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Diffstat (limited to 'third_party/rust/hyper/src/service/make.rs')
-rw-r--r-- | third_party/rust/hyper/src/service/make.rs | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/third_party/rust/hyper/src/service/make.rs b/third_party/rust/hyper/src/service/make.rs new file mode 100644 index 0000000000..63e6f298f1 --- /dev/null +++ b/third_party/rust/hyper/src/service/make.rs @@ -0,0 +1,187 @@ +use std::error::Error as StdError; +use std::fmt; + +use tokio::io::{AsyncRead, AsyncWrite}; + +use super::{HttpService, Service}; +use crate::body::HttpBody; +use crate::common::{task, Future, Poll}; + +// The same "trait alias" as tower::MakeConnection, but inlined to reduce +// dependencies. +pub trait MakeConnection<Target>: self::sealed::Sealed<(Target,)> { + type Connection: AsyncRead + AsyncWrite; + type Error; + type Future: Future<Output = Result<Self::Connection, Self::Error>>; + + fn poll_ready(&mut self, cx: &mut task::Context<'_>) -> Poll<Result<(), Self::Error>>; + fn make_connection(&mut self, target: Target) -> Self::Future; +} + +impl<S, Target> self::sealed::Sealed<(Target,)> for S where S: Service<Target> {} + +impl<S, Target> MakeConnection<Target> for S +where + S: Service<Target>, + S::Response: AsyncRead + AsyncWrite, +{ + type Connection = S::Response; + type Error = S::Error; + type Future = S::Future; + + fn poll_ready(&mut self, cx: &mut task::Context<'_>) -> Poll<Result<(), Self::Error>> { + Service::poll_ready(self, cx) + } + + fn make_connection(&mut self, target: Target) -> Self::Future { + Service::call(self, target) + } +} + +// Just a sort-of "trait alias" of `MakeService`, not to be implemented +// by anyone, only used as bounds. +pub trait MakeServiceRef<Target, ReqBody>: self::sealed::Sealed<(Target, ReqBody)> { + type ResBody: HttpBody; + type Error: Into<Box<dyn StdError + Send + Sync>>; + type Service: HttpService<ReqBody, ResBody = Self::ResBody, Error = Self::Error>; + type MakeError: Into<Box<dyn StdError + Send + Sync>>; + type Future: Future<Output = Result<Self::Service, Self::MakeError>>; + + // Acting like a #[non_exhaustive] for associated types of this trait. + // + // Basically, no one outside of hyper should be able to set this type + // or declare bounds on it, so it should prevent people from creating + // trait objects or otherwise writing code that requires using *all* + // of the associated types. + // + // Why? So we can add new associated types to this alias in the future, + // if necessary. + type __DontNameMe: self::sealed::CantImpl; + + fn poll_ready_ref(&mut self, cx: &mut task::Context<'_>) -> Poll<Result<(), Self::MakeError>>; + + fn make_service_ref(&mut self, target: &Target) -> Self::Future; +} + +impl<T, Target, E, ME, S, F, IB, OB> MakeServiceRef<Target, IB> for T +where + T: for<'a> Service<&'a Target, Error = ME, Response = S, Future = F>, + E: Into<Box<dyn StdError + Send + Sync>>, + ME: Into<Box<dyn StdError + Send + Sync>>, + S: HttpService<IB, ResBody = OB, Error = E>, + F: Future<Output = Result<S, ME>>, + IB: HttpBody, + OB: HttpBody, +{ + type Error = E; + type Service = S; + type ResBody = OB; + type MakeError = ME; + type Future = F; + + type __DontNameMe = self::sealed::CantName; + + fn poll_ready_ref(&mut self, cx: &mut task::Context<'_>) -> Poll<Result<(), Self::MakeError>> { + self.poll_ready(cx) + } + + fn make_service_ref(&mut self, target: &Target) -> Self::Future { + self.call(target) + } +} + +impl<T, Target, S, B1, B2> self::sealed::Sealed<(Target, B1)> for T +where + T: for<'a> Service<&'a Target, Response = S>, + S: HttpService<B1, ResBody = B2>, + B1: HttpBody, + B2: HttpBody, +{ +} + +/// Create a `MakeService` from a function. +/// +/// # Example +/// +/// ``` +/// # #[cfg(feature = "runtime")] +/// # async fn run() { +/// use std::convert::Infallible; +/// use hyper::{Body, Request, Response, Server}; +/// use hyper::server::conn::AddrStream; +/// use hyper::service::{make_service_fn, service_fn}; +/// +/// let addr = ([127, 0, 0, 1], 3000).into(); +/// +/// let make_svc = make_service_fn(|socket: &AddrStream| { +/// let remote_addr = socket.remote_addr(); +/// async move { +/// Ok::<_, Infallible>(service_fn(move |_: Request<Body>| async move { +/// Ok::<_, Infallible>( +/// Response::new(Body::from(format!("Hello, {}!", remote_addr))) +/// ) +/// })) +/// } +/// }); +/// +/// // Then bind and serve... +/// let server = Server::bind(&addr) +/// .serve(make_svc); +/// +/// // Finally, spawn `server` onto an Executor... +/// if let Err(e) = server.await { +/// eprintln!("server error: {}", e); +/// } +/// # } +/// # fn main() {} +/// ``` +pub fn make_service_fn<F, Target, Ret>(f: F) -> MakeServiceFn<F> +where + F: FnMut(&Target) -> Ret, + Ret: Future, +{ + MakeServiceFn { f } +} + +/// `MakeService` returned from [`make_service_fn`] +#[derive(Clone, Copy)] +pub struct MakeServiceFn<F> { + f: F, +} + +impl<'t, F, Ret, Target, Svc, MkErr> Service<&'t Target> for MakeServiceFn<F> +where + F: FnMut(&Target) -> Ret, + Ret: Future<Output = Result<Svc, MkErr>>, + MkErr: Into<Box<dyn StdError + Send + Sync>>, +{ + type Error = MkErr; + type Response = Svc; + type Future = Ret; + + fn poll_ready(&mut self, _cx: &mut task::Context<'_>) -> Poll<Result<(), Self::Error>> { + Poll::Ready(Ok(())) + } + + fn call(&mut self, target: &'t Target) -> Self::Future { + (self.f)(target) + } +} + +impl<F> fmt::Debug for MakeServiceFn<F> { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.debug_struct("MakeServiceFn").finish() + } +} + +mod sealed { + pub trait Sealed<X> {} + + #[allow(unreachable_pub)] // This is intentional. + pub trait CantImpl {} + + #[allow(missing_debug_implementations)] + pub enum CantName {} + + impl CantImpl for CantName {} +} |