rework ReadyService trait.

http-codegen/src/lib.rs

@@ -96,25 +96,27 @@ pub fn middleware_impl(_attr: TokenStream, item: TokenStream) -> TokenStream {
     };
 
     match ready_impl {
-        Some(ReadyImpl { ready_stmts, ready_res_ty}) => {
-            quote! {
-                #base
-
-                impl<#generic_ty> ::xitca_service::ready::ReadyService<#req_ty> for #service_ty
-                #where_clause
-                {
-                    type Ready = #ready_res_ty;
-                    type ReadyFuture<'f> where Self: 'f = impl ::core::future::Future<Output = Result<Self::Ready, Self::Error>>;
-                    #[inline]
-                    fn ready(&self) -> Self::ReadyFuture<'_> {
-                        async move {
-                            #(#ready_stmts)*
-                        }
+        Some(ReadyImpl {
+            ready_stmts,
+            ready_ret_ty: ready_res_ty,
+        }) => quote! {
+            #base
+
+            impl<#generic_ty> ::xitca_service::ready::ReadyService<#req_ty> for #service_ty
+            #where_clause
+            {
+                type Ready = #ready_res_ty;
+                type ReadyFuture<'f> = impl ::core::future::Future<Output = Self::Ready> where Self: 'f ;
+                #[inline]
+                fn ready(&self) -> Self::ReadyFuture<'_> {
+                    async move {
+                        #(#ready_stmts)*
                     }
                 }
-            }.into()
+            }
         }
-        None => base.into()
+        .into(),
+        None => base.into(),
     }
 }
 
@@ -169,18 +171,18 @@ impl<'a> CallImpl<'a> {
 
 struct ReadyImpl<'a> {
     ready_stmts: &'a [Stmt],
-    ready_res_ty: &'a Type,
+    ready_ret_ty: &'a Type,
 }
 
 impl<'a> ReadyImpl<'a> {
     fn try_from_items(items: &'a [ImplItem]) -> Option<Self> {
         find_async_method(items, "ready").map(|ready_impl| {
-            let (ready_res_ty, _) = extract_res_ty(&ready_impl.sig.output);
+            let ready_ret_ty = ready_ret_ty(&ready_impl.sig.output);
             let ready_stmts = &ready_impl.block.stmts;
 
             Self {
                 ready_stmts,
-                ready_res_ty,
+                ready_ret_ty,
             }
         })
     }
@@ -203,7 +205,16 @@ fn extract_res_ty(ret: &ReturnType) -> (&Type, &Type) {
         }
     }
 
-    panic!("new_service method must output Result<Self, <Error>>")
+    panic!("build method must output Result<Self, <Error>>")
+}
+
+// Extract types from a return type of function.
+fn ready_ret_ty(ret: &ReturnType) -> &Type {
+    if let ReturnType::Type(_, ty) = ret {
+        return &*ty;
+    }
+
+    panic!("ready method must output ReadyService::Ready type")
 }
 
 // generate a default PatIdent

http/src/h1/service.rs

@@ -75,10 +75,10 @@ where
     B: Stream<Item = Result<Bytes, BE>>,
 {
     type Ready = S::Ready;
-    type ReadyFuture<'f> = impl Future<Output = Result<Self::Ready, Self::Error>> where Self: 'f;
+    type ReadyFuture<'f> = S::ReadyFuture<'f> where Self: 'f;
 
     #[inline]
     fn ready(&self) -> Self::ReadyFuture<'_> {
-        async move { self.service.ready().await.map_err(HttpServiceError::Service) }
+        self.service.ready()
     }
 }

http/src/h2/service.rs

@@ -109,10 +109,10 @@ where
     BE: fmt::Debug,
 {
     type Ready = S::Ready;
-    type ReadyFuture<'f> = impl Future<Output = Result<Self::Ready, Self::Error>> where Self: 'f;
+    type ReadyFuture<'f> = S::ReadyFuture<'f> where Self: 'f;
 
     #[inline]
     fn ready(&self) -> Self::ReadyFuture<'_> {
-        async move { self.service.ready().await.map_err(HttpServiceError::Service) }
+        self.service.ready()
     }
 }

http/src/h3/service.rs

@@ -52,10 +52,10 @@ where
     BE: fmt::Debug,
 {
     type Ready = S::Ready;
-    type ReadyFuture<'f> = impl Future<Output = Result<Self::Ready, Self::Error>> where Self: 'f;
+    type ReadyFuture<'f> = S::ReadyFuture<'f>;
 
     #[inline]
     fn ready(&self) -> Self::ReadyFuture<'_> {
-        async move { self.service.ready().await.map_err(HttpServiceError::Service) }
+        self.service.ready()
     }
 }

http/src/service.rs

@@ -187,10 +187,10 @@ where
     BE: fmt::Debug,
 {
     type Ready = S::Ready;
-    type ReadyFuture<'f> = impl Future<Output = Result<Self::Ready, Self::Error>> where Self: 'f;
+    type ReadyFuture<'f> = S::ReadyFuture<'f> where Self: 'f;
 
     #[inline]
     fn ready(&self) -> Self::ReadyFuture<'_> {
-        async move { self.service.ready().await.map_err(HttpServiceError::Service) }
+        self.service.ready()
     }
 }

http/src/util/service/context.rs

@@ -174,7 +174,7 @@ where
     S: for<'c, 's> ReadyService<&'c mut Context<'s, Req, C>, Response = Res, Error = Err, Ready = R>,
 {
     type Ready = R;
-    type ReadyFuture<'f> = impl Future<Output = Result<Self::Ready, Self::Error>> where Self: 'f;
+    type ReadyFuture<'f> = impl Future<Output = Self::Ready> where Self: 'f;
 
     #[inline]
     fn ready(&self) -> Self::ReadyFuture<'_> {

http/src/util/service/route.rs

@@ -184,11 +184,11 @@ where
     Req: BorrowReq<http::Method>,
 {
     type Ready = ();
-    type ReadyFuture<'f> = impl Future<Output = Result<Self::Ready, Self::Error>> where Self: 'f;
+    type ReadyFuture<'f> = impl Future<Output = Self::Ready> where Self: 'f;
 
     #[inline]
     fn ready(&self) -> Self::ReadyFuture<'_> {
-        async { Ok(()) }
+        async {}
     }
 }
 

http/src/util/service/router.rs

@@ -124,11 +124,11 @@ where
     Req: BorrowReq<http::Uri>,
 {
     type Ready = ();
-    type ReadyFuture<'f> = impl Future<Output = Result<Self::Ready, Self::Error>> where Self: 'f;
+    type ReadyFuture<'f> = impl Future<Output = Self::Ready> where S: 'f;
 
     #[inline]
     fn ready(&self) -> Self::ReadyFuture<'_> {
-        async { Ok(()) }
+        async {}
     }
 }
 

server/src/worker/mod.rs

@@ -29,8 +29,7 @@ where
 
     tokio::task::spawn_local(async move {
         loop {
-            // TODO: What if service return Error when ready.
-            let ready = service.ready().await.ok();
+            let ready = service.ready().await;
 
             match listener.accept().await {
                 Ok(stream) => {

service/src/ready/and_then.rs

@@ -10,13 +10,13 @@ where
     S1: ReadyService<S::Response, Error = S::Error>,
 {
     type Ready = PipelineT<S::Ready, S1::Ready>;
-    type ReadyFuture<'f> = impl Future<Output = Result<Self::Ready, Self::Error>> where Self: 'f;
+    type ReadyFuture<'f> = impl Future<Output = Self::Ready> where Self: 'f;
 
     fn ready(&self) -> Self::ReadyFuture<'_> {
         async move {
-            let first = self.first.ready().await?;
-            let second = self.second.ready().await?;
-            Ok(PipelineT::new(first, second))
+            let first = self.first.ready().await;
+            let second = self.second.ready().await;
+            PipelineT::new(first, second)
         }
     }
 }

service/src/ready/enclosed_fn.rs

@@ -1,5 +1,3 @@
-use core::future::Future;
-
 use crate::{
     async_closure::AsyncClosure,
     pipeline::{marker::EnclosedFn, PipelineT},
@@ -11,13 +9,12 @@ impl<S, Req, T, Res, Err> ReadyService<Req> for PipelineT<S, T, EnclosedFn>
 where
     S: ReadyService<Req>,
     T: for<'s> AsyncClosure<(&'s S, Req), Output = Result<Res, Err>>,
-    Err: From<S::Error>,
 {
     type Ready = S::Ready;
-    type ReadyFuture<'f> = impl Future<Output = Result<Self::Ready, Self::Error>> where Self: 'f;
+    type ReadyFuture<'f> = S::ReadyFuture<'f> where Self: 'f;
 
     #[inline]
     fn ready(&self) -> Self::ReadyFuture<'_> {
-        async move { self.first.ready().await.map_err(Into::into) }
+        self.first.ready()
     }
 }

service/src/ready/function.rs

@@ -10,10 +10,10 @@ where
     Fut: Future<Output = Result<Res, Err>>,
 {
     type Ready = ();
-    type ReadyFuture<'f> = impl Future<Output = Result<Self::Ready, Self::Error>> where Self: 'f;
+    type ReadyFuture<'f> = impl Future<Output = Self::Ready> where F: 'f;
 
     #[inline]
     fn ready(&self) -> Self::ReadyFuture<'_> {
-        async { Ok(()) }
+        async {}
     }
 }

service/src/ready/map_err.rs

@@ -1,5 +1,3 @@
-use core::future::Future;
-
 use crate::pipeline::{marker::MapErr, PipelineT};
 
 use super::ReadyService;
@@ -10,9 +8,10 @@ where
     F: Fn(S::Error) -> E,
 {
     type Ready = S::Ready;
-    type ReadyFuture<'f> = impl Future<Output = Result<Self::Ready, Self::Error>> where Self: 'f;
+    type ReadyFuture<'f> = S::ReadyFuture<'f> where Self: 'f;
 
+    #[inline]
     fn ready(&self) -> Self::ReadyFuture<'_> {
-        async move { self.first.ready().await.map_err(&self.second) }
+        self.first.ready()
     }
 }

service/src/ready/mod.rs

@@ -44,8 +44,8 @@ use super::service::Service;
 /// }
 ///
 /// impl ReadyService<()> for Foo {
-///     type Ready = Permit;
-///     type ReadyFuture<'f> = impl Future<Output = Result<Self::Ready, Self::Error>>;
+///     type Ready = Result<Permit, Self::Error>;
+///     type ReadyFuture<'f> = impl Future<Output = Self::Ready>;
 ///
 ///     fn ready(&self) -> Self::ReadyFuture<'_> {
 ///         async move {
@@ -78,7 +78,7 @@ use super::service::Service;
 pub trait ReadyService<Req>: Service<Req> {
     type Ready;
 
-    type ReadyFuture<'f>: Future<Output = Result<Self::Ready, Self::Error>>
+    type ReadyFuture<'f>: Future<Output = Self::Ready>
     where
         Self: 'f;
 
@@ -92,7 +92,7 @@ macro_rules! impl_alloc {
             S: ReadyService<Req> + ?Sized,
         {
             type Ready = S::Ready;
-            type ReadyFuture<'f> = S::ReadyFuture<'f> where Self: 'f;
+            type ReadyFuture<'f> = S::ReadyFuture<'f> where S: 'f;
 
             #[inline]
             fn ready(&self) -> Self::ReadyFuture<'_> {
@@ -114,7 +114,7 @@ where
     type Ready = <S::Target as ReadyService<Req>>::Ready;
     type ReadyFuture<'f> = <S::Target as ReadyService<Req>>::ReadyFuture<'f>
     where
-        Self: 'f;
+        S: 'f;
 
     #[inline]
     fn ready(&self) -> Self::ReadyFuture<'_> {

test/tests/macro.rs

@@ -40,7 +40,7 @@ where
         Ok(TestMiddlewareService(service))
     }
 
-    async fn ready(&self) -> Result<S::Ready, Box<dyn std::error::Error>> {
+    async fn ready(&self) -> S::Ready {
         self.0.ready().await
     }
 

web/src/app/mod.rs

@@ -158,7 +158,7 @@ where
     S: for<'c1, 's1> ReadyService<&'c1 mut WebRequest<'s1, C>, Response = Res, Error = Err, Ready = R>,
 {
     type Ready = R;
-    type ReadyFuture<'f> = impl Future<Output = Result<Self::Ready, Self::Error>> where S: 'f;
+    type ReadyFuture<'f> = impl Future<Output = Self::Ready> where S: 'f;
 
     #[inline]
     fn ready(&self) -> Self::ReadyFuture<'_> {