Modify Server::Service:call signature to include request's unit ID

examples/rtu-server.rs

@@ -14,7 +14,7 @@ pub async fn main() -> Result<(), Box<dyn std::error::Error>> {
         type Error = std::io::Error;
         type Future = future::Ready<Result<Self::Response, Self::Error>>;
 
-        fn call(&self, req: Self::Request) -> Self::Future {
+        fn call(&self, _: Slave, req: Self::Request) -> Self::Future {
             match req {
                 Request::ReadInputRegisters(_addr, cnt) => {
                     let mut registers = vec![0; cnt as usize];

examples/tcp-server.rs

@@ -14,7 +14,7 @@ pub async fn main() -> Result<(), Box<dyn std::error::Error>> {
         type Error = std::io::Error;
         type Future = future::Ready<Result<Self::Response, Self::Error>>;
 
-        fn call(&self, req: Self::Request) -> Self::Future {
+        fn call(&self, _: Slave, req: Self::Request) -> Self::Future {
             match req {
                 Request::ReadInputRegisters(_addr, cnt) => {
                     let mut registers = vec![0; cnt as usize];

src/server/rtu.rs

@@ -87,7 +87,10 @@ where
         }?;
 
         let hdr = request.hdr;
-        let response = service.call(request.pdu.0).await.map_err(Into::into)?;
+        let response = service
+            .call(request.hdr.slave_id.into(), request.pdu.0)
+            .await
+            .map_err(Into::into)?;
         framed
             .send(rtu::ResponseAdu {
                 hdr,

src/server/service.rs

@@ -1,3 +1,4 @@
+use crate::slave::Slave;
 use std::{future::Future, io, rc::Rc, sync::Arc};
 
 /// A Modbus server service.
@@ -15,7 +16,7 @@ pub trait Service {
     type Future: Future<Output = Result<Self::Response, Self::Error>> + Send + Sync + Unpin;
 
     /// Process the request and return the response asynchronously.
-    fn call(&self, req: Self::Request) -> Self::Future;
+    fn call(&self, slave: Slave, req: Self::Request) -> Self::Future;
 }
 
 /// Creates new `Service` values.
@@ -79,8 +80,8 @@ impl<S: Service + ?Sized + 'static> Service for Box<S> {
     type Error = S::Error;
     type Future = S::Future;
 
-    fn call(&self, request: S::Request) -> Self::Future {
-        (**self).call(request)
+    fn call(&self, slave: Slave, request: S::Request) -> Self::Future {
+        (**self).call(slave, request)
     }
 }
 
@@ -90,8 +91,8 @@ impl<S: Service + ?Sized + 'static> Service for Rc<S> {
     type Error = S::Error;
     type Future = S::Future;
 
-    fn call(&self, request: S::Request) -> Self::Future {
-        (**self).call(request)
+    fn call(&self, slave: Slave, request: S::Request) -> Self::Future {
+        (**self).call(slave, request)
     }
 }
 
@@ -101,7 +102,7 @@ impl<S: Service + ?Sized + 'static> Service for Arc<S> {
     type Error = S::Error;
     type Future = S::Future;
 
-    fn call(&self, request: S::Request) -> Self::Future {
-        (**self).call(request)
+    fn call(&self, slave: Slave, request: S::Request) -> Self::Future {
+        (**self).call(slave, request)
     }
 }

src/server/tcp.rs

@@ -145,7 +145,10 @@ where
 
         let request = request.unwrap()?;
         let hdr = request.hdr;
-        let response = service.call(request.pdu.0).await.map_err(Into::into)?;
+        let response = service
+            .call(request.hdr.unit_id.into(), request.pdu.0)
+            .await
+            .map_err(Into::into)?;
 
         framed
             .send(tcp::ResponseAdu {
@@ -187,6 +190,7 @@ fn configure_tcp(_workers: usize, _tcp: &Socket) -> io::Result<()> {
 mod tests {
     use super::*;
     use crate::server::Service;
+    use crate::slave::Slave;
 
     use futures::future;
 
@@ -203,7 +207,7 @@ mod tests {
             type Error = Error;
             type Future = future::Ready<Result<Self::Response, Self::Error>>;
 
-            fn call(&self, _: Self::Request) -> Self::Future {
+            fn call(&self, _: Slave, _: Self::Request) -> Self::Future {
                 future::ready(Ok(self.response.clone()))
             }
         }
@@ -212,8 +216,9 @@ mod tests {
             response: Response::ReadInputRegisters(vec![0x33]),
         };
 
+        let slave = Slave(1);
         let pdu = Request::ReadInputRegisters(0, 1);
-        let rsp_adu = service.call(pdu).await.unwrap();
+        let rsp_adu = service.call(slave, pdu).await.unwrap();
 
         assert_eq!(rsp_adu, service.response);
     }