Merge pull request #246 from jpoles1/master

Adding basic code comments to async-client example

Author: vi

examples/async-client.rs

@@ -13,56 +13,70 @@ use websocket::{ClientBuilder, OwnedMessage};
 
 const CONNECTION: &'static str = "ws://127.0.0.1:2794";
 
+// Async websocket chat client
 fn main() {
 	println!("Connecting to {}", CONNECTION);
+
+	// Construct new Tokio runtime environment
 	let mut runtime = tokio::runtime::current_thread::Builder::new()
 		.build()
 		.unwrap();
 
-	// standard in isn't supported in mio yet, so we use a thread
-	// see https://github.com/carllerche/mio/issues/321
 	let (usr_msg, stdin_ch) = mpsc::channel(0);
+
+	// Spawn new thread to read user input
+	// stdin isn't supported in mio yet, so we use a thread
+	// see https://github.com/carllerche/mio/issues/321
 	thread::spawn(|| {
 		let mut input = String::new();
 		let mut stdin_sink = usr_msg.wait();
 		loop {
+			// Read user input from stdin
 			input.clear();
 			stdin().read_line(&mut input).unwrap();
+			
+			// Trim whitespace and match input to known chat commands
+			// If input is unknown, send trimmed input as a chat message 
 			let trimmed = input.trim();
-
 			let (close, msg) = match trimmed {
 				"/close" => (true, OwnedMessage::Close(None)),
 				"/ping" => (false, OwnedMessage::Ping(b"PING".to_vec())),
 				_ => (false, OwnedMessage::Text(trimmed.to_string())),
 			};
-
+			// Send message to websocket server
 			stdin_sink
 				.send(msg)
 				.expect("Sending message across stdin channel.");
-
+			// If user entered the "/close" command, break the loop
 			if close {
 				break;
 			}
 		}
 	});
 
+	// Construct a new connection to the websocket server 
 	let runner = ClientBuilder::new(CONNECTION)
 		.unwrap()
 		.add_protocol("rust-websocket")
 		.async_connect_insecure()
 		.and_then(|(duplex, _)| {
 			let (sink, stream) = duplex.split();
 			stream
+				// Iterate over message as they arrive in stream
 				.filter_map(|message| {
 					println!("Received Message: {:?}", message);
+					// Respond to close or ping commands from the server
 					match message {
 						OwnedMessage::Close(e) => Some(OwnedMessage::Close(e)),
 						OwnedMessage::Ping(d) => Some(OwnedMessage::Pong(d)),
 						_ => None,
 					}
 				})
+				// Takes in messages from both sinks
 				.select(stdin_ch.map_err(|_| WebSocketError::NoDataAvailable))
+				// Return a future that completes once all incoming data from the above streams has been processed into the sink
 				.forward(sink)
 		});
+	// Start our websocket client runner in the Tokio environment
 	runtime.block_on(runner).unwrap();
 }