Feat: Echo TCP server

- Each message sent by a TCP client will be bounced back to them.
- Support multiple clients

src/main.rs

@@ -0,0 +1,43 @@
+use tokio::{
+    io::{AsyncBufReadExt, AsyncWriteExt, BufReader},
+    net::TcpListener,
+};
+
+#[tokio::main]
+async fn main() {
+    // Set up a TCP listenner to listen for incoming tcp requests
+    let listener = TcpListener::bind("127.0.0.1:8080").await.unwrap();
+
+    // First loop accept all the tcp client requests
+    loop {
+        // accept the requests
+        let (mut socket, _addr) = listener.accept().await.unwrap();
+
+        tokio::spawn(async move {
+            // Splitting the TCP socket into read/write halves
+            let (reader, mut writer) = socket.split();
+
+            let mut buffer_reader = BufReader::new(reader);
+
+            let mut line: String = String::new();
+
+            // second loop keeps receving input from that one client going
+            loop {
+                // number of bytes read. We will truncate the buffer
+                let bytes_read = buffer_reader.read_line(&mut line).await.unwrap();
+
+                // If we received no bytes then the tcp socket must have closed
+                if bytes_read == 0 {
+                    break;
+                }
+
+                // Does not write to every single tcp sockets that are connected
+                // It only writes every single bytes in the input buffer
+                writer.write_all(line.as_bytes()).await.unwrap();
+
+                // clear the input buffer
+                line.clear();
+            }
+        });
+    }
+}