Merge pull request #22 from WISVCH/graceful-shutdown

Add graceful shutdown to server

Cargo.toml

@@ -10,6 +10,6 @@ axum = "0.7"
 dotenv = "0.15"
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0.96"
-tokio = { version = "1", features = ["macros", "rt-multi-thread"] }
+tokio = { version = "1", features = ["macros", "rt-multi-thread", "signal"] }
 chrono = "0.4.31"
 wallet-pass = "0.4.0"

src/main.rs

@@ -1,10 +1,12 @@
+//! Web service to create Apple Wallet passes.
+
 use axum::{routing::get, Router};
 use tokio::net::TcpListener;
+use tokio::signal;
 
 mod models;
 mod passes;
 
-extern crate dotenv;
 use dotenv::dotenv;
 use passes::passes_handler;
 
@@ -24,6 +26,35 @@ async fn main() {
         .unwrap();
 
     axum::serve(listener, app.into_make_service())
+        .with_graceful_shutdown(shutdown_signal())
         .await
         .unwrap();
 }
+
+/// Graceful shutdown, useful for Docker containers.
+///
+/// Copied from the
+/// [axum graceful-shutdown example](https://github.com/tokio-rs/axum/blob/87b86a7066c320cb388ad4d27f32e7092b56b52f/examples/graceful-shutdown/src/main.rs).
+async fn shutdown_signal() {
+    let ctrl_c = async {
+        signal::ctrl_c()
+            .await
+            .expect("failed to install Ctrl+C handler");
+    };
+
+    #[cfg(unix)]
+    let terminate = async {
+        signal::unix::signal(signal::unix::SignalKind::terminate())
+            .expect("failed to install signal handler")
+            .recv()
+            .await;
+    };
+
+    #[cfg(not(unix))]
+    let terminate = std::future::pending::<()>();
+
+    tokio::select! {
+        _ = ctrl_c => {},
+        _ = terminate => {},
+    }
+}