🐛 fix stale desktop lock recovery (#33)

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Reverier Xu <reverier.xu@xdsec.club>

Author: 3 people

crates/desktop/src/launcher.rs

@@ -1,4 +1,5 @@
-use async_compat::Compat;
+use std::{path::Path, time::Duration};
+
 use directories::ProjectDirs;
 use slint::PlatformError;
 use tracing::info;
@@ -17,33 +18,7 @@ pub fn setup() -> Result<MainWindow, PlatformError> {
     };
     let lock_file = proj_dirs.data_local_dir().join(".rx.is.alive");
 
-    if lock_file.exists() {
-        eprintln!("Another instance of the application is already running.");
-        let api_port = std::fs::read_to_string(&lock_file).unwrap_or_else(|_| {
-            eprintln!("Failed to read lock file");
-            std::fs::remove_file(&lock_file).unwrap_or_else(|_| {
-                eprintln!("Failed to remove lock file");
-            });
-            std::process::exit(1);
-        });
-        eprintln!("Notify the other instance to raise...");
-        slint::spawn_local(Compat::new(async move {})).expect("Failed to spawn thread");
-        let client = reqwest::blocking::Client::new();
-        match client
-            .post(format!("http://127.0.0.1:{api_port}/popup"))
-            .header("User-Agent", format!("wsrx/{}", env!("CARGO_PKG_VERSION")))
-            .send()
-        {
-            Ok(_) => {
-                eprintln!("Notification sent.");
-            }
-            Err(e) => {
-                eprintln!("Failed to send notification: {e}, removing lock file.");
-                std::fs::remove_file(&lock_file).unwrap_or_else(|_| {
-                    eprintln!("Failed to remove lock file");
-                });
-            }
-        }
+    if lock_file.exists() && try_focus_existing_instance(&lock_file) {
         std::process::exit(0);
     }
 
@@ -64,10 +39,82 @@ pub fn setup() -> Result<MainWindow, PlatformError> {
     Ok(ui)
 }
 
-pub fn shutdown(ui: &slint::Weak<MainWindow>) {
-    let window = ui.upgrade().unwrap();
-    bridges::settings::save_config(&window);
-    daemon::save_scopes(ui);
+fn try_focus_existing_instance(lock_file: &Path) -> bool {
+    eprintln!("Detected existing instance lock file. Trying to notify running app...");
+
+    let Some(api_port) = read_lock_file_port(lock_file) else {
+        return false;
+    };
+
+    match notify_existing_instance(api_port) {
+        Ok(()) => {
+            eprintln!("Notification sent.");
+            true
+        }
+        Err(err) => {
+            eprintln!("Failed to notify existing app: {err}. Removing stale lock file.");
+            remove_lock_file(lock_file);
+            false
+        }
+    }
+}
+
+fn remove_lock_file(lock_file: &Path) {
+    std::fs::remove_file(lock_file).unwrap_or_else(|err| {
+        if err.kind() != std::io::ErrorKind::NotFound {
+            eprintln!("Failed to remove lock file: {err}");
+        }
+    });
+}
+
+fn read_lock_file_port(lock_file: &Path) -> Option<u16> {
+    match std::fs::read_to_string(lock_file) {
+        Ok(port) => match port.trim().parse::<u16>() {
+            Ok(port) => Some(port),
+            Err(err) => {
+                eprintln!("Invalid lock file content: {err}. Removing stale lock file.");
+                remove_lock_file(lock_file);
+                None
+            }
+        },
+        Err(err) => {
+            eprintln!("Failed to read lock file: {err}. Removing stale lock file.");
+            remove_lock_file(lock_file);
+            None
+        }
+    }
+}
+
+fn notify_existing_instance(api_port: u16) -> Result<(), String> {
+    let client = reqwest::blocking::Client::builder()
+        .no_proxy()
+        .timeout(Duration::from_secs(2))
+        .build()
+        .unwrap_or_else(|err| {
+            eprintln!(
+                "Failed to create loopback HTTP client: {err}. Falling back to default client."
+            );
+            reqwest::blocking::Client::new()
+        });
+
+    let response = client
+        .post(format!("http://127.0.0.1:{api_port}/popup"))
+        .header("User-Agent", format!("wsrx/{}", env!("CARGO_PKG_VERSION")))
+        .send()
+        .map_err(|err| err.to_string())?;
+
+    if response.status().is_success() {
+        Ok(())
+    } else {
+        Err(format!("unexpected response status {}", response.status()))
+    }
+}
+
+pub fn cleanup_runtime_state(ui: &slint::Weak<MainWindow>) {
+    if let Some(window) = ui.upgrade() {
+        bridges::settings::save_config(&window);
+        daemon::save_scopes(ui);
+    }
 
     let proj_dirs = match ProjectDirs::from("org", "xdsec", "wsrx") {
         Some(dirs) => dirs,
@@ -77,15 +124,20 @@ pub fn shutdown(ui: &slint::Weak<MainWindow>) {
         }
     };
 
-    let log_dir = proj_dirs.data_local_dir().join("logs");
+    cleanup_runtime_files(proj_dirs.data_local_dir());
+}
+
+pub fn shutdown(ui: &slint::Weak<MainWindow>) {
+    cleanup_runtime_state(ui);
+    std::process::exit(0);
+}
+
+fn cleanup_runtime_files(data_local_dir: &Path) {
+    let log_dir = data_local_dir.join("logs");
     std::fs::remove_dir_all(log_dir).unwrap_or_else(|_| {
         eprintln!("Failed to remove log directory");
     });
 
-    let lock_file = proj_dirs.data_local_dir().join(".rx.is.alive");
-    std::fs::remove_file(lock_file).unwrap_or_else(|_| {
-        eprintln!("Failed to remove lock file");
-    });
-
-    std::process::exit(0);
+    let lock_file = data_local_dir.join(".rx.is.alive");
+    remove_lock_file(&lock_file);
 }

crates/desktop/src/main.rs

@@ -31,9 +31,11 @@ fn main() -> Result<(), Box<dyn Error>> {
 
     // Create the main window.
     let ui = launcher::setup()?;
+    let ui_weak = ui.as_weak();
     ui.run().ok();
-    drop(console_guard);
+    launcher::cleanup_runtime_state(&ui_weak);
     drop(file_guard);
+    drop(console_guard);
     drop(ui);
 
     Ok(())