Reduced websocket latency

CHANGELOG.md

@@ -1,5 +1,8 @@
 # Changelog
 
+## Release 0.12.2
+- Reduced *WebSocket* latency.
+
 ## Release 0.12.1
 - *WebSocket* now can returns when send correctly a `SendStatus::MaxPacketSizeExceeded` instead of `ResourceNotFound` if the packet size is exceeded.
 - *UDP* has increases the packet size when send.

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "message-io"
-version = "0.12.1"
+version = "0.12.2"
 authors = ["lemunozm <[email protected]>"]
 edition = "2018"
 readme = "README.md"

src/adapters/ws.rs

@@ -114,10 +114,24 @@ impl Remote for RemoteResource {
                     match web_socket.read_message() {
                         Ok(message) => match message {
                             Message::Binary(data) => {
+                                // As an optimization.
+                                // Fast check to knwo if there is more data to avoid call
+                                // WebSocker::read_message() again.
+                                let mut should_wait = false;
+                                if let Err(err) = web_socket.get_ref().peek(&mut [0; 0]) {
+                                    if err.kind() == ErrorKind::WouldBlock {
+                                        should_wait = true;
+                                    }
+                                }
+
                                 // We can not call process_data while the socket is blocked.
                                 // The user could lock it again if sends from the callback.
                                 drop(state);
                                 process_data(&data);
+
+                                if should_wait {
+                                    break ReadStatus::WaitNextEvent
+                                }
                             }
                             Message::Close(_) => break ReadStatus::Disconnected,
                             _ => continue,