feat: implement asynchronous channel support with tokio integration

src/asynchronous/tokio.rs

@@ -0,0 +1,113 @@
+use std::sync::Arc;
+
+use arc_swap::ArcSwap;
+use async_trait::async_trait;
+use tokio::sync::{Mutex, mpsc};
+
+use crate::asynchronous::traits::{
+    AsyncChannelReceiver, AsyncChannelSender, AsyncChannelType, ChannelError,
+};
+use crate::types;
+
+type TokioSucker<T> =
+    crate::AsyncSucker<T, TokioSender<types::Request>, TokioReceiver<types::Response<T>>>;
+type TokioSourcer<T> =
+    crate::AsyncSourcer<T, TokioReceiver<types::Request>, TokioSender<types::Response<T>>>;
+
+pub struct TokioSender<T>(mpsc::UnboundedSender<T>);
+pub struct TokioReceiver<T>(Mutex<mpsc::UnboundedReceiver<T>>);
+
+#[async_trait]
+impl<T: Send + 'static> AsyncChannelSender<T> for TokioSender<T> {
+    async fn send(&self, msg: T) -> Result<(), ChannelError> {
+        self.0
+            .send(msg)
+            .map_err(|_| ChannelError::ProducerDisconnected)
+    }
+}
+
+#[async_trait]
+impl<T: Send + 'static> AsyncChannelReceiver<T> for TokioReceiver<T> {
+    async fn recv(&self) -> Result<T, ChannelError> {
+        let mut receiver = self.0.lock().await;
+        receiver
+            .recv()
+            .await
+            .ok_or(ChannelError::ProducerDisconnected)
+    }
+}
+
+pub struct TokioChannel;
+
+impl AsyncChannelType for TokioChannel {
+    type Sender<T: Send + 'static> = TokioSender<T>;
+    type Receiver<T: Send + 'static> = TokioReceiver<T>;
+
+    fn create_request_channel() -> (Self::Sender<types::Request>, Self::Receiver<types::Request>) {
+        let (tx, rx) = mpsc::unbounded_channel();
+        (TokioSender(tx), TokioReceiver(Mutex::new(rx)))
+    }
+
+    fn create_response_channel<T: Send + 'static>() -> (
+        Self::Sender<types::Response<T>>,
+        Self::Receiver<types::Response<T>>,
+    ) {
+        let (tx, rx) = mpsc::unbounded_channel();
+        (TokioSender(tx), TokioReceiver(Mutex::new(rx)))
+    }
+}
+
+pub struct TokioSuck<T> {
+    _phantom: std::marker::PhantomData<T>,
+}
+
+impl<T> TokioSuck<T> {
+    pub fn pair() -> (TokioSucker<T>, TokioSourcer<T>)
+    where
+        T: Clone + Send + 'static,
+    {
+        let (request_tx, request_rx) = TokioChannel::create_request_channel();
+        let (response_tx, response_rx) = TokioChannel::create_response_channel::<T>();
+        let state = ArcSwap::new(Arc::new(crate::types::ValueSource::None));
+
+        let sucker = crate::AsyncSucker::new(request_tx, response_rx);
+        let sourcer = crate::AsyncSourcer::new(request_rx, response_tx, state);
+
+        (sucker, sourcer)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::Error;
+
+    #[tokio::test]
+    async fn test_pre_computed_value() {
+        let (sucker, sourcer) = TokioSuck::<i32>::pair();
+
+        let producer = tokio::spawn(async move {
+            sourcer.set_static(42).unwrap();
+            sourcer.run().await.unwrap();
+        });
+
+        let value = sucker.get().await.unwrap();
+        assert_eq!(value, 42);
+        sucker.close().await.unwrap();
+        producer.await.unwrap();
+    }
+
+    #[tokio::test]
+    async fn test_no_source_error() {
+        let (sucker, sourcer) = TokioSuck::<i32>::pair();
+
+        let producer = tokio::spawn(async move {
+            sourcer.run().await.unwrap();
+        });
+
+        let result = sucker.get().await;
+        assert!(matches!(result, Err(Error::NoSource)));
+        sucker.close().await.unwrap();
+        producer.await.unwrap();
+    }
+}