Move middleware::from_fn into axum (#719)

* Move `middleware::from_fn` into axum

* changelog

* fix feature

* Rephrase changelog a bit

axum-extra/CHANGELOG.md

@@ -9,9 +9,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - **breaking:** `CachedRejection` has been removed ([#699])
 - **breaking:** `<Cached<T> as FromRequest>::Rejection` is now `T::Rejection`. ([#699])
+- **breaking:** `middleware::from_fn` has been moved into the main axum crate ([#719])
 
 [#666]: https://github.com/tokio-rs/axum/pull/666
 [#699]: https://github.com/tokio-rs/axum/pull/699
+[#719]: https://github.com/tokio-rs/axum/pull/719
 
 # 0.1.2 (13. January, 2021)
 

axum-extra/Cargo.toml

@@ -20,7 +20,7 @@ http = "0.2"
 mime = "0.3"
 pin-project-lite = "0.2"
 tower = { version = "0.4", default_features = false, features = ["util"] }
-tower-http = { version = "0.2", features = ["util", "map-response-body"] }
+tower-http = { version = "0.2", features = ["map-response-body"] }
 tower-layer = "0.3"
 tower-service = "0.3"
 

axum-extra/src/lib.rs

@@ -44,6 +44,5 @@
 #![cfg_attr(test, allow(clippy::float_cmp))]
 
 pub mod extract;
-pub mod middleware;
 pub mod response;
 pub mod routing;

axum-extra/src/middleware/mod.rs

@@ -1,5 +0,0 @@
-//! Additional types for creating middleware.
-
-pub mod middleware_fn;
-
-pub use self::middleware_fn::{from_fn, Next};

axum/CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 # Unreleased
 
+- **added:** `middleware::from_fn` for creating middleware from async functions.
+  This previously lived in axum-extra but has been moved to axum ([#719])
 - **breaking:** `sse::Event` now accepts types implementing `AsRef<str>` instead of `Into<String>`
   as field values.
 - **breaking:** `sse::Event` now panics if a setter method is called twice instead of silently
@@ -54,6 +56,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 [#665]: https://github.com/tokio-rs/axum/pull/665
 [#698]: https://github.com/tokio-rs/axum/pull/698
 [#699]: https://github.com/tokio-rs/axum/pull/699
+[#719]: https://github.com/tokio-rs/axum/pull/719
 
 # 0.4.4 (13. January, 2021)
 

axum/Cargo.toml

@@ -42,7 +42,7 @@ sync_wrapper = "0.1.1"
 tokio = { version = "1", features = ["time"] }
 tokio-util = "0.6"
 tower = { version = "0.4.11", default-features = false, features = ["util", "buffer", "make"] }
-tower-http = { version = "0.2.0", features = ["map-response-body"] }
+tower-http = { version = "0.2.0", features = ["util", "map-response-body"] }
 tower-layer = "0.3"
 tower-service = "0.3"
 

axum/src/lib.rs

@@ -466,6 +466,7 @@ pub mod body;
 pub mod error_handling;
 pub mod extract;
 pub mod handler;
+pub mod middleware;
 pub mod response;
 pub mod routing;
 

axum/src/middleware/from_fn.rs

@@ -1,8 +1,4 @@
-//! Create middleware from async functions.
-//!
-//! See [`from_fn`] for more details.
-
-use axum::{
+use crate::{
     body::{self, Bytes, HttpBody},
     response::{IntoResponse, Response},
     BoxError,
@@ -39,8 +35,8 @@ use tower_service::Service;
 ///     http::{Request, StatusCode},
 ///     routing::get,
 ///     response::IntoResponse,
+///     middleware::{self, Next},
 /// };
-/// use axum_extra::middleware::{self, Next};
 ///
 /// async fn auth<B>(req: Request<B>, next: Next<B>) -> impl IntoResponse {
 ///     let auth_header = req.headers()
@@ -76,8 +72,8 @@ use tower_service::Service;
 ///     http::{Request, StatusCode},
 ///     routing::get,
 ///     response::IntoResponse,
+///     middleware::{self, Next}
 /// };
-/// use axum_extra::middleware::{self, Next};
 ///
 /// #[derive(Clone)]
 /// struct State { /* ... */ }
@@ -109,9 +105,9 @@ use tower_service::Service;
 ///     http::{Request, StatusCode},
 ///     routing::get,
 ///     response::IntoResponse,
+///     middleware::{self, Next},
 ///     AddExtensionLayer,
 /// };
-/// use axum_extra::middleware::{self, Next};
 /// use tower::ServiceBuilder;
 ///
 /// #[derive(Clone)]
@@ -138,37 +134,37 @@ use tower_service::Service;
 ///     );
 /// # let app: Router = app;
 /// ```
-pub fn from_fn<F>(f: F) -> MiddlewareFnLayer<F> {
-    MiddlewareFnLayer { f }
+pub fn from_fn<F>(f: F) -> FromFnLayer<F> {
+    FromFnLayer { f }
 }
 
 /// A [`tower::Layer`] from an async function.
 ///
-/// [`tower::Layer`] is used to apply middleware to [`axum::Router`]s.
+/// [`tower::Layer`] is used to apply middleware to [`Router`](crate::Router)'s.
 ///
 /// Created with [`from_fn`]. See that function for more details.
 #[derive(Clone, Copy)]
-pub struct MiddlewareFnLayer<F> {
+pub struct FromFnLayer<F> {
     f: F,
 }
 
-impl<S, F> Layer<S> for MiddlewareFnLayer<F>
+impl<S, F> Layer<S> for FromFnLayer<F>
 where
     F: Clone,
 {
-    type Service = MiddlewareFn<F, S>;
+    type Service = FromFn<F, S>;
 
     fn layer(&self, inner: S) -> Self::Service {
-        MiddlewareFn {
+        FromFn {
             f: self.f.clone(),
             inner,
         }
     }
 }
 
-impl<F> fmt::Debug for MiddlewareFnLayer<F> {
+impl<F> fmt::Debug for FromFnLayer<F> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.debug_struct("MiddlewareFnLayer")
+        f.debug_struct("FromFnLayer")
             // Write out the type name, without quoting it as `&type_name::<F>()` would
             .field("f", &format_args!("{}", type_name::<F>()))
             .finish()
@@ -179,12 +175,12 @@ impl<F> fmt::Debug for MiddlewareFnLayer<F> {
 ///
 /// Created with [`from_fn`]. See that function for more details.
 #[derive(Clone, Copy)]
-pub struct MiddlewareFn<F, S> {
+pub struct FromFn<F, S> {
     f: F,
     inner: S,
 }
 
-impl<F, Fut, Out, S, ReqBody, ResBody> Service<Request<ReqBody>> for MiddlewareFn<F, S>
+impl<F, Fut, Out, S, ReqBody, ResBody> Service<Request<ReqBody>> for FromFn<F, S>
 where
     F: FnMut(Request<ReqBody>, Next<ReqBody>) -> Fut,
     Fut: Future<Output = Out>,
@@ -221,12 +217,12 @@ where
     }
 }
 
-impl<F, S> fmt::Debug for MiddlewareFn<F, S>
+impl<F, S> fmt::Debug for FromFn<F, S>
 where
     S: fmt::Debug,
 {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.debug_struct("MiddlewareFnLayer")
+        f.debug_struct("FromFnLayer")
             .field("f", &format_args!("{}", type_name::<F>()))
             .field("inner", &self.inner)
             .finish()
@@ -250,14 +246,14 @@ impl<ReqBody> Next<ReqBody> {
 
 impl<ReqBody> fmt::Debug for Next<ReqBody> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.debug_struct("MiddlewareFnLayer")
+        f.debug_struct("FromFnLayer")
             .field("inner", &self.inner)
             .finish()
     }
 }
 
 pin_project! {
-    /// Response future for [`MiddlewareFn`].
+    /// Response future for [`FromFn`].
     pub struct ResponseFuture<F> {
         #[pin]
         inner: F,
@@ -283,7 +279,7 @@ where
 #[cfg(test)]
 mod tests {
     use super::*;
-    use axum::{body::Empty, routing::get, Router};
+    use crate::{body::Empty, routing::get, Router};
     use http::{HeaderMap, StatusCode};
     use tower::ServiceExt;
 

axum/src/middleware/mod.rs

@@ -0,0 +1,5 @@
+//! Utilities for writing middleware
+
+mod from_fn;
+
+pub use self::from_fn::{from_fn, FromFn, FromFnLayer, Next};

examples/print-request-response/src/main.rs

@@ -7,11 +7,11 @@
 use axum::{
     body::{Body, Bytes},
     http::{Request, StatusCode},
+    middleware::{self, Next},
     response::{IntoResponse, Response},
     routing::post,
     Router,
 };
-use axum_extra::middleware::{self, Next};
 use std::net::SocketAddr;
 
 #[tokio::main]

examples/prometheus-metrics/src/main.rs

@@ -7,8 +7,14 @@
 //! cargo run -p example-prometheus-metrics
 //! ```
 
-use axum::{extract::MatchedPath, http::Request, response::IntoResponse, routing::get, Router};
-use axum_extra::middleware::{self, Next};
+use axum::{
+    extract::MatchedPath,
+    http::Request,
+    middleware::{self, Next},
+    response::IntoResponse,
+    routing::get,
+    Router,
+};
 use metrics_exporter_prometheus::{Matcher, PrometheusBuilder, PrometheusHandle};
 use std::{
     future::ready,