From 62ffe5f3894723c00ab651e3d6816ee5b48966a0 Mon Sep 17 00:00:00 2001
From: Ali MJ Al-Nasrawy <alimjalnasrawy@gmail.com>
Date: Sun, 5 Dec 2021 01:30:04 +0300
Subject: [PATCH] fix auto-traits for service types (#397)

---
 actix-service/CHANGES.md           |  3 ++
 actix-service/src/apply.rs         |  6 ++--
 actix-service/src/fn_service.rs    | 44 +++++++++++++++++++++++++++---
 actix-service/src/map.rs           |  4 +--
 actix-service/src/map_config.rs    |  4 +--
 actix-service/src/map_err.rs       |  4 +--
 actix-service/src/map_init_err.rs  |  2 +-
 actix-service/src/pipeline.rs      |  4 +--
 actix-service/src/transform_err.rs |  2 +-
 9 files changed, 56 insertions(+), 17 deletions(-)

diff --git a/actix-service/CHANGES.md b/actix-service/CHANGES.md
index c87e2470..bc7e69df 100644
--- a/actix-service/CHANGES.md
+++ b/actix-service/CHANGES.md
@@ -1,6 +1,9 @@
 # Changes
 
 ## Unreleased - 2021-xx-xx
+* Service types can now be `Send` and `'static` regardless of request, response, and config types, etc.. [#397]
+
+[#397]: https://github.com/actix/actix-net/pull/397
 
 
 ## 2.0.1 - 2021-10-11
diff --git a/actix-service/src/apply.rs b/actix-service/src/apply.rs
index 2f798fd0..c77f4242 100644
--- a/actix-service/src/apply.rs
+++ b/actix-service/src/apply.rs
@@ -51,7 +51,7 @@ where
 {
     service: S,
     wrap_fn: F,
-    _phantom: PhantomData<(Req, In, Res, Err)>,
+    _phantom: PhantomData<fn(Req) -> (In, Res, Err)>,
 }
 
 impl<S, F, Fut, Req, In, Res, Err> Apply<S, F, Req, In, Res, Err>
@@ -106,7 +106,7 @@ where
 pub struct ApplyFactory<SF, F, Req, In, Res, Err> {
     factory: SF,
     wrap_fn: F,
-    _phantom: PhantomData<(Req, In, Res, Err)>,
+    _phantom: PhantomData<fn(Req) -> (In, Res, Err)>,
 }
 
 impl<SF, F, Fut, Req, In, Res, Err> ApplyFactory<SF, F, Req, In, Res, Err>
@@ -171,7 +171,7 @@ pin_project! {
         #[pin]
         fut: SF::Future,
         wrap_fn: Option<F>,
-        _phantom: PhantomData<(Req, Res)>,
+        _phantom: PhantomData<fn(Req) -> Res>,
     }
 }
 
diff --git a/actix-service/src/fn_service.rs b/actix-service/src/fn_service.rs
index f83ef81f..ae22e39b 100644
--- a/actix-service/src/fn_service.rs
+++ b/actix-service/src/fn_service.rs
@@ -105,7 +105,7 @@ where
     Fut: Future<Output = Result<Res, Err>>,
 {
     f: F,
-    _t: PhantomData<Req>,
+    _t: PhantomData<fn(Req)>,
 }
 
 impl<F, Fut, Req, Res, Err> FnService<F, Fut, Req, Res, Err>
@@ -160,7 +160,7 @@ where
     Fut: Future<Output = Result<Res, Err>>,
 {
     f: F,
-    _t: PhantomData<(Req, Cfg)>,
+    _t: PhantomData<fn(Req, Cfg)>,
 }
 
 impl<F, Fut, Req, Res, Err, Cfg> FnServiceFactory<F, Fut, Req, Res, Err, Cfg>
@@ -237,7 +237,7 @@ where
     Srv: Service<Req>,
 {
     f: F,
-    _t: PhantomData<(Fut, Cfg, Req, Srv, Err)>,
+    _t: PhantomData<fn(Cfg, Req) -> (Fut, Srv, Err)>,
 }
 
 impl<F, Fut, Cfg, Srv, Req, Err> FnServiceConfig<F, Fut, Cfg, Srv, Req, Err>
@@ -293,7 +293,7 @@ where
     Fut: Future<Output = Result<Srv, Err>>,
 {
     f: F,
-    _t: PhantomData<(Cfg, Req)>,
+    _t: PhantomData<fn(Cfg, Req)>,
 }
 
 impl<F, Cfg, Srv, Req, Fut, Err> FnServiceNoConfig<F, Cfg, Srv, Req, Fut, Err>
@@ -391,4 +391,40 @@ mod tests {
         assert!(res.is_ok());
         assert_eq!(res.unwrap(), ("srv", 1));
     }
+
+    #[actix_rt::test]
+    async fn test_auto_impl_send() {
+        use crate::{map_config, ServiceExt, ServiceFactoryExt};
+        use alloc::rc::Rc;
+
+        let srv_1 = fn_service(|_: Rc<u8>| ok::<_, Rc<u8>>(Rc::new(0u8)));
+
+        let fac_1 = fn_factory_with_config(|_: Rc<u8>| {
+            ok::<_, Rc<u8>>(fn_service(|_: Rc<u8>| ok::<_, Rc<u8>>(Rc::new(0u8))))
+        });
+
+        let fac_2 = fn_factory(|| {
+            ok::<_, Rc<u8>>(fn_service(|_: Rc<u8>| ok::<_, Rc<u8>>(Rc::new(0u8))))
+        });
+
+        fn is_send<T: Send + Sync + Clone>(_: &T) {}
+
+        is_send(&fac_1);
+        is_send(&map_config(fac_1.clone(), |_: Rc<u8>| Rc::new(0u8)));
+        is_send(&fac_1.clone().map_err(|_| Rc::new(0u8)));
+        is_send(&fac_1.clone().map(|_| Rc::new(0u8)));
+        is_send(&fac_1.clone().map_init_err(|_| Rc::new(0u8)));
+        // `and_then` is always !Send
+        // is_send(&fac_1.clone().and_then(fac_1.clone()));
+        is_send(&fac_1.new_service(Rc::new(0u8)).await.unwrap());
+
+        is_send(&fac_2);
+        is_send(&fac_2.new_service(Rc::new(0u8)).await.unwrap());
+
+        is_send(&srv_1);
+        is_send(&ServiceExt::map(srv_1.clone(), |_| Rc::new(0u8)));
+        is_send(&ServiceExt::map_err(srv_1.clone(), |_| Rc::new(0u8)));
+        // `and_then` is always !Send
+        // is_send(&ServiceExt::and_then(srv_1.clone(), srv_1.clone()));
+    }
 }
diff --git a/actix-service/src/map.rs b/actix-service/src/map.rs
index 12fd4395..985a5433 100644
--- a/actix-service/src/map.rs
+++ b/actix-service/src/map.rs
@@ -15,7 +15,7 @@ use super::{Service, ServiceFactory};
 pub struct Map<A, F, Req, Res> {
     service: A,
     f: F,
-    _t: PhantomData<(Req, Res)>,
+    _t: PhantomData<fn(Req) -> Res>,
 }
 
 impl<A, F, Req, Res> Map<A, F, Req, Res> {
@@ -107,7 +107,7 @@ where
 pub struct MapServiceFactory<A, F, Req, Res> {
     a: A,
     f: F,
-    r: PhantomData<(Res, Req)>,
+    r: PhantomData<fn(Req) -> Res>,
 }
 
 impl<A, F, Req, Res> MapServiceFactory<A, F, Req, Res> {
diff --git a/actix-service/src/map_config.rs b/actix-service/src/map_config.rs
index 1297f7a0..5b63e3ad 100644
--- a/actix-service/src/map_config.rs
+++ b/actix-service/src/map_config.rs
@@ -28,7 +28,7 @@ where
 pub struct MapConfig<SF, Req, F, Cfg> {
     factory: SF,
     cfg_mapper: F,
-    e: PhantomData<(Cfg, Req)>,
+    e: PhantomData<fn(Cfg, Req)>,
 }
 
 impl<SF, Req, F, Cfg> MapConfig<SF, Req, F, Cfg> {
@@ -82,7 +82,7 @@ where
 /// `unit_config()` config combinator
 pub struct UnitConfig<SF, Cfg, Req> {
     factory: SF,
-    _phantom: PhantomData<(Cfg, Req)>,
+    _phantom: PhantomData<fn(Cfg, Req)>,
 }
 
 impl<SF, Cfg, Req> UnitConfig<SF, Cfg, Req>
diff --git a/actix-service/src/map_err.rs b/actix-service/src/map_err.rs
index aad0f421..3ce6f418 100644
--- a/actix-service/src/map_err.rs
+++ b/actix-service/src/map_err.rs
@@ -15,7 +15,7 @@ use super::{Service, ServiceFactory};
 pub struct MapErr<S, Req, F, E> {
     service: S,
     mapper: F,
-    _t: PhantomData<(E, Req)>,
+    _t: PhantomData<fn(Req) -> E>,
 }
 
 impl<S, Req, F, E> MapErr<S, Req, F, E> {
@@ -111,7 +111,7 @@ where
 {
     a: SF,
     f: F,
-    e: PhantomData<(E, Req)>,
+    e: PhantomData<fn(Req) -> E>,
 }
 
 impl<SF, Req, F, E> MapErrServiceFactory<SF, Req, F, E>
diff --git a/actix-service/src/map_init_err.rs b/actix-service/src/map_init_err.rs
index 9fc383aa..a8a22a78 100644
--- a/actix-service/src/map_init_err.rs
+++ b/actix-service/src/map_init_err.rs
@@ -13,7 +13,7 @@ use super::ServiceFactory;
 pub struct MapInitErr<A, F, Req, Err> {
     a: A,
     f: F,
-    e: PhantomData<(Req, Err)>,
+    e: PhantomData<fn(Req) -> Err>,
 }
 
 impl<A, F, Req, Err> MapInitErr<A, F, Req, Err>
diff --git a/actix-service/src/pipeline.rs b/actix-service/src/pipeline.rs
index 2c71a74b..2617d0ed 100644
--- a/actix-service/src/pipeline.rs
+++ b/actix-service/src/pipeline.rs
@@ -40,7 +40,7 @@ where
 /// Pipeline service - pipeline allows to compose multiple service into one service.
 pub(crate) struct Pipeline<S, Req> {
     service: S,
-    _phantom: PhantomData<Req>,
+    _phantom: PhantomData<fn(Req)>,
 }
 
 impl<S, Req> Pipeline<S, Req>
@@ -162,7 +162,7 @@ impl<S: Service<Req>, Req> Service<Req> for Pipeline<S, Req> {
 /// Pipeline factory
 pub(crate) struct PipelineFactory<SF, Req> {
     factory: SF,
-    _phantom: PhantomData<Req>,
+    _phantom: PhantomData<fn(Req)>,
 }
 
 impl<SF, Req> PipelineFactory<SF, Req>
diff --git a/actix-service/src/transform_err.rs b/actix-service/src/transform_err.rs
index b4695d5c..b6225a38 100644
--- a/actix-service/src/transform_err.rs
+++ b/actix-service/src/transform_err.rs
@@ -14,7 +14,7 @@ use super::Transform;
 pub struct TransformMapInitErr<T, S, Req, F, E> {
     transform: T,
     mapper: F,
-    _phantom: PhantomData<(S, Req, E)>,
+    _phantom: PhantomData<fn(Req) -> (S, E)>,
 }
 
 impl<T, S, F, E, Req> TransformMapInitErr<T, S, Req, F, E> {