Added XmppCodec usage example

tokio-xmpp/examples/echo_server.rs

@@ -0,0 +1,37 @@
+use futures::{SinkExt, StreamExt};
+use tokio::{self, io, net::TcpSocket};
+use tokio_util::codec::Framed;
+
+use tokio_xmpp::XMPPCodec;
+
+#[tokio::main]
+async fn main() -> Result<(), io::Error> {
+    // TCP socket
+    let address = "127.0.0.1:5222".parse().unwrap();
+    let socket = TcpSocket::new_v4()?;
+    socket.bind(address)?;
+
+    let listener = socket.listen(1024)?;
+
+    // Main loop, accepts incoming connections
+    loop {
+        let (stream, _addr) = listener.accept().await?;
+
+        // Use the `XMPPCodec` to encode and decode frames
+        let mut framed = Framed::new(stream, XMPPCodec::new());
+
+        tokio::spawn(async move {
+            while let Some(packet) = framed.next().await {
+                match packet {
+                    Ok(packet) => {
+                        println!("Received packet: {:?}", packet);
+                        framed.send(packet).await.unwrap();
+                    }
+                    Err(e) => {
+                        eprintln!("Error: {:?}", e);
+                    }
+                }
+            }
+        });
+    }
+}