Fix for failing build

client/src/session.rs

@@ -687,7 +687,7 @@ impl Session {
                     info!("Run session was terminated by a message {:?}", message);
                 }
                 else {
-                    debug!("Run session receiver is terminated, presumably by caller dropping oneshot");
+                    warn!("Run session was terminated, presumably by caller dropping oneshot sender. Don't do that unless you meant to.");
                 }
             }
         }

samples/web-client/Cargo.toml

@@ -11,6 +11,7 @@ serde = "1.0"
 serde_derive = "1.0"
 serde_json = "1.0"
 pico-args = "0.3"
+tokio = { version = "~1.8", features = ["full"] }
 
 [dependencies.opcua-client]
 path = "../../client"

samples/web-client/src/main.rs

@@ -8,7 +8,7 @@ extern crate serde_derive;
 
 use std::{
     str::FromStr,
-    sync::{mpsc, Arc, RwLock},
+    sync::{Arc, RwLock},
     time::{Duration, Instant},
 };
 
@@ -94,7 +94,7 @@ struct OPCUASession {
     /// The OPC UA session
     session: Option<Arc<RwLock<Session>>>,
     /// A sender that the session can use to terminate the corresponding OPC UA session
-    session_tx: Option<mpsc::Sender<SessionCommand>>,
+    session_tx: Option<tokio::sync::oneshot::Sender<SessionCommand>>,
 }
 
 impl Actor for OPCUASession {
@@ -243,11 +243,10 @@ impl OPCUASession {
                 session.disconnect();
             }
         }
-        if let Some(ref tx) = self.session_tx {
+        if let Some(mut tx) = self.session_tx.take() {
             let _ = tx.send(SessionCommand::Stop);
         }
         self.session = None;
-        self.session_tx = None;
     }
 
     fn lhs_operand(op: &str) -> Operand {