Lock writable stream before getting writer (#17)

* Lock writable stream before getting writer

* Make sure stream is ready to write

* cargo fmt

src/webtransport.rs

@@ -326,18 +326,24 @@ impl WebTransportTask {
             let result: Result<(), anyhow::Error> = async move {
                 let stream = transport.datagrams();
                 let stream: WritableStream = stream.writable();
+                if stream.locked() {
+                    return Err(anyhow::anyhow!("Stream is locked"));
+                }
                 let writer = stream.get_writer().map_err(|e| anyhow!("{:?}", e))?;
                 let data = Uint8Array::from(data.as_slice());
-                let _stream = JsFuture::from(writer.write_with_chunk(&data))
+                JsFuture::from(writer.ready())
                     .await
-                    .map_err(|e| anyhow::anyhow!("{:?}", e))?;
+                    .map_err(|e| anyhow!("{:?}", e))?;
+                JsFuture::from(writer.write_with_chunk(&data))
+                    .await
+                    .map_err(|e| anyhow!("{:?}", e))?;
                 writer.release_lock();
                 Ok(())
             }
             .await;
             if let Err(e) = result {
                 let e = e.to_string();
-                log!("error: {}", e);
+                log!("error: ", e);
                 transport_2.close();
             }
         });
@@ -353,6 +359,9 @@ impl WebTransportTask {
                     stream.map_err(|e| anyhow!("{:?}", e))?.unchecked_into();
                 let writer = stream.get_writer().map_err(|e| anyhow!("{:?}", e))?;
                 let data = Uint8Array::from(data.as_slice());
+                JsFuture::from(writer.ready())
+                    .await
+                    .map_err(|e| anyhow!("{:?}", e))?;
                 let _ = JsFuture::from(writer.write_with_chunk(&data))
                     .await
                     .map_err(|e| anyhow::anyhow!("{:?}", e))?;
@@ -420,6 +429,9 @@ impl WebTransportTask {
                     .get_writer()
                     .map_err(|e| anyhow!("{:?}", e))?;
 
+                JsFuture::from(writer.ready())
+                    .await
+                    .map_err(|e| anyhow!("{:?}", e))?;
                 let data = Uint8Array::from(data.as_slice());
                 let _ = JsFuture::from(writer.write_with_chunk(&data))
                     .await