fix(single-instance): unconventional dbus names (fixes #3184) (#3194)

Co-authored-by: FabianLars <github@fabianlars.de>
Co-authored-by: Amr Bashir <github@amrbashir.me>

.changes/fix-unconventional-dbus-names.md

@@ -0,0 +1,9 @@
+---
+"single-instance": minor:fix
+---
+
+**Breaking Change:** On Linux, the DBus ID/name will now be `<bundle-id>.SingleInstance` instead of `org.<bundle_id_underscores>.SingleInstance` to follow DBus specifications.
+
+This will break the single-instance mechanism across different app versions if the app was installed multiple times.
+
+Added `dbus_id` builder method, which can be used to restore previous behavior. For a bundle identifier of `com.tauri.my-example` this would be `dbus_id("org.com_tauri_my_example")`.

.gitignore

@@ -21,6 +21,7 @@ target/
 package-lock.json
 yarn.lock
 bun.lockb
+bun.lock
 
 # rust compiled folders
 target/

plugins/single-instance/README.md

@@ -59,6 +59,10 @@ fn main() {
 
 Note that currently, plugins run in the order they were added in to the builder, so make sure that this plugin is registered first.
 
+## Usage with Flatpak/Snap
+
+If you use Flatpak/Snap to publish your package and your Tauri identifier doesn't match the package id, set the `DBUS_ID` variable using the builder for the plugin, look at example.
+
 ## Contributing
 
 PRs accepted. Please make sure to read the Contributing Guide before making a pull request.

plugins/single-instance/examples/vanilla/src-tauri/src/main.rs

@@ -9,9 +9,14 @@
 
 fn main() {
     tauri::Builder::default()
-        .plugin(tauri_plugin_single_instance::init(|app, argv, cwd| {
-            println!("{}, {argv:?}, {cwd}", app.package_info().name);
-        }))
+        .plugin(
+            tauri_plugin_single_instance::Builder::new()
+                .callback(move |app, argv, cwd| {
+                    println!("{}, {argv:?}, {cwd}", app.package_info().name);
+                })
+                .dbus_id("org.Tauri.SIExampleApp".to_owned())
+                .build(),
+        )
         .run(tauri::generate_context!())
         .expect("error while running tauri application");
 }

plugins/single-instance/src/lib.rs

@@ -29,17 +29,70 @@ pub(crate) type SingleInstanceCallback<R> =
     dyn FnMut(&AppHandle<R>, Vec<String>, String) + Send + Sync + 'static;
 
 pub fn init<R: Runtime, F: FnMut(&AppHandle<R>, Vec<String>, String) + Send + Sync + 'static>(
-    mut f: F,
+    f: F,
 ) -> TauriPlugin<R> {
-    platform_impl::init(Box::new(move |app, args, cwd| {
-        #[cfg(feature = "deep-link")]
-        if let Some(deep_link) = app.try_state::<tauri_plugin_deep_link::DeepLink<R>>() {
-            deep_link.handle_cli_arguments(args.iter());
-        }
-        f(app, args, cwd)
-    }))
+    Builder::new().callback(f).build()
 }
 
 pub fn destroy<R: Runtime, M: Manager<R>>(manager: &M) {
     platform_impl::destroy(manager)
 }
+
+pub struct Builder<R: Runtime> {
+    callback: Box<SingleInstanceCallback<R>>,
+    dbus_id: Option<String>,
+}
+
+impl<R: Runtime> Default for Builder<R> {
+    fn default() -> Self {
+        Self {
+            callback: Box::new(move |_app, _args, _| {
+                #[cfg(feature = "deep-link")]
+                if let Some(deep_link) = _app.try_state::<tauri_plugin_deep_link::DeepLink<R>>() {
+                    deep_link.handle_cli_arguments(_args.iter());
+                }
+            }),
+            dbus_id: None,
+        }
+    }
+}
+
+impl<R: Runtime> Builder<R> {
+    pub fn new() -> Self {
+        Default::default()
+    }
+
+    /// Function to call when a secondary instance was opened by the user and killed by the plugin.
+    /// If the `deep-link` feature is enabled, the plugin triggers the deep-link plugin before executing the callback.
+    pub fn callback<F: FnMut(&AppHandle<R>, Vec<String>, String) + Send + Sync + 'static>(
+        mut self,
+        mut f: F,
+    ) -> Self {
+        self.callback = Box::new(move |app, args, cwd| {
+            #[cfg(feature = "deep-link")]
+            if let Some(deep_link) = app.try_state::<tauri_plugin_deep_link::DeepLink<R>>() {
+                deep_link.handle_cli_arguments(args.iter());
+            }
+            f(app, args, cwd)
+        });
+        self
+    }
+
+    /// Set a custom D-Bus ID, used on Linux. The plugin will append a `.SingleInstance` subname.
+    /// For example `com.mycompany.myapp` will result in the plugin registering its D-Bus service on `com.mycompany.myapp.SingleInstance`.
+    /// Usually you want the same base ID across all components in your app.
+    ///
+    /// Defaults to the app's bundle identifier set in tauri.conf.json.
+    pub fn dbus_id(mut self, dbus_id: impl Into<String>) -> Self {
+        self.dbus_id = Some(dbus_id.into());
+        self
+    }
+
+    pub fn build(self) -> TauriPlugin<R> {
+        platform_impl::init(
+            self.callback,
+            #[cfg(target_os = "linux")]
+            self.dbus_id,
+        )
+    }
+}

plugins/single-instance/src/platform_impl/linux.rs

@@ -8,12 +8,9 @@ use crate::semver_compat::semver_compat_string;
 use crate::SingleInstanceCallback;
 use tauri::{
     plugin::{self, TauriPlugin},
-    AppHandle, Config, Manager, RunEvent, Runtime,
-};
-use zbus::{
-    blocking::{connection::Builder, Connection},
-    interface,
+    AppHandle, Manager, RunEvent, Runtime,
 };
+use zbus::{blocking::Connection, interface, names::WellKnownName};
 
 struct ConnectionHandle(Connection);
 
@@ -29,35 +26,31 @@ impl<R: Runtime> SingleInstanceDBus<R> {
     }
 }
 
-#[cfg(feature = "semver")]
-fn dbus_id(config: &Config, version: semver::Version) -> String {
-    let mut id = config.identifier.replace(['.', '-'], "_");
-    id.push('_');
-    id.push_str(semver_compat_string(version).as_str());
-    id
-}
+struct DBusName(String);
 
-#[cfg(not(feature = "semver"))]
-fn dbus_id(config: &Config) -> String {
-    config.identifier.replace(['.', '-'], "_")
-}
-
-pub fn init<R: Runtime>(f: Box<SingleInstanceCallback<R>>) -> TauriPlugin<R> {
+pub fn init<R: Runtime>(
+    callback: Box<SingleInstanceCallback<R>>,
+    dbus_id: Option<String>,
+) -> TauriPlugin<R> {
     plugin::Builder::new("single-instance")
-        .setup(|app, _api| {
+        .setup(move |app, _api| {
+            let mut dbus_name = dbus_id.unwrap_or_else(|| app.config().identifier.clone());
+            dbus_name.push_str(".SingleInstance");
+
             #[cfg(feature = "semver")]
-            let id = dbus_id(app.config(), app.package_info().version.clone());
-            #[cfg(not(feature = "semver"))]
-            let id = dbus_id(app.config());
+            {
+                dbus_name.push('_');
+                dbus_name.push_str(semver_compat_string(&app.package_info().version).as_str());
+            }
+
+            let dbus_path = dbus_name.replace('.', "/");
 
             let single_instance_dbus = SingleInstanceDBus {
-                callback: f,
+                callback,
                 app_handle: app.clone(),
             };
-            let dbus_name = format!("org.{id}.SingleInstance");
-            let dbus_path = format!("/org/{id}/SingleInstance");
 
-            match Builder::session()
+            match zbus::blocking::connection::Builder::session()
                 .unwrap()
                 .name(dbus_name.as_str())
                 .unwrap()
@@ -92,9 +85,11 @@ pub fn init<R: Runtime>(f: Box<SingleInstanceCallback<R>>) -> TauriPlugin<R> {
                 _ => {}
             }
 
+            app.manage(DBusName(dbus_name));
+
             Ok(())
         })
-        .on_event(|app, event| {
+        .on_event(move |app, event| {
             if let RunEvent::Exit = event {
                 destroy(app);
             }
@@ -104,15 +99,11 @@ pub fn init<R: Runtime>(f: Box<SingleInstanceCallback<R>>) -> TauriPlugin<R> {
 
 pub fn destroy<R: Runtime, M: Manager<R>>(manager: &M) {
     if let Some(connection) = manager.try_state::<ConnectionHandle>() {
-        #[cfg(feature = "semver")]
-        let id = dbus_id(
-            manager.config(),
-            manager.app_handle().package_info().version.clone(),
-        );
-        #[cfg(not(feature = "semver"))]
-        let id = dbus_id(manager.config());
-
-        let dbus_name = format!("org.{id}.SingleInstance",);
-        let _ = connection.0.release_name(dbus_name);
+        if let Some(dbus_name) = manager
+            .try_state::<DBusName>()
+            .and_then(|name| WellKnownName::try_from(name.0.clone()).ok())
+        {
+            let _ = connection.0.release_name(dbus_name);
+        }
     }
 }

plugins/single-instance/src/platform_impl/macos.rs

@@ -63,7 +63,7 @@ fn socket_path(config: &Config, _package_info: &tauri::PackageInfo) -> PathBuf {
     #[cfg(feature = "semver")]
     let identifier = format!(
         "{identifier}_{}",
-        semver_compat_string(_package_info.version.clone()),
+        semver_compat_string(&_package_info.version),
     );
 
     // Use /tmp as socket path must be shorter than 100 chars.

plugins/single-instance/src/platform_impl/windows.rs

@@ -59,7 +59,7 @@ pub fn init<R: Runtime>(callback: Box<SingleInstanceCallback<R>>) -> TauriPlugin
             #[cfg(feature = "semver")]
             {
                 id.push('_');
-                id.push_str(semver_compat_string(app.package_info().version.clone()).as_str());
+                id.push_str(semver_compat_string(&app.package_info().version).as_str());
             }
 
             let class_name = encode_wide(format!("{id}-sic"));

plugins/single-instance/src/semver_compat.rs

@@ -4,7 +4,7 @@
 
 /// Takes a version and spits out a String with trailing _x, thus only considering the digits
 /// relevant regarding semver compatibility
-pub fn semver_compat_string(version: semver::Version) -> String {
+pub fn semver_compat_string(version: &semver::Version) -> String {
     // for pre-release always treat each version separately
     if !version.pre.is_empty() {
         return version.to_string().replace(['.', '-'], "_");