add: graceful shutdown example

examples/graceful-shutdown/src/main.rs

@@ -0,0 +1,23 @@
+use salvo_core::prelude::*;
+use tokio::signal;
+
+#[tokio::main]
+async fn main() {
+    let acceptor = TcpListener::new("127.0.0.1:5800").bind().await;
+    let server = Server::new(acceptor);
+    let handle = server.handle();
+
+    // Listen Shutdown Signal
+    listen_shutdown_signal(handle);
+
+    server.serve(Router::new()).await;
+}
+
+async fn listen_shutdown_signal(handle: ServerHandle) {
+    // Wait Shutdown Signal
+    tokio::spawn(async move {
+        let _ = signal::ctrl_c().await;
+        // Graceful Shutdown Server
+        handle.stop_graceful(None);
+    })
+}