server: Add bounds and docs for associated types of Service trait (#266)

slowtec · Jul 21, 2024 · 528e797 · 528e797
1 parent dd1f676
commit 528e797
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Showing 5 changed files with 18 additions and 29 deletions.
diff --git a/src/lib.rs b/src/lib.rs
@@ -45,6 +45,8 @@ mod error;
 pub use self::error::{Error, ProtocolError};
 
 mod frame;
+#[cfg(feature = "server")]
+pub use self::frame::SlaveRequest;
 pub use self::frame::{
     Address, Exception, ExceptionResponse, FunctionCode, Quantity, Request, Response,
 };

diff --git a/src/server/rtu.rs b/src/server/rtu.rs
@@ -15,11 +15,9 @@ use crate::{
         rtu::{RequestAdu, ResponseAdu},
         ExceptionResponse, OptionalResponsePdu,
     },
-    server::service::Service,
-    Exception, Response,
 };
 
-use super::Terminated;
+use super::{Service, Terminated};
 
 #[derive(Debug)]
 pub struct Server {
@@ -45,8 +43,6 @@ impl Server {
     where
         S: Service + Send + Sync + 'static,
         S::Request: From<RequestAdu<'static>> + Send,
-        S::Response: Into<Option<Response>>,
-        S::Exception: Into<Exception>,
     {
         let framed = Framed::new(self.serial, ServerCodec::default());
         process(framed, service).await
@@ -60,8 +56,6 @@ impl Server {
     where
         S: Service + Send + Sync + 'static,
         S::Request: From<RequestAdu<'static>> + Send,
-        S::Response: Into<Option<Response>>,
-        S::Exception: Into<Exception>,
         X: Future<Output = ()> + Sync + Send + Unpin + 'static,
     {
         let framed = Framed::new(self.serial, ServerCodec::default());
@@ -82,8 +76,6 @@ async fn process<S>(mut framed: Framed<SerialStream, ServerCodec>, service: S) -
 where
     S: Service + Send + Sync + 'static,
     S::Request: From<RequestAdu<'static>> + Send,
-    S::Response: Into<Option<Response>>,
-    S::Exception: Into<Exception>,
 {
     loop {
         let Some(request) = framed.next().await.transpose()? else {

diff --git a/src/server/rtu_over_tcp.rs b/src/server/rtu_over_tcp.rs
@@ -20,11 +20,9 @@ use crate::{
         rtu::{RequestAdu, ResponseAdu},
         ExceptionResponse, OptionalResponsePdu,
     },
-    server::service::Service,
-    Exception, Response,
 };
 
-use super::Terminated;
+use super::{Service, Terminated};
 
 #[async_trait]
 pub trait BindSocket {
@@ -76,8 +74,6 @@ impl Server {
     where
         S: Service + Send + Sync + 'static,
         S::Request: From<RequestAdu<'static>> + Send,
-        S::Response: Into<Option<Response>>,
-        S::Exception: Into<Exception>,
         T: AsyncRead + AsyncWrite + Unpin + Send + 'static,
         OnConnected: Fn(TcpStream, SocketAddr) -> F,
         F: Future<Output = io::Result<Option<(S, T)>>>,
@@ -118,8 +114,6 @@ impl Server {
     where
         S: Service + Send + Sync + 'static,
         S::Request: From<RequestAdu<'static>> + Send,
-        S::Response: Into<Option<Response>>,
-        S::Exception: Into<Exception>,
         T: AsyncRead + AsyncWrite + Unpin + Send + 'static,
         X: Future<Output = ()> + Sync + Send + Unpin + 'static,
         OnConnected: Fn(TcpStream, SocketAddr) -> F,
@@ -143,8 +137,6 @@ async fn process<S, T>(mut framed: Framed<T, ServerCodec>, service: S) -> io::Re
 where
     S: Service + Send + Sync + 'static,
     S::Request: From<RequestAdu<'static>> + Send,
-    S::Response: Into<Option<Response>>,
-    S::Exception: Into<Exception>,
     T: AsyncRead + AsyncWrite + Unpin,
 {
     loop {

diff --git a/src/server/service.rs b/src/server/service.rs
@@ -6,13 +6,24 @@ use std::{future::Future, ops::Deref};
 /// A Modbus server service.
 pub trait Service {
     /// Requests handled by the service.
+    ///
+    /// Both [`tokio_modbus::Request`](crate::Request) and
+    /// [`tokio_modbus::SlaveRequest`](crate::SlaveRequest)
+    /// are possible choices.
     type Request;
 
     /// Responses sent by the service.
-    type Response;
+    ///
+    /// Both [`tokio_modbus::Response`](crate::Response) and
+    /// `Option<tokio_modbus::Response>` are possible choices.
+    /// The latter allows to selectively ignore requests
+    /// by not sending a response.
+    type Response: Into<Option<crate::Response>>;
 
     /// Exceptional responses sent by the service.
-    type Exception;
+    ///
+    /// Use [`tokio_modbus::Exception`](crate::Exception) as default.
+    type Exception: Into<crate::Exception>;
 
     /// The future response value.
     type Future: Future<Output = Result<Self::Response, Self::Exception>> + Send;

diff --git a/src/server/tcp.rs b/src/server/tcp.rs
@@ -20,11 +20,9 @@ use crate::{
         tcp::{RequestAdu, ResponseAdu},
         ExceptionResponse, OptionalResponsePdu,
     },
-    server::service::Service,
-    Exception, Response,
 };
 
-use super::Terminated;
+use super::{Service, Terminated};
 
 #[async_trait]
 pub trait BindSocket {
@@ -76,8 +74,6 @@ impl Server {
     where
         S: Service + Send + Sync + 'static,
         S::Request: From<RequestAdu<'static>> + Send,
-        S::Response: Into<Option<Response>>,
-        S::Exception: Into<Exception>,
         T: AsyncRead + AsyncWrite + Unpin + Send + 'static,
         OnConnected: Fn(TcpStream, SocketAddr) -> F,
         F: Future<Output = io::Result<Option<(S, T)>>>,
@@ -117,8 +113,6 @@ impl Server {
     where
         S: Service + Send + Sync + 'static,
         S::Request: From<RequestAdu<'static>> + Send,
-        S::Response: Into<Option<Response>>,
-        S::Exception: Into<Exception>,
         T: AsyncRead + AsyncWrite + Unpin + Send + 'static,
         X: Future<Output = ()> + Sync + Send + Unpin + 'static,
         OnConnected: Fn(TcpStream, SocketAddr) -> F,
@@ -142,8 +136,6 @@ async fn process<S, T>(mut framed: Framed<T, ServerCodec>, service: S) -> io::Re
 where
     S: Service + Send + Sync + 'static,
     S::Request: From<RequestAdu<'static>> + Send,
-    S::Response: Into<Option<Response>>,
-    S::Exception: Into<Exception>,
     T: AsyncRead + AsyncWrite + Unpin,
 {
     loop {