Files
axum/src/routing.rs
T

614 lines
17 KiB
Rust

use crate::{body::BoxBody, response::IntoResponse, ResultExt};
use bytes::Bytes;
use futures_util::{future, ready};
use http::{Method, Request, Response, StatusCode, Uri};
use http_body::Full;
use hyper::Body;
use itertools::Itertools;
use pin_project::pin_project;
use regex::Regex;
use std::{
borrow::Cow,
convert::Infallible,
future::Future,
pin::Pin,
sync::Arc,
task::{Context, Poll},
};
use tower::{
buffer::Buffer,
util::{BoxService, Oneshot, ServiceExt},
BoxError, Layer, Service, ServiceBuilder,
};
// ===== DSL =====
#[derive(Debug, Copy, Clone)]
pub enum MethodFilter {
Any,
Connect,
Delete,
Get,
Head,
Options,
Patch,
Post,
Put,
Trace,
}
impl MethodFilter {
#[allow(clippy::match_like_matches_macro)]
pub(crate) fn matches(self, method: &Method) -> bool {
match (self, method) {
(MethodFilter::Any, _)
| (MethodFilter::Connect, &Method::CONNECT)
| (MethodFilter::Delete, &Method::DELETE)
| (MethodFilter::Get, &Method::GET)
| (MethodFilter::Head, &Method::HEAD)
| (MethodFilter::Options, &Method::OPTIONS)
| (MethodFilter::Patch, &Method::PATCH)
| (MethodFilter::Post, &Method::POST)
| (MethodFilter::Put, &Method::PUT)
| (MethodFilter::Trace, &Method::TRACE) => true,
_ => false,
}
}
}
#[derive(Clone)]
pub struct Route<S, F> {
pub(crate) pattern: PathPattern,
pub(crate) svc: S,
pub(crate) fallback: F,
}
pub trait RoutingDsl: Sized {
fn route<T>(self, spec: &str, svc: T) -> Route<T, Self>
where
T: Service<Request<Body>, Error = Infallible> + Clone,
{
Route {
pattern: PathPattern::new(spec),
svc,
fallback: self,
}
}
fn nest<T>(self, spec: &str, svc: T) -> Nested<T, Self>
where
T: Service<Request<Body>, Error = Infallible> + Clone,
{
Nested {
pattern: PathPattern::new(spec),
svc,
fallback: self,
}
}
fn boxed<B>(self) -> BoxRoute<B>
where
Self: Service<Request<Body>, Response = Response<B>, Error = Infallible> + Send + 'static,
<Self as Service<Request<Body>>>::Future: Send,
B: http_body::Body<Data = Bytes> + Send + Sync + 'static,
B::Error: Into<BoxError> + Send + Sync + 'static,
{
ServiceBuilder::new()
.layer_fn(BoxRoute)
.buffer(1024)
.layer(BoxService::layer())
.service(self)
}
fn layer<L>(self, layer: L) -> Layered<L::Service>
where
L: Layer<Self>,
L::Service: Service<Request<Body>> + Clone,
{
Layered(layer.layer(self))
}
}
impl<S, F> RoutingDsl for Route<S, F> {}
// ===== Routing service impls =====
impl<S, F, SB, FB> Service<Request<Body>> for Route<S, F>
where
S: Service<Request<Body>, Response = Response<SB>, Error = Infallible> + Clone,
SB: http_body::Body<Data = Bytes> + Send + Sync + 'static,
SB::Error: Into<BoxError>,
F: Service<Request<Body>, Response = Response<FB>, Error = Infallible> + Clone,
FB: http_body::Body<Data = Bytes> + Send + Sync + 'static,
FB::Error: Into<BoxError>,
{
type Response = Response<BoxBody>;
type Error = Infallible;
#[allow(clippy::type_complexity)]
type Future = future::Either<
BoxResponseBody<Oneshot<S, Request<Body>>>,
BoxResponseBody<Oneshot<F, Request<Body>>>,
>;
fn poll_ready(&mut self, _cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
Poll::Ready(Ok(()))
}
fn call(&mut self, mut req: Request<Body>) -> Self::Future {
if let Some(captures) = self.pattern.full_match(req.uri().path()) {
insert_url_params(&mut req, captures);
let response_future = self.svc.clone().oneshot(req);
future::Either::Left(BoxResponseBody(response_future))
} else {
let response_future = self.fallback.clone().oneshot(req);
future::Either::Right(BoxResponseBody(response_future))
}
}
}
#[derive(Debug)]
pub(crate) struct UrlParams(pub(crate) Vec<(String, String)>);
fn insert_url_params<B>(req: &mut Request<B>, params: Vec<(String, String)>) {
if let Some(current) = req.extensions_mut().get_mut::<Option<UrlParams>>() {
let mut current = current.take().unwrap();
current.0.extend(params);
req.extensions_mut().insert(Some(current));
} else {
req.extensions_mut().insert(Some(UrlParams(params)));
}
}
#[pin_project]
pub struct BoxResponseBody<F>(#[pin] pub(crate) F);
impl<F, B> Future for BoxResponseBody<F>
where
F: Future<Output = Result<Response<B>, Infallible>>,
B: http_body::Body<Data = Bytes> + Send + Sync + 'static,
B::Error: Into<BoxError>,
{
type Output = Result<Response<BoxBody>, Infallible>;
fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
let response: Response<B> = ready!(self.project().0.poll(cx)).unwrap_infallible();
let response = response.map(|body| {
let body = body.map_err(Into::into);
BoxBody::new(body)
});
Poll::Ready(Ok(response))
}
}
#[derive(Clone, Copy)]
pub struct EmptyRouter;
impl RoutingDsl for EmptyRouter {}
impl<R> Service<R> for EmptyRouter {
type Response = Response<Body>;
type Error = Infallible;
type Future = future::Ready<Result<Self::Response, Self::Error>>;
fn poll_ready(&mut self, _cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
Poll::Ready(Ok(()))
}
fn call(&mut self, _req: R) -> Self::Future {
let mut res = Response::new(Body::empty());
*res.status_mut() = StatusCode::NOT_FOUND;
future::ok(res)
}
}
// ===== PathPattern =====
#[derive(Debug, Clone)]
pub(crate) struct PathPattern(Arc<Inner>);
#[derive(Debug)]
struct Inner {
full_path_regex: Regex,
capture_group_names: Box<[Bytes]>,
}
impl PathPattern {
pub(crate) fn new(pattern: &str) -> Self {
let mut capture_group_names = Vec::new();
let pattern = pattern
.split('/')
.map(|part| {
if let Some(key) = part.strip_prefix(':') {
capture_group_names.push(Bytes::copy_from_slice(key.as_bytes()));
Cow::Owned(format!("(?P<{}>[^/]*)", key))
} else {
Cow::Borrowed(part)
}
})
.join("/");
let full_path_regex =
Regex::new(&format!("^{}", pattern)).expect("invalid regex generated from route");
Self(Arc::new(Inner {
full_path_regex,
capture_group_names: capture_group_names.into(),
}))
}
pub(crate) fn full_match(&self, path: &str) -> Option<Captures> {
self.do_match(path).and_then(|match_| {
if match_.full_match {
Some(match_.captures)
} else {
None
}
})
}
pub(crate) fn prefix_match<'a>(&self, path: &'a str) -> Option<(&'a str, Captures)> {
self.do_match(path)
.map(|match_| (match_.matched, match_.captures))
}
fn do_match<'a>(&self, path: &'a str) -> Option<Match<'a>> {
self.0.full_path_regex.captures(path).map(|captures| {
let matched = captures.get(0).unwrap();
let full_match = matched.as_str() == path;
let captures = self
.0
.capture_group_names
.iter()
.map(|bytes| {
std::str::from_utf8(bytes)
.expect("bytes were created from str so is valid utf-8")
})
.filter_map(|name| captures.name(name).map(|value| (name, value.as_str())))
.map(|(key, value)| (key.to_string(), value.to_string()))
.collect::<Vec<_>>();
Match {
captures,
full_match,
matched: matched.as_str(),
}
})
}
}
struct Match<'a> {
captures: Captures,
// true if regex matched whole path, false if it only matched a prefix
full_match: bool,
matched: &'a str,
}
type Captures = Vec<(String, String)>;
// ===== BoxRoute =====
pub struct BoxRoute<B>(Buffer<BoxService<Request<Body>, Response<B>, Infallible>, Request<Body>>);
impl<B> Clone for BoxRoute<B> {
fn clone(&self) -> Self {
Self(self.0.clone())
}
}
impl<B> RoutingDsl for BoxRoute<B> {}
impl<B> Service<Request<Body>> for BoxRoute<B>
where
B: http_body::Body<Data = Bytes> + Send + Sync + 'static,
B::Error: Into<BoxError> + Send + Sync + 'static,
{
type Response = Response<BoxBody>;
type Error = Infallible;
type Future = BoxRouteResponseFuture<B>;
#[inline]
fn poll_ready(&mut self, _cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
Poll::Ready(Ok(()))
}
#[inline]
fn call(&mut self, req: Request<Body>) -> Self::Future {
BoxRouteResponseFuture(self.0.clone().oneshot(req))
}
}
#[pin_project]
pub struct BoxRouteResponseFuture<B>(#[pin] InnerFuture<B>);
type InnerFuture<B> = Oneshot<
Buffer<BoxService<Request<Body>, Response<B>, Infallible>, Request<Body>>,
Request<Body>,
>;
impl<B> Future for BoxRouteResponseFuture<B>
where
B: http_body::Body<Data = Bytes> + Send + Sync + 'static,
B::Error: Into<BoxError> + Send + Sync + 'static,
{
type Output = Result<Response<BoxBody>, Infallible>;
fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
match ready!(self.project().0.poll(cx)) {
Ok(res) => Poll::Ready(Ok(res.map(BoxBody::new))),
Err(err) => Poll::Ready(Ok(handle_buffer_error(err))),
}
}
}
fn handle_buffer_error(error: BoxError) -> Response<BoxBody> {
use tower::buffer::error::{Closed, ServiceError};
let error = match error.downcast::<Closed>() {
Ok(closed) => {
return Response::builder()
.status(StatusCode::INTERNAL_SERVER_ERROR)
.body(BoxBody::new(Full::from(closed.to_string())))
.unwrap();
}
Err(e) => e,
};
let error = match error.downcast::<ServiceError>() {
Ok(service_error) => {
return Response::builder()
.status(StatusCode::INTERNAL_SERVER_ERROR)
.body(BoxBody::new(Full::from(format!("Service error: {}. This is a bug in tower-web. All inner services should be infallible. Please file an issue", service_error))))
.unwrap();
}
Err(e) => e,
};
Response::builder()
.status(StatusCode::INTERNAL_SERVER_ERROR)
.body(BoxBody::new(Full::from(format!(
"Uncountered an unknown error: {}. This should never happen. Please file an issue",
error
))))
.unwrap()
}
// ===== Layered =====
#[derive(Clone, Debug)]
pub struct Layered<S>(S);
impl<S> RoutingDsl for Layered<S> {}
impl<S> Layered<S> {
pub fn handle_error<F, B, Res>(self, f: F) -> HandleError<S, F>
where
S: Service<Request<Body>, Response = Response<B>> + Clone,
F: FnOnce(S::Error) -> Res,
Res: IntoResponse,
B: http_body::Body<Data = Bytes> + Send + Sync + 'static,
B::Error: Into<BoxError> + Send + Sync + 'static,
{
HandleError { inner: self.0, f }
}
}
impl<S, B> Service<Request<Body>> for Layered<S>
where
S: Service<Request<Body>, Response = Response<B>, Error = Infallible>,
{
type Response = S::Response;
type Error = Infallible;
type Future = S::Future;
#[inline]
fn poll_ready(&mut self, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
self.0.poll_ready(cx)
}
#[inline]
fn call(&mut self, req: Request<Body>) -> Self::Future {
self.0.call(req)
}
}
#[derive(Clone, Copy)]
pub struct HandleError<S, F> {
inner: S,
f: F,
}
impl<S, F> RoutingDsl for HandleError<S, F> {}
impl<S, F, B, Res> Service<Request<Body>> for HandleError<S, F>
where
S: Service<Request<Body>, Response = Response<B>> + Clone,
F: FnOnce(S::Error) -> Res + Clone,
Res: IntoResponse,
B: http_body::Body<Data = Bytes> + Send + Sync + 'static,
B::Error: Into<BoxError> + Send + Sync + 'static,
{
type Response = Response<BoxBody>;
type Error = Infallible;
type Future = HandleErrorFuture<Oneshot<S, Request<Body>>, F>;
fn poll_ready(&mut self, _cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
Poll::Ready(Ok(()))
}
fn call(&mut self, req: Request<Body>) -> Self::Future {
HandleErrorFuture {
inner: self.inner.clone().oneshot(req),
f: Some(self.f.clone()),
}
}
}
#[pin_project]
pub struct HandleErrorFuture<Fut, F> {
#[pin]
inner: Fut,
f: Option<F>,
}
impl<Fut, F, B, E, Res> Future for HandleErrorFuture<Fut, F>
where
Fut: Future<Output = Result<Response<B>, E>>,
F: FnOnce(E) -> Res,
Res: IntoResponse,
B: http_body::Body<Data = Bytes> + Send + Sync + 'static,
B::Error: Into<BoxError> + Send + Sync + 'static,
{
type Output = Result<Response<BoxBody>, Infallible>;
fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
let this = self.project();
match ready!(this.inner.poll(cx)) {
Ok(res) => Ok(res.map(BoxBody::new)).into(),
Err(err) => {
let f = this.f.take().unwrap();
let res = f(err).into_response();
Ok(res.map(BoxBody::new)).into()
}
}
}
}
// ===== nesting =====
pub fn nest<S>(spec: &str, svc: S) -> Nested<S, EmptyRouter>
where
S: Service<Request<Body>, Error = Infallible> + Clone,
{
Nested {
pattern: PathPattern::new(spec),
svc,
fallback: EmptyRouter,
}
}
#[derive(Debug, Clone)]
pub struct Nested<S, F> {
pattern: PathPattern,
svc: S,
fallback: F,
}
impl<S, F> RoutingDsl for Nested<S, F> {}
impl<S, F, SB, FB> Service<Request<Body>> for Nested<S, F>
where
S: Service<Request<Body>, Response = Response<SB>, Error = Infallible> + Clone,
SB: http_body::Body<Data = Bytes> + Send + Sync + 'static,
SB::Error: Into<BoxError>,
F: Service<Request<Body>, Response = Response<FB>, Error = Infallible> + Clone,
FB: http_body::Body<Data = Bytes> + Send + Sync + 'static,
FB::Error: Into<BoxError>,
{
type Response = Response<BoxBody>;
type Error = Infallible;
#[allow(clippy::type_complexity)]
type Future = future::Either<
BoxResponseBody<Oneshot<S, Request<Body>>>,
BoxResponseBody<Oneshot<F, Request<Body>>>,
>;
fn poll_ready(&mut self, _cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
Poll::Ready(Ok(()))
}
fn call(&mut self, mut req: Request<Body>) -> Self::Future {
if let Some((prefix, captures)) = self.pattern.prefix_match(req.uri().path()) {
let without_prefix = strip_prefix(req.uri(), prefix);
*req.uri_mut() = without_prefix;
insert_url_params(&mut req, captures);
let response_future = self.svc.clone().oneshot(req);
future::Either::Left(BoxResponseBody(response_future))
} else {
let response_future = self.fallback.clone().oneshot(req);
future::Either::Right(BoxResponseBody(response_future))
}
}
}
fn strip_prefix(uri: &Uri, prefix: &str) -> Uri {
let path_and_query = if let Some(path_and_query) = uri.path_and_query() {
let new_path = if let Some(path) = path_and_query.path().strip_prefix(prefix) {
path
} else {
path_and_query.path()
};
if let Some(query) = path_and_query.query() {
Some(
format!("{}?{}", new_path, query)
.parse::<http::uri::PathAndQuery>()
.unwrap(),
)
} else {
Some(new_path.parse().unwrap())
}
} else {
None
};
let mut parts = http::uri::Parts::default();
parts.scheme = uri.scheme().cloned();
parts.authority = uri.authority().cloned();
parts.path_and_query = path_and_query;
Uri::from_parts(parts).unwrap()
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_routing() {
assert_match("/", "/");
assert_match("/foo", "/foo");
assert_match("/foo/", "/foo/");
refute_match("/foo", "/foo/");
refute_match("/foo/", "/foo");
assert_match("/foo/bar", "/foo/bar");
refute_match("/foo/bar/", "/foo/bar");
refute_match("/foo/bar", "/foo/bar/");
assert_match("/:value", "/foo");
assert_match("/users/:id", "/users/1");
assert_match("/users/:id/action", "/users/42/action");
refute_match("/users/:id/action", "/users/42");
refute_match("/users/:id", "/users/42/action");
}
fn assert_match(route_spec: &'static str, path: &'static str) {
let route = PathPattern::new(route_spec);
assert!(
route.full_match(path).is_some(),
"`{}` doesn't match `{}`",
path,
route_spec
);
}
fn refute_match(route_spec: &'static str, path: &'static str) {
let route = PathPattern::new(route_spec);
assert!(
route.full_match(path).is_none(),
"`{}` did match `{}` (but shouldn't)",
path,
route_spec
);
}
}