simpletransaction works

1 files changed, 58 insertions, 0 deletions

diff --git a/src/transaction/mod.rs b/src/transaction/mod.rs
new file mode 100644
index 0000000..2953cb7
--- /dev/null
+++ b/src/transaction/mod.rs
@@ -0,0 +1,58 @@
+use crate::{
+    encoding::{headers::CSeq, request::Request, response::Response},
+    transport::Transport,
+};
+use anyhow::{anyhow, Result};
+use std::{
+    collections::HashMap,
+    sync::atomic::{AtomicU32, Ordering},
+};
+use tokio::sync::{
+    mpsc::{self, channel},
+    RwLock,
+};
+
+pub struct TransactionUser<T> {
+    transport: T,
+    sequence: AtomicU32,
+    pending_requests: RwLock<HashMap<CSeq, mpsc::Sender<Response>>>,
+}
+
+impl<T: Transport> TransactionUser<T> {
+    pub fn new(transport: T) -> Self {
+        Self {
+            sequence: 0.into(),
+            pending_requests: Default::default(),
+            transport,
+        }
+    }
+
+    pub async fn process_responses(&self) -> Result<()> {
+        let resp = self.transport.recv().await?;
+        let cseq = resp
+            .headers
+            .get()
+            .ok_or(anyhow!("response cseq missing"))??;
+        self.pending_requests
+            .write()
+            .await
+            .get_mut(&cseq)
+            .ok_or(anyhow!("message was not requested"))?
+            .send(resp)
+            .await?;
+        Ok(())
+    }
+
+    pub async fn transact(&self, mut request: Request) -> Result<mpsc::Receiver<Response>> {
+        let seq = self.sequence.fetch_add(1, Ordering::Relaxed);
+        let cseq = CSeq(seq, request.method);
+        request.headers.insert(cseq);
+
+        let (tx, rx) = channel(4);
+
+        self.transport.send(request).await?;
+        self.pending_requests.write().await.insert(cseq, tx);
+
+        Ok(rx)
+    }
+}