Always store state in an Arc (#1270)

* Add extension and state benchmarks

* wip

* Arc the state everywhere

* don't require `S: Clone`

* fix example

axum-extra/src/handler/mod.rs

@@ -6,7 +6,7 @@ use axum::{
     response::{IntoResponse, Response},
 };
 use futures_util::future::{BoxFuture, FutureExt, Map};
-use std::{future::Future, marker::PhantomData};
+use std::{future::Future, marker::PhantomData, sync::Arc};
 
 mod or;
 
@@ -24,7 +24,11 @@ pub trait HandlerCallWithExtractors<T, S, B>: Sized {
     type Future: Future<Output = Response> + Send + 'static;
 
     /// Call the handler with the extracted inputs.
-    fn call(self, state: S, extractors: T) -> <Self as HandlerCallWithExtractors<T, S, B>>::Future;
+    fn call(
+        self,
+        state: Arc<S>,
+        extractors: T,
+    ) -> <Self as HandlerCallWithExtractors<T, S, B>>::Future;
 
     /// Conver this `HandlerCallWithExtractors` into [`Handler`].
     fn into_handler(self) -> IntoHandler<Self, T, S, B> {
@@ -70,7 +74,7 @@ pub trait HandlerCallWithExtractors<T, S, B>: Sized {
     /// impl<S, B> FromRequest<S, B> for AdminPermissions
     /// where
     ///     B: Send,
-    ///     S: Send,
+    ///     S: Send + Sync,
     /// {
     ///     // check for admin permissions...
     ///     # type Rejection = ();
@@ -85,7 +89,7 @@ pub trait HandlerCallWithExtractors<T, S, B>: Sized {
     /// impl<S, B> FromRequest<S, B> for User
     /// where
     ///     B: Send,
-    ///     S: Send,
+    ///     S: Send + Sync,
     /// {
     ///     // check for a logged in user...
     ///     # type Rejection = ();
@@ -130,7 +134,7 @@ macro_rules! impl_handler_call_with {
 
             fn call(
                 self,
-                _state: S,
+                _state: Arc<S>,
                 ($($ty,)*): ($($ty,)*),
             ) -> <Self as HandlerCallWithExtractors<($($ty,)*), S, B>>::Future {
                 self($($ty,)*).map(IntoResponse::into_response)
@@ -172,13 +176,13 @@ where
     T: FromRequest<S, B> + Send + 'static,
     T::Rejection: Send,
     B: Send + 'static,
-    S: Clone + Send + 'static,
+    S: Send + Sync + 'static,
 {
     type Future = BoxFuture<'static, Response>;
 
-    fn call(self, state: S, req: http::Request<B>) -> Self::Future {
+    fn call(self, state: Arc<S>, req: http::Request<B>) -> Self::Future {
         Box::pin(async move {
-            let mut req = RequestParts::with_state(state.clone(), req);
+            let mut req = RequestParts::with_state_arc(Arc::clone(&state), req);
             match req.extract::<T>().await {
                 Ok(t) => self.handler.call(state, t).await,
                 Err(rejection) => rejection.into_response(),

axum-extra/src/handler/or.rs

@@ -8,7 +8,7 @@ use axum::{
 };
 use futures_util::future::{BoxFuture, Either as EitherFuture, FutureExt, Map};
 use http::StatusCode;
-use std::{future::Future, marker::PhantomData};
+use std::{future::Future, marker::PhantomData, sync::Arc};
 
 /// [`Handler`] that runs one [`Handler`] and if that rejects it'll fallback to another
 /// [`Handler`].
@@ -37,7 +37,7 @@ where
 
     fn call(
         self,
-        state: S,
+        state: Arc<S>,
         extractors: Either<Lt, Rt>,
     ) -> <Self as HandlerCallWithExtractors<Either<Lt, Rt>, S, B>>::Future {
         match extractors {
@@ -64,14 +64,14 @@ where
     Lt::Rejection: Send,
     Rt::Rejection: Send,
     B: Send + 'static,
-    S: Clone + Send + 'static,
+    S: Send + Sync + 'static,
 {
     // this puts `futures_util` in our public API but thats fine in axum-extra
     type Future = BoxFuture<'static, Response>;
 
-    fn call(self, state: S, req: Request<B>) -> Self::Future {
+    fn call(self, state: Arc<S>, req: Request<B>) -> Self::Future {
         Box::pin(async move {
-            let mut req = RequestParts::with_state(state.clone(), req);
+            let mut req = RequestParts::with_state_arc(Arc::clone(&state), req);
 
             if let Ok(lt) = req.extract::<Lt>().await {
                 return self.lhs.call(state, lt).await;