add channel to get send result

Currently the send() method of stream implemented by send the value to
an unbounded channel, so even the connection is closed for a long time,
the send function still return succeed. This commit adds a channel to the
message so that we can wait until the message is truely written to the
connection.

Signed-off-by: Abel Feng <[email protected]>

src/asynchronous/client.rs

@@ -27,6 +27,8 @@ use crate::r#async::stream::{
 };
 use crate::r#async::utils;
 
+use super::stream::SendingMessage;
+
 /// A ttrpc Client (async).
 #[derive(Clone)]
 pub struct Client {
@@ -78,7 +80,7 @@ impl Client {
         self.streams.lock().unwrap().insert(stream_id, tx);
 
         self.req_tx
-            .send(msg)
+            .send(SendingMessage::new(msg))
             .await
             .map_err(|e| Error::Others(format!("Send packet to sender error {e:?}")))?;
 
@@ -139,7 +141,7 @@ impl Client {
         // TODO: check return
         self.streams.lock().unwrap().insert(stream_id, tx);
         self.req_tx
-            .send(msg)
+            .send(SendingMessage::new(msg))
             .await
             .map_err(|e| Error::Others(format!("Send packet to sender error {e:?}")))?;
 
@@ -204,7 +206,7 @@ struct ClientWriter {
 
 #[async_trait]
 impl WriterDelegate for ClientWriter {
-    async fn recv(&mut self) -> Option<GenMessage> {
+    async fn recv(&mut self) -> Option<SendingMessage> {
         self.rx.recv().await
     }
 

src/asynchronous/connection.rs

@@ -16,6 +16,8 @@ use tokio::{
 use crate::error::Error;
 use crate::proto::{GenMessage, GenMessageError, MessageHeader};
 
+use super::stream::SendingMessage;
+
 pub trait Builder {
     type Reader;
     type Writer;
@@ -25,7 +27,7 @@ pub trait Builder {
 
 #[async_trait]
 pub trait WriterDelegate {
-    async fn recv(&mut self) -> Option<GenMessage>;
+    async fn recv(&mut self) -> Option<SendingMessage>;
     async fn disconnect(&self, msg: &GenMessage, e: Error);
     async fn exit(&self);
 }
@@ -58,12 +60,14 @@ where
         let (reader_delegate, mut writer_delegate) = builder.build();
 
         let writer_task = tokio::spawn(async move {
-            while let Some(msg) = writer_delegate.recv().await {
-                trace!("write message: {:?}", msg);
-                if let Err(e) = msg.write_to(&mut writer).await {
+            while let Some(mut sending_msg) = writer_delegate.recv().await {
+                trace!("write message: {:?}", sending_msg.msg);
+                if let Err(e) = sending_msg.msg.write_to(&mut writer).await {
                     error!("write_message got error: {:?}", e);
-                    writer_delegate.disconnect(&msg, e).await;
+                    sending_msg.send_result(Err(e.clone()));
+                    writer_delegate.disconnect(&sending_msg.msg, e).await;
                 }
+                sending_msg.send_result(Ok(()));
             }
             writer_delegate.exit().await;
             trace!("Writer task exit.");

src/asynchronous/server.rs

@@ -31,7 +31,7 @@ use tokio::{
 #[cfg(any(target_os = "linux", target_os = "android"))]
 use tokio_vsock::VsockListener;
 
-use crate::asynchronous::unix_incoming::UnixIncoming;
+use crate::asynchronous::{stream::SendingMessage, unix_incoming::UnixIncoming};
 use crate::common::{self, Domain};
 use crate::context;
 use crate::error::{get_status, Error, Result};
@@ -339,7 +339,7 @@ struct ServerWriter {
 
 #[async_trait]
 impl WriterDelegate for ServerWriter {
-    async fn recv(&mut self) -> Option<GenMessage> {
+    async fn recv(&mut self) -> Option<SendingMessage> {
         self.rx.recv().await
     }
     async fn disconnect(&self, _msg: &GenMessage, _: Error) {}
@@ -462,7 +462,7 @@ impl HandlerContext {
                         };
 
                         self.tx
-                            .send(msg)
+                            .send(SendingMessage::new(msg))
                             .await
                             .map_err(err_to_others_err!(e, "Send packet to sender error "))
                             .ok();
@@ -652,7 +652,7 @@ impl HandlerContext {
             header: MessageHeader::new_response(stream_id, payload.len() as u32),
             payload,
         };
-        tx.send(msg)
+        tx.send(SendingMessage::new(msg))
             .await
             .map_err(err_to_others_err!(e, "Send packet to sender error "))
     }

src/asynchronous/stream.rs

@@ -17,12 +17,42 @@ use crate::proto::{
     MESSAGE_TYPE_DATA, MESSAGE_TYPE_RESPONSE,
 };
 
-pub type MessageSender = mpsc::Sender<GenMessage>;
-pub type MessageReceiver = mpsc::Receiver<GenMessage>;
+pub type MessageSender = mpsc::Sender<SendingMessage>;
+pub type MessageReceiver = mpsc::Receiver<SendingMessage>;
 
 pub type ResultSender = mpsc::Sender<Result<GenMessage>>;
 pub type ResultReceiver = mpsc::Receiver<Result<GenMessage>>;
 
+#[derive(Debug)]
+pub struct SendingMessage {
+    pub msg: GenMessage,
+    pub result_chan: Option<tokio::sync::oneshot::Sender<Result<()>>>,
+}
+
+impl SendingMessage {
+    pub fn new(msg: GenMessage) -> Self {
+        Self {
+            msg,
+            result_chan: None,
+        }
+    }
+    pub fn new_with_result(
+        msg: GenMessage,
+        result_chan: tokio::sync::oneshot::Sender<Result<()>>,
+    ) -> Self {
+        Self {
+            msg,
+            result_chan: Some(result_chan),
+        }
+    }
+
+    pub fn send_result(&mut self, result: Result<()>) {
+        if let Some(result_ch) = self.result_chan.take() {
+            result_ch.send(result).unwrap_or_default();
+        }
+    }
+}
+
 #[derive(Debug)]
 pub struct ClientStream<Q, P> {
     tx: CSSender<Q>,
@@ -317,9 +347,13 @@ async fn _recv(rx: &mut ResultReceiver) -> Result<GenMessage> {
 }
 
 async fn _send(tx: &MessageSender, msg: GenMessage) -> Result<()> {
-    tx.send(msg)
+    let (res_tx, res_rx) = tokio::sync::oneshot::channel();
+    tx.send(SendingMessage::new_with_result(msg, res_tx))
+        .await
+        .map_err(|e| Error::Others(format!("Send data packet to sender error {:?}", e)))?;
+    res_rx
         .await
-        .map_err(|e| Error::Others(format!("Send data packet to sender error {e:?}")))
+        .map_err(|e| Error::Others(format!("Failed to wait send result {:?}", e)))?
 }
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]