Detect and surface plugin runtime crashes (#502)

crates/yaak-plugins/src/manager.rs

@@ -52,6 +52,9 @@ pub struct PluginManager {
     dev_mode: bool,
     /// Errors from plugin initialization, retrievable once via `take_init_errors`.
     init_errors: Arc<Mutex<Vec<(String, String)>>>,
+    /// Set to the exit status if the runtime dies unexpectedly, observable
+    /// via `runtime_crash_rx`.
+    runtime_crash_rx: tokio::sync::watch::Receiver<Option<String>>,
 }
 
 /// Callback for plugin initialization events (e.g., toast notifications)
@@ -83,6 +86,12 @@ impl PluginManager {
 
         let (client_disconnect_tx, mut client_disconnect_rx) = mpsc::channel(128);
         let (client_connect_tx, mut client_connect_rx) = tokio::sync::watch::channel(false);
+        // Set to the exit status if the runtime dies unexpectedly. The app is
+        // still usable without the plugin runtime (just missing features), so
+        // this unblocks startup and is surfaced to the user rather than
+        // taking the app down.
+        let (unexpected_exit_tx, unexpected_exit_rx) =
+            tokio::sync::watch::channel::<Option<String>>(None);
         let ws_service =
             PluginRuntimeServerWebsocket::new(events_tx, client_disconnect_tx, client_connect_tx);
 
@@ -96,6 +105,7 @@ impl PluginManager {
             installed_plugin_dir,
             dev_mode,
             init_errors: Default::default(),
+            runtime_crash_rx: unexpected_exit_rx.clone(),
         };
 
         // Forward events to subscribers
@@ -132,16 +142,22 @@ impl PluginManager {
         let listener = TcpListener::bind(listen_addr).await.expect("Failed to bind TCP listener");
         let addr = listener.local_addr().expect("Failed to get local address");
 
-        // 1. Wait for Node.js runtime to connect
+        // 1. Wait for the Node.js runtime to connect, or for it to die trying
+        let mut init_dead_rx = unexpected_exit_rx.clone();
         let init_plugins_task = tokio::spawn(async move {
-            match client_connect_rx.changed().await {
-                Ok(_) => {
-                    info!("Plugin runtime client connected!");
-                    // Note: initialize_all_plugins is now called separately by the app
-                    // after setting up the plugin list
-                }
-                Err(e) => {
-                    warn!("Failed to receive from client connection rx {e:?}");
+            tokio::select! {
+                result = client_connect_rx.changed() => match result {
+                    Ok(_) => {
+                        info!("Plugin runtime client connected!");
+                        // Note: initialize_all_plugins is now called separately by the app
+                        // after setting up the plugin list
+                    }
+                    Err(e) => {
+                        warn!("Failed to receive from client connection rx {e:?}");
+                    }
+                },
+                _ = init_dead_rx.wait_for(|status| status.is_some()) => {
+                    warn!("Plugin runtime exited before connecting; continuing without plugins");
                 }
             }
         });
@@ -159,11 +175,17 @@ impl PluginManager {
             addr,
             &kill_server_rx,
             killed_tx,
+            unexpected_exit_tx,
         )
         .await?;
         info!("Waiting for plugins to initialize");
         init_plugins_task.await.map_err(|e| PluginErr(e.to_string()))?;
 
+        if unexpected_exit_rx.borrow().is_some() {
+            warn!("Skipping plugin initialization because the runtime is not running");
+            return Ok(plugin_manager);
+        }
+
         let bundled_dirs = plugin_manager.list_bundled_plugin_dirs().await?;
         let db = query_manager.connect();
         for dir in &bundled_dirs {
@@ -201,6 +223,12 @@ impl PluginManager {
         std::mem::take(&mut *self.init_errors.lock().await)
     }
 
+    /// A receiver that is set to the exit status if the plugin runtime dies
+    /// unexpectedly.
+    pub fn runtime_crash_rx(&self) -> tokio::sync::watch::Receiver<Option<String>> {
+        self.runtime_crash_rx.clone()
+    }
+
     /// Get the vendored plugin directory path (resolves dev mode path if applicable)
     pub fn get_plugins_dir(&self) -> PathBuf {
         if self.dev_mode {

crates/yaak-plugins/src/nodejs.rs

@@ -1,5 +1,5 @@
 use crate::error::Result;
-use log::{info, warn};
+use log::{error, info, warn};
 use std::net::SocketAddr;
 use std::path::Path;
 use std::process::Stdio;
@@ -15,12 +15,16 @@ use yaak_common::command::new_xplatform_command;
 /// * `plugin_runtime_main` - Path to the plugin runtime index.cjs
 /// * `addr` - Socket address for the plugin runtime to connect to
 /// * `kill_rx` - Channel to signal shutdown
+/// * `killed_tx` - Notified once the runtime is killed after a shutdown signal
+/// * `unexpected_exit_tx` - Set to the exit status if the runtime exits
+///   without being asked to
 pub async fn start_nodejs_plugin_runtime(
     node_bin_path: &Path,
     plugin_runtime_main: &Path,
     addr: SocketAddr,
     kill_rx: &Receiver<bool>,
     killed_tx: oneshot::Sender<()>,
+    unexpected_exit_tx: tokio::sync::watch::Sender<Option<String>>,
 ) -> Result<()> {
     // HACK: Remove UNC prefix for Windows paths to pass to sidecar
     let plugin_runtime_main_str =
@@ -65,18 +69,29 @@ pub async fn start_nodejs_plugin_runtime(
         });
     }
 
-    // Handle kill signal
+    // Wait for either an explicit kill signal or the child exiting on its own.
+    // An unexpected exit is reported to the caller, which decides whether to
+    // abort startup or surface a user-facing error.
     let mut kill_rx = kill_rx.clone();
     tokio::spawn(async move {
-        if kill_rx.wait_for(|b| *b == true).await.is_err() {
-            warn!("Kill channel closed before explicit shutdown; terminating plugin runtime");
+        tokio::select! {
+            status = child.wait() => {
+                let status = status.map(|s| s.to_string()).unwrap_or_else(|e| e.to_string());
+                error!("Plugin runtime exited unexpectedly ({status})");
+                let _ = unexpected_exit_tx.send(Some(status));
+            }
+            closed = async { kill_rx.wait_for(|b| *b == true).await.is_err() } => {
+                if closed {
+                    warn!("Kill channel closed before explicit shutdown; terminating plugin runtime");
+                }
+                info!("Killing plugin runtime");
+                if let Err(e) = child.kill().await {
+                    warn!("Failed to kill plugin runtime: {e}");
+                }
+                info!("Killed plugin runtime");
+                let _ = killed_tx.send(());
+            }
         }
-        info!("Killing plugin runtime");
-        if let Err(e) = child.kill().await {
-            warn!("Failed to kill plugin runtime: {e}");
-        }
-        info!("Killed plugin runtime");
-        let _ = killed_tx.send(());
     });
 
     Ok(())