0	let this = self.project();
149	0	let mut res = ready!(this.inner.poll(cx))?;
150
151	0	if *this.method == Method::CONNECT && res.status().is_success() {
152		// From https://httpwg.org/specs/rfc9110.html#CONNECT:
153		// > A server MUST NOT send any Transfer-Encoding or
154		// > Content-Length header fields in a 2xx (Successful)
155		// > response to CONNECT.
156	0	if res.headers().contains_key(&CONTENT_LENGTH)
157	0	\|\| res.headers().contains_key(&header::TRANSFER_ENCODING)
158	0	\|\| res.size_hint().lower() != 0
159		{
160		error!("response to CONNECT with nonempty body");
161	0	res = res.map(\|_\| Body::empty());
162	0	}
163	0	} else if *this.top_level {
164	0	set_allow_header(res.headers_mut(), this.allow_header);
165
166		// make sure to set content-length before removing the body
167	0	set_content_length(res.size_hint(), res.headers_mut());
168
169	0	if *this.method == Method::HEAD {
170	0	*res.body_mut() = Body::empty();
171	0	}
172	0	}
173
174	0	Poll::Ready(Ok(res))
175	0	}
176		}
177
178	0	fn set_allow_header(headers: &mut HeaderMap, allow_header: &mut Option<Bytes>) {
179	0	match allow_header.take() {
180	0	Some(allow_header) if !headers.contains_key(header::ALLOW) => {
181	0	headers.insert(
182	0	header::ALLOW,
183	0	HeaderValue::from_maybe_shared(allow_header).expect("invalid `Allow` header"),
184	0	);
185	0	}
186	0	_ => {}
187		}
188	0	}
189
190	0	fn set_content_length(size_hint: http_body::SizeHint, headers: &mut HeaderMap) {
191	0	if headers.contains_key(CONTENT_LENGTH) {
192	0	return;
193	0	}
194
195	0	if let Some(size) = size_hint.exact() {
196	0	let header_value = if size == 0 {
197		#[allow(clippy::declare_interior_mutable_const)]
198		const ZERO: HeaderValue = HeaderValue::from_static("0");
199
200	0	ZERO
201		} else {
202	0	let mut buffer = itoa::Buffer::new();
203	0	HeaderValue::from_str(buffer.format(size)).unwrap()
204		};
205
206	0	headers.insert(CONTENT_LENGTH, header_value);
207	0	}
208	0	}
209
210		pin_project! {
211		/// A [`RouteFuture`] that always yields a [`Response`].
212		pub struct InfallibleRouteFuture {
213		#[pin]
214		future: RouteFuture<Infallible>,
215		}
216		}
217
218		impl InfallibleRouteFuture {
219	0	pub(crate) fn new(future: RouteFuture<Infallible>) -> Self {
220	0	Self { future }
221	0	}
222		}
223
224		impl Future for InfallibleRouteFuture {
225		type Output = Response;
226
227	0	fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
228	0	match ready!(self.project().future.poll(cx)) {
229	0	Ok(response) => Poll::Ready(response),
230		Err(err) => match err {},
231		}
232	0	}
233		}
234
235		#[cfg(test)]
236		mod tests {
237		use super::*;
238
239		#[test]
240		fn traits() {
241		use crate::test_helpers::*;
242		assert_send::<Route<()>>();
243		}
244		}