fix(updater): check for updates on Linux deb/rpm installs and prompt manual download (#604)

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

crates-tauri/yaak-app-client/src/updates.rs

@@ -76,14 +76,6 @@ impl YaakUpdater {
         auto_download: bool,
         update_trigger: UpdateTrigger,
     ) -> Result<bool> {
-        // Only AppImage supports updates on Linux, so skip if it's not
-        #[cfg(target_os = "linux")]
-        {
-            if std::env::var("APPIMAGE").is_err() {
-                return Ok(false);
-            }
-        }
-
         let settings = window.db().get_settings();
         let update_key = format!("{:x}", md5::compute(settings.id));
         self.last_check = Some(Instant::now());
@@ -130,6 +122,18 @@ impl YaakUpdater {
             Some(update) => {
                 let w = window.clone();
                 tauri::async_runtime::spawn(async move {
+                    // Only hand the artifact to the updater plugin when this install can
+                    // apply it itself; otherwise tell the user how to update instead
+                    let install = update_install_method(&update);
+                    if install != UpdateInstall::Integrated {
+                        info!(
+                            "{} available, but this install updates via {install:?}",
+                            update.version
+                        );
+                        notify_external_update(&w, &update, install);
+                        return;
+                    }
+
                     // Force native updater if specified (useful if a release broke the UI)
                     let native_install_mode =
                         update.raw_json.get("install_mode").map(|v| v.as_str()).unwrap_or_default()
@@ -207,6 +211,23 @@ struct UpdateInfo {
     reply_event_id: String,
     version: String,
     downloaded: bool,
+    /// How this update gets applied. Anything but `Integrated` means the app can't do it
+    /// itself and the user is told how to update instead.
+    install: UpdateInstall,
+}
+
+/// How an update can be applied to this install.
+#[derive(Debug, Clone, Copy, PartialEq, Serialize, Default, TS)]
+#[serde(rename_all = "snake_case")]
+#[ts(export, export_to = "index.ts")]
+enum UpdateInstall {
+    /// The app downloads and installs it itself
+    #[default]
+    Integrated,
+    /// Flatpak install: updated by `flatpak update` from its remote (e.g. FlatPark)
+    Flatpak,
+    /// Nothing can install it in-app (distro package, Nix, unknown); download by hand
+    Manual,
 }
 
 #[derive(Debug, Clone, PartialEq, Deserialize, TS)]
@@ -272,8 +293,12 @@ async fn start_integrated_update<R: Runtime>(
     let _guard = Unlisten { win: window, id: event_id };
 
     // 2) Emit the event now that listener is in place
-    let info =
-        UpdateInfo { version: update.version.to_string(), downloaded, reply_event_id: reply_id };
+    let info = UpdateInfo {
+        version: update.version.to_string(),
+        downloaded,
+        install: UpdateInstall::Integrated,
+        reply_event_id: reply_id,
+    };
     window
         .emit_to(window.label(), "update_available", &info)
         .map_err(|e| GenericError(format!("Failed to emit update_available: {e}")))?;
@@ -306,6 +331,24 @@ async fn start_integrated_update<R: Runtime>(
     }
 }
 
+/// Tell the frontend about an update this install can't apply itself, so the user can be
+/// told how to get it. Unlike the integrated flow, there is nothing to reply to.
+fn notify_external_update<R: Runtime>(
+    window: &WebviewWindow<R>,
+    update: &Update,
+    install: UpdateInstall,
+) {
+    let info = UpdateInfo {
+        version: update.version.to_string(),
+        downloaded: false,
+        install,
+        reply_event_id: generate_id(),
+    };
+    if let Err(e) = window.emit_to(window.label(), "update_available", &info) {
+        warn!("Failed to emit update_available: {e}");
+    }
+}
+
 async fn start_native_update<R: Runtime>(window: &WebviewWindow<R>, update: &Update) {
     // If the frontend doesn't respond, fallback to native dialogs
     let confirmed = window
@@ -376,7 +419,137 @@ fn detect_install_mode() -> Option<&'static str> {
         return Some("nsis");
     }
     #[allow(unreachable_code)]
-    None
+    if !cfg!(target_os = "linux") {
+        None
+    } else if is_flatpak() {
+        Some("flatpak")
+    } else {
+        linux_installer()
+    }
+}
+
+/// Flatpak installs (e.g. FlatPark) are updated by flatpak from their remote; the in-app
+/// updater can't write inside the sandbox and must not try.
+fn is_flatpak() -> bool {
+    std::env::var_os("FLATPAK_ID").is_some()
+}
+
+/// How Yaak was installed on Linux, as far as the updater plugin can install into it.
+///
+/// The bundle type is stamped into the binary by the bundler, but that only says how the
+/// binary was *packaged*: third-party packages (AUR, Nix, ...) repackage the .deb, and
+/// letting dpkg/rpm replace those would stomp on another package manager's files. So a
+/// deb/rpm install also has to be one the package manager actually owns. The AppImage
+/// updater needs `$APPIMAGE` since that's the file it replaces.
+fn linux_installer() -> Option<&'static str> {
+    use tauri::utils::{config::BundleType, platform::bundle_type};
+    match bundle_type() {
+        Some(BundleType::Deb) if package_manager_owns_exe("dpkg", "-S") => Some("deb"),
+        Some(BundleType::Rpm) if package_manager_owns_exe("rpm", "-qf") => Some("rpm"),
+        Some(BundleType::Deb) | Some(BundleType::Rpm) => None,
+        _ if std::env::var_os("APPIMAGE").is_some() => Some("appimage"),
+        _ => None,
+    }
+}
+
+/// Whether `cmd query_arg <current exe>` succeeds, i.e. that package manager knows the
+/// running executable as one of its files. False when the tool isn't installed at all.
+fn package_manager_owns_exe(cmd: &str, query_arg: &str) -> bool {
+    let Ok(exe) = std::env::current_exe() else {
+        return false;
+    };
+    std::process::Command::new(cmd)
+        .arg(query_arg)
+        .arg(&exe)
+        .stdin(std::process::Stdio::null())
+        .stdout(std::process::Stdio::null())
+        .stderr(std::process::Stdio::null())
+        .status()
+        .map(|status| status.success())
+        .unwrap_or(false)
+}
+
+/// How the artifact the server returned can be applied to this install. On Linux the
+/// server may hand back a different package format than the one installed, Flatpak can't
+/// be written from inside the sandbox, and unknown install methods (distro packages,
+/// Nix, ...) can't be updated in-app at all.
+fn update_install_method(update: &Update) -> UpdateInstall {
+    // Dev-only override to preview the non-integrated flows on any OS:
+    //   YAAK_SIMULATE_INSTALL=flatpak|manual
+    if is_dev() {
+        match std::env::var("YAAK_SIMULATE_INSTALL").as_deref() {
+            Ok("flatpak") => return UpdateInstall::Flatpak,
+            Ok("manual") => return UpdateInstall::Manual,
+            _ => {}
+        }
+    }
+
+    if !cfg!(target_os = "linux") {
+        return UpdateInstall::Integrated;
+    }
+    if is_flatpak() {
+        return UpdateInstall::Flatpak;
+    }
+    if artifact_matches_installer(linux_installer(), update.download_url.path()) {
+        UpdateInstall::Integrated
+    } else {
+        UpdateInstall::Manual
+    }
+}
+
+/// Whether the artifact at `url_path` is in the package format `installer` can install.
+fn artifact_matches_installer(installer: Option<&str>, url_path: &str) -> bool {
+    let path = url_path.to_ascii_lowercase();
+    match installer {
+        Some("deb") => path.ends_with(".deb"),
+        Some("rpm") => path.ends_with(".rpm"),
+        Some("appimage") => path.ends_with(".appimage") || path.ends_with(".appimage.tar.gz"),
+        _ => false,
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::artifact_matches_installer;
+
+    const BASE: &str = "/mountain-loop/yaak/releases/download/v2026.6.0/";
+
+    #[test]
+    fn matching_package_format_is_installable() {
+        let cases = [
+            ("deb", "yaak_2026.6.0_amd64.deb"),
+            ("deb", "yaak_2026.6.0_arm64.deb"),
+            ("rpm", "yaak-2026.6.0-1.x86_64.rpm"),
+            ("rpm", "yaak-2026.6.0-1.aarch64.rpm"),
+            ("appimage", "yaak_2026.6.0_amd64.AppImage"),
+            ("appimage", "yaak_2026.6.0_amd64.AppImage.tar.gz"),
+        ];
+        for (installer, asset) in cases {
+            assert!(
+                artifact_matches_installer(Some(installer), &format!("{BASE}{asset}")),
+                "{installer} should install {asset}"
+            );
+        }
+    }
+
+    #[test]
+    fn mismatched_package_format_is_not_installable() {
+        // What the server returns for every Linux install today
+        let appimage = format!("{BASE}yaak_2026.6.0_amd64.AppImage");
+        assert!(!artifact_matches_installer(Some("deb"), &appimage));
+        assert!(!artifact_matches_installer(Some("rpm"), &appimage));
+
+        let deb = format!("{BASE}yaak_2026.6.0_amd64.deb");
+        assert!(!artifact_matches_installer(Some("rpm"), &deb));
+        assert!(!artifact_matches_installer(Some("appimage"), &deb));
+    }
+
+    #[test]
+    fn unknown_installer_is_never_installable() {
+        for asset in ["yaak_2026.6.0_amd64.deb", "yaak_2026.6.0_amd64.AppImage"] {
+            assert!(!artifact_matches_installer(None, &format!("{BASE}{asset}")));
+        }
+    }
 }
 
 pub async fn install_update_maybe_download<R: Runtime>(