fix: runtime panic - Registering a blocking socket with tokio runtime is unsupported

thread 'tokio-runtime-worker' panicked at /home/josecelano/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/axum-server-0.8.0/src/server.rs:70:30:
Registering a blocking socket with the tokio runtime is unsupported. If you wish to do anyways, please add `--cfg tokio_allow_from_blocking_fd` to your RUSTFLAGS. See github.com/tokio-rs/tokio/issues/7172 for details.

Set std::net::TcpListener instances to non-blocking mode using set_nonblocking(true) before passing them to axum-server to avoid runtime panics when registering with tokio runtime.

This is required since axum-server 0.8.0 and tokio v1.44.0 which added debug assertions to prevent blocking sockets from being registered with the tokio runtime.

Author: josecelano

packages/axum-health-check-api-server/src/server.rs

@@ -101,6 +101,9 @@ pub fn start(
         .layer(SetRequestIdLayer::x_request_id(MakeRequestUuid));
 
     let socket = std::net::TcpListener::bind(bind_to).expect("Could not bind tcp_listener to address.");
+    socket
+        .set_nonblocking(true)
+        .expect("Failed to set socket to non-blocking mode");
     let address = socket.local_addr().expect("Could not get local_addr from tcp_listener.");
     let protocol = Protocol::HTTP; // The health check API only supports HTTP directly now. Use a reverse proxy for HTTPS.
     let service_binding = ServiceBinding::new(protocol.clone(), address).expect("Service binding creation failed");

packages/axum-http-tracker-server/src/server.rs

@@ -52,6 +52,9 @@ impl Launcher {
         rx_halt: Receiver<Halted>,
     ) -> BoxFuture<'static, ()> {
         let socket = std::net::TcpListener::bind(self.bind_to).expect("Could not bind tcp_listener to address.");
+        socket
+            .set_nonblocking(true)
+            .expect("Failed to set socket to non-blocking mode");
         let address = socket.local_addr().expect("Could not get local_addr from tcp_listener.");
 
         let handle = Handle::new();

packages/axum-rest-tracker-api-server/src/server.rs

@@ -247,6 +247,7 @@ impl Launcher {
         rx_halt: Receiver<Halted>,
     ) -> BoxFuture<'static, ()> {
         let socket = std::net::TcpListener::bind(self.bind_to).expect("Could not bind tcp_listener to address.");
+        socket.set_nonblocking(true).expect("Failed to set socket to non-blocking mode");
         let address = socket.local_addr().expect("Could not get local_addr from tcp_listener.");
 
         let router = router(http_api_container, access_tokens, address);