cli: add more details to the status command

cli/src/commands/tunnels.rs

@@ -35,7 +35,7 @@ use crate::{
 		code_server::CodeServerArgs,
 		create_service_manager,
 		dev_tunnels::{self, DevTunnels},
-		local_forwarding, legal,
+		legal, local_forwarding,
 		paths::get_all_servers,
 		protocol, serve_stream,
 		shutdown_signal::ShutdownRequest,
@@ -326,12 +326,12 @@ pub async fn kill(ctx: CommandContext) -> Result<i32, AnyError> {
 
 #[derive(Serialize)]
 pub struct StatusOutput {
-	pub tunnel: Option<protocol::singleton::TunnelState>,
+	pub tunnel: Option<protocol::singleton::StatusWithTunnelName>,
 	pub service_installed: bool,
 }
 
 pub async fn status(ctx: CommandContext) -> Result<i32, AnyError> {
-	let tunnel_status = do_single_rpc_call::<_, protocol::singleton::Status>(
+	let tunnel = do_single_rpc_call::<_, protocol::singleton::StatusWithTunnelName>(
 		&ctx.paths.tunnel_lockfile(),
 		ctx.log.clone(),
 		protocol::singleton::METHOD_STATUS,
@@ -347,8 +347,8 @@ pub async fn status(ctx: CommandContext) -> Result<i32, AnyError> {
 	ctx.log.result(
 		serde_json::to_string(&StatusOutput {
 			service_installed,
-			tunnel: match tunnel_status {
-				Ok(s) => Some(s.tunnel),
+			tunnel: match tunnel {
+				Ok(s) => Some(s),
 				Err(CodeError::NoRunningTunnel) => None,
 				Err(e) => return Err(e.into()),
 			},

cli/src/tunnels/dev_tunnels.rs

@@ -31,7 +31,7 @@ use tunnels::management::{
 	NO_REQUEST_OPTIONS,
 };
 
-use super::protocol::PortPrivacy;
+use super::protocol::{self, PortPrivacy};
 use super::wsl_detect::is_wsl_installed;
 
 static TUNNEL_COUNT_LIMIT_NAME: &str = "TunnelsPerUserPerLocation";
@@ -203,6 +203,11 @@ impl ActiveTunnel {
 		self.get_port_format()
 			.map(|f| f.replace(PORT_TOKEN, &port.to_string()))
 	}
+
+	/// Gets an object to read the current tunnel status.
+	pub fn status(&self) -> StatusLock {
+		self.manager.get_status()
+	}
 }
 
 const VSCODE_CLI_TUNNEL_TAG: &str = "vscode-server-launcher";
@@ -843,10 +848,36 @@ impl DevTunnels {
 	}
 }
 
+#[derive(Clone, Default)]
+pub struct StatusLock(Arc<std::sync::Mutex<protocol::singleton::Status>>);
+
+impl StatusLock {
+	fn succeed(&self) {
+		let mut status = self.0.lock().unwrap();
+		status.tunnel = protocol::singleton::TunnelState::Connected;
+		status.last_connected_at = Some(chrono::Utc::now());
+	}
+
+	fn fail(&self, reason: String) {
+		let mut status = self.0.lock().unwrap();
+		if let protocol::singleton::TunnelState::Connected = status.tunnel {
+			status.last_disconnected_at = Some(chrono::Utc::now());
+			status.tunnel = protocol::singleton::TunnelState::Disconnected;
+		}
+		status.last_fail_reason = Some(reason);
+	}
+
+	pub fn read(&self) -> protocol::singleton::Status {
+		let status = self.0.lock().unwrap();
+		status.clone()
+	}
+}
+
 struct ActiveTunnelManager {
 	close_tx: Option<mpsc::Sender<()>>,
 	endpoint_rx: watch::Receiver<Option<Result<TunnelRelayTunnelEndpoint, WrappedError>>>,
 	relay: Arc<tokio::sync::Mutex<RelayTunnelHost>>,
+	status: StatusLock,
 }
 
 impl ActiveTunnelManager {
@@ -862,13 +893,17 @@ impl ActiveTunnelManager {
 		let relay = Arc::new(tokio::sync::Mutex::new(RelayTunnelHost::new(locator, mgmt)));
 		let relay_spawned = relay.clone();
 
+		let status = StatusLock::default();
+
+		let status_spawned = status.clone();
 		tokio::spawn(async move {
 			ActiveTunnelManager::spawn_tunnel(
 				log,
 				relay_spawned,
 				close_rx,
 				endpoint_tx,
 				access_token,
+				status_spawned,
 			)
 			.await;
 		});
@@ -877,9 +912,15 @@ impl ActiveTunnelManager {
 			endpoint_rx,
 			relay,
 			close_tx: Some(close_tx),
+			status,
 		}
 	}
 
+	/// Gets a copy of the current tunnel status information
+	pub fn get_status(&self) -> StatusLock {
+		self.status.clone()
+	}
+
 	/// Adds a port for TCP/IP forwarding.
 	#[allow(dead_code)] // todo: port forwarding
 	pub async fn add_port_tcp(
@@ -967,12 +1008,15 @@ impl ActiveTunnelManager {
 		mut close_rx: mpsc::Receiver<()>,
 		endpoint_tx: watch::Sender<Option<Result<TunnelRelayTunnelEndpoint, WrappedError>>>,
 		access_token_provider: impl AccessTokenProvider + 'static,
+		status: StatusLock,
 	) {
 		let mut backoff = Backoff::new(Duration::from_secs(5), Duration::from_secs(120));
 
 		macro_rules! fail {
 			($e: expr, $msg: expr) => {
-				warning!(log, "{}: {}", $msg, $e);
+				let fmt = format!("{}: {}", $msg, $e);
+				warning!(log, &fmt);
+				status.fail(fmt);
 				endpoint_tx.send(Some(Err($e))).ok();
 				backoff.delay().await;
 			};
@@ -1008,6 +1052,7 @@ impl ActiveTunnelManager {
 			};
 
 			backoff.reset();
+			status.succeed();
 			endpoint_tx.send(Some(Ok(handle.endpoint().clone()))).ok();
 
 			tokio::select! {

cli/src/tunnels/protocol.rs

@@ -249,6 +249,7 @@ pub mod forward_singleton {
 
 pub mod singleton {
 	use crate::log;
+	use chrono::{DateTime, Utc};
 	use serde::{Deserialize, Serialize};
 
 	pub const METHOD_RESTART: &str = "restart";
@@ -271,17 +272,41 @@ pub mod singleton {
 		pub message: String,
 	}
 
-	#[derive(Serialize, Deserialize)]
+	#[derive(Serialize, Deserialize, Clone, Default)]
+	pub struct StatusWithTunnelName {
+		pub name: Option<String>,
+		#[serde(flatten)]
+		pub status: Status,
+	}
+
+	#[derive(Serialize, Deserialize, Clone)]
 	pub struct Status {
+		pub started_at: DateTime<Utc>,
 		pub tunnel: TunnelState,
+		pub last_connected_at: Option<DateTime<Utc>>,
+		pub last_disconnected_at: Option<DateTime<Utc>>,
+		pub last_fail_reason: Option<String>,
+	}
+
+	impl Default for Status {
+		fn default() -> Self {
+			Self {
+				started_at: Utc::now(),
+				tunnel: TunnelState::Disconnected,
+				last_connected_at: None,
+				last_disconnected_at: None,
+				last_fail_reason: None,
+			}
+		}
 	}
 
 	#[derive(Deserialize, Serialize, Debug)]
 	pub struct LogReplayFinished {}
 
-	#[derive(Deserialize, Serialize, Debug)]
+	#[derive(Deserialize, Serialize, Debug, Default, Clone)]
 	pub enum TunnelState {
+		#[default]
 		Disconnected,
-		Connected { name: String },
+		Connected,
 	}
 }

cli/src/tunnels/singleton_client.rs

@@ -114,16 +114,18 @@ pub async fn start_singleton_client(args: SingletonClientArgs) -> bool {
 				CONTROL_INSTRUCTIONS_COMMON
 			});
 
-			let res = c.caller.call::<_, _, protocol::singleton::Status>(
-				protocol::singleton::METHOD_STATUS,
-				protocol::EmptyObject {},
-			);
+			let res = c
+				.caller
+				.call::<_, _, protocol::singleton::StatusWithTunnelName>(
+					protocol::singleton::METHOD_STATUS,
+					protocol::EmptyObject {},
+				);
 
 			// we want to ensure the "listening" string always gets printed for
 			// consumers (i.e. VS Code). Ask for it. If the tunnel is not currently
 			// connected though, it will be soon, and that'll be in the log replays.
 			if let Ok(Ok(s)) = res.await {
-				if let protocol::singleton::TunnelState::Connected { name } = s.tunnel {
+				if let Some(name) = s.name {
 					print_listening(&c.log, &name);
 				}
 			}

cli/src/tunnels/singleton_server.rs

@@ -11,7 +11,7 @@ use std::{
 use super::{
 	code_server::CodeServerArgs,
 	control_server::ServerTermination,
-	dev_tunnels::ActiveTunnel,
+	dev_tunnels::{ActiveTunnel, StatusLock},
 	protocol,
 	shutdown_signal::{ShutdownRequest, ShutdownSignal},
 };
@@ -48,18 +48,28 @@ pub struct SingletonServerArgs<'a> {
 	pub log_broadcast: &'a BroadcastLogSink,
 }
 
+struct StatusInfo {
+	name: String,
+	lock: StatusLock,
+}
+
 #[derive(Clone)]
 struct SingletonServerContext {
 	log: log::Logger,
 	shutdown_tx: broadcast::Sender<ShutdownSignal>,
 	broadcast_tx: broadcast::Sender<Vec<u8>>,
-	current_name: Arc<Mutex<Option<String>>>,
+	// ugly: a lock in a lock. current_status needs to be provided only
+	// after we set up the tunnel, however the tunnel is created after the
+	// singleton server starts to avoid a gap in singleton availability.
+	// However, this should be safe, as the lock is only used for immediate
+	// data reads (in the `status` method).
+	current_status: Arc<Mutex<Option<StatusInfo>>>,
 }
 
 pub struct RpcServer {
 	fut: JoinHandle<Result<(), CodeError>>,
 	shutdown_broadcast: broadcast::Sender<ShutdownSignal>,
-	current_name: Arc<Mutex<Option<String>>>,
+	current_status: Arc<Mutex<Option<StatusInfo>>>,
 }
 
 pub fn make_singleton_server(
@@ -71,12 +81,12 @@ pub fn make_singleton_server(
 	let (shutdown_broadcast, _) = broadcast::channel(4);
 	let rpc = new_json_rpc();
 
-	let current_name = Arc::new(Mutex::new(None));
+	let current_status = Arc::new(Mutex::default());
 	let mut rpc = rpc.methods(SingletonServerContext {
 		log: log.clone(),
 		shutdown_tx: shutdown_broadcast.clone(),
 		broadcast_tx: log_broadcast.get_brocaster(),
-		current_name: current_name.clone(),
+		current_status: current_status.clone(),
 	});
 
 	rpc.register_sync(
@@ -91,12 +101,15 @@ pub fn make_singleton_server(
 	rpc.register_sync(
 		protocol::singleton::METHOD_STATUS,
 		|_: protocol::EmptyObject, c| {
-			Ok(protocol::singleton::Status {
-				tunnel: match c.current_name.lock().unwrap().clone() {
-					Some(name) => protocol::singleton::TunnelState::Connected { name },
-					None => protocol::singleton::TunnelState::Disconnected,
-				},
-			})
+			Ok(c.current_status
+				.lock()
+				.unwrap()
+				.as_ref()
+				.map(|s| protocol::singleton::StatusWithTunnelName {
+					name: Some(s.name.clone()),
+					status: s.lock.read(),
+				})
+				.unwrap_or_default())
 		},
 	);
 
@@ -124,7 +137,7 @@ pub fn make_singleton_server(
 	});
 	RpcServer {
 		shutdown_broadcast,
-		current_name,
+		current_status,
 		fut,
 	}
 }
@@ -139,8 +152,11 @@ pub async fn start_singleton_server<'a>(
 
 	{
 		print_listening(&args.log, &args.tunnel.name);
-		let mut name = args.server.current_name.lock().unwrap();
-		*name = Some(args.tunnel.name.clone())
+		let mut status = args.server.current_status.lock().unwrap();
+		*status = Some(StatusInfo {
+			name: args.tunnel.name.clone(),
+			lock: args.tunnel.status(),
+		})
 	}
 
 	let serve_fut = super::serve(