perf: use native walkdir for recursive imports from directory (#2993)

* fix(perf): replace JS recursion with native Rust walkdir for imports

* fix: implement security scope check in rust recursive scanner

* refactor and format code

---------

Co-authored-by: Huang Xin <chrox.huang@gmail.com>

apps/readest-app/src-tauri/src/dir_scanner.rs

@@ -0,0 +1,96 @@
+use std::path::Path;
+use tauri::AppHandle;
+use tauri_plugin_fs::FsExt;
+use walkdir::WalkDir;
+
+#[derive(serde::Serialize)]
+pub struct ScannedFile {
+    pub path: String,
+    pub size: u64,
+}
+
+#[tauri::command]
+pub fn read_dir(
+    app: AppHandle,
+    path: String,
+    recursive: bool,
+    extensions: Vec<String>,
+) -> Result<Vec<ScannedFile>, String> {
+    let scope = app.fs_scope();
+    let path_buf = std::path::PathBuf::from(&path);
+
+    if !scope.is_allowed(&path_buf) {
+        return Err("Permission denied: Path not in filesystem scope".to_string());
+    }
+
+    let mut files = Vec::new();
+
+    let normalized_extensions: Vec<String> =
+        extensions.iter().map(|ext| ext.to_lowercase()).collect();
+
+    if recursive {
+        for entry_result in WalkDir::new(&path).into_iter() {
+            match entry_result {
+                Ok(entry) => {
+                    if entry.file_type().is_file() {
+                        if let Some(scanned_file) =
+                            process_file_entry(entry.path(), &normalized_extensions)
+                        {
+                            files.push(scanned_file);
+                        }
+                    }
+                }
+                Err(e) => {
+                    log::warn!("RUST: Skipping file due to error: {}", e);
+                }
+            }
+        }
+    } else {
+        match std::fs::read_dir(&path_buf) {
+            Ok(entries) => {
+                for entry_result in entries {
+                    match entry_result {
+                        Ok(entry) => {
+                            let path = entry.path();
+                            if path.is_file() {
+                                if let Some(scanned_file) =
+                                    process_file_entry(&path, &normalized_extensions)
+                                {
+                                    files.push(scanned_file);
+                                }
+                            }
+                        }
+                        Err(e) => {
+                            log::warn!("RUST: Skipping entry due to error: {}", e);
+                        }
+                    }
+                }
+            }
+            Err(e) => {
+                return Err(format!("Failed to read directory: {}", e));
+            }
+        }
+    }
+
+    Ok(files)
+}
+
+fn process_file_entry(path: &Path, extensions: &[String]) -> Option<ScannedFile> {
+    if extensions.is_empty() || extensions.contains(&"*".to_string()) {
+        let size = std::fs::metadata(path).map(|m| m.len()).unwrap_or(0);
+        return Some(ScannedFile {
+            path: path.to_string_lossy().to_string(),
+            size,
+        });
+    } else if let Some(ext) = path.extension() {
+        let ext_str = ext.to_string_lossy().to_lowercase();
+        if extensions.contains(&ext_str) {
+            let size = std::fs::metadata(path).map(|m| m.len()).unwrap_or(0);
+            return Some(ScannedFile {
+                path: path.to_string_lossy().to_string(),
+                size,
+            });
+        }
+    }
+    None
+}

apps/readest-app/src-tauri/src/lib.rs

@@ -22,6 +22,7 @@ use tauri_plugin_fs::FsExt;
 
 #[cfg(desktop)]
 use tauri::{Listener, Url};
+mod dir_scanner;
 #[cfg(any(target_os = "macos", target_os = "windows", target_os = "linux"))]
 mod discord_rpc;
 #[cfg(target_os = "macos")]
@@ -163,6 +164,7 @@ pub fn run() {
             upload_file,
             get_environment_variable,
             get_executable_dir,
+            dir_scanner::read_dir,
             #[cfg(target_os = "macos")]
             macos::safari_auth::auth_with_safari,
             #[cfg(target_os = "macos")]