server: Remove unused trait bounds from Service::call() future resu…

…lt (#244)

* server: Remove unused trait bounds from `Service::call()` future result
* Add missing ?Sized

CHANGELOG.md

@@ -3,10 +3,15 @@
 
 # Changelog
 
+## v0.10.1 (Unreleased)
+
+- Server: Remove `Sync` and `Unpin` trait bounds from `Service::call()` future
+  result.
+
 ## v0.10.0 (2024-01-03)
 
 - Feature: Retrieve the `FunctionCode` of a `Request`/`Response`.
-- Feature: Added `rtu-over-tcp-server` for _RTU over TCP_ server skeleton.
+- Feature: Add `rtu-over-tcp-server` for _RTU over TCP_ server skeleton.
 
 ### Breaking Changes
 

src/server/service.rs

@@ -1,8 +1,7 @@
 // SPDX-FileCopyrightText: Copyright (c) 2017-2024 slowtec GmbH <[email protected]>
 // SPDX-License-Identifier: MIT OR Apache-2.0
 
-use std::future::Future;
-use std::ops::Deref;
+use std::{future::Future, ops::Deref};
 
 /// A Modbus server service.
 pub trait Service {
@@ -16,15 +15,15 @@ pub trait Service {
     type Error;
 
     /// The future response value.
-    type Future: Future<Output = Result<Self::Response, Self::Error>> + Send + Sync + Unpin;
+    type Future: Future<Output = Result<Self::Response, Self::Error>> + Send;
 
     /// Process the request and return the response asynchronously.
     fn call(&self, req: Self::Request) -> Self::Future;
 }
 
 impl<D> Service for D
 where
-    D: Deref,
+    D: Deref + ?Sized,
     D::Target: Service,
 {
     type Request = <D::Target as Service>::Request;