feat(fs): add the `size` method to get the size of a file or directory (#2095)

.changes/add-fs-size.md

@@ -0,0 +1,5 @@
+---
+fs: minor
+---
+
+Add the `size` method to get the size of a file or directory.

plugins/fs/build.rs

@@ -102,6 +102,7 @@ const COMMANDS: &[(&str, &[&str])] = &[
     ("exists", &[]),
     ("watch", &[]),
     ("unwatch", &[]),
+    ("size", &[]),
 ];
 
 fn main() {

plugins/fs/guest-js/index.ts

@@ -1322,6 +1322,31 @@ async function watchImmediate(
   }
 }
 
+/**
+ * Get the size of a file or directory. For files, the `stat` functions can be used as well.
+ *
+ * If `path` is a directory, this function will recursively iterate over every file and every directory inside of `path` and therefore will be very time consuming if used on larger directories.
+ *
+ * @example
+ * ```typescript
+ * import { size, BaseDirectory } from '@tauri-apps/plugin-fs';
+ * // Get the size of the `$APPDATA/tauri` directory.
+ * const dirSize = await size('tauri', { baseDir: BaseDirectory.AppData });
+ * console.log(dirSize); // 1024
+ * ```
+ *
+ * @since 2.1.0
+ */
+async function size(path: string | URL): Promise<number> {
+  if (path instanceof URL && path.protocol !== 'file:') {
+    throw new TypeError('Must be a file URL.')
+  }
+
+  return await invoke('plugin:fs|size', {
+    path: path instanceof URL ? path.toString() : path
+  })
+}
+
 export type {
   CreateOptions,
   OpenOptions,
@@ -1369,5 +1394,6 @@ export {
   writeTextFile,
   exists,
   watch,
-  watchImmediate
+  watchImmediate,
+  size
 }

plugins/fs/permissions/autogenerated/commands/size.toml

@@ -0,0 +1,13 @@
+# Automatically generated - DO NOT EDIT!
+
+"$schema" = "../../schemas/schema.json"
+
+[[permission]]
+identifier = "allow-size"
+description = "Enables the size command without any pre-configured scope."
+commands.allow = ["size"]
+
+[[permission]]
+identifier = "deny-size"
+description = "Denies the size command without any pre-configured scope."
+commands.deny = ["size"]

plugins/fs/permissions/autogenerated/reference.md

@@ -3410,6 +3410,32 @@ Denies the seek command without any pre-configured scope.
 <tr>
 <td>
 
+`fs:allow-size`
+
+</td>
+<td>
+
+Enables the size command without any pre-configured scope.
+
+</td>
+</tr>
+
+<tr>
+<td>
+
+`fs:deny-size`
+
+</td>
+<td>
+
+Denies the size command without any pre-configured scope.
+
+</td>
+</tr>
+
+<tr>
+<td>
+
 `fs:allow-stat`
 
 </td>

plugins/fs/permissions/read-meta.toml

@@ -3,4 +3,4 @@
 [[permission]]
 identifier = "read-meta"
 description = "This enables all index or metadata related commands without any pre-configured accessible paths."
-commands.allow = ["read_dir", "stat", "lstat", "fstat", "exists"]
+commands.allow = ["read_dir", "stat", "lstat", "fstat", "exists", "size"]

plugins/fs/permissions/schemas/schema.json

@@ -1589,6 +1589,16 @@
           "type": "string",
           "const": "deny-seek"
         },
+        {
+          "description": "Enables the size command without any pre-configured scope.",
+          "type": "string",
+          "const": "allow-size"
+        },
+        {
+          "description": "Denies the size command without any pre-configured scope.",
+          "type": "string",
+          "const": "deny-size"
+        },
         {
           "description": "Enables the stat command without any pre-configured scope.",
           "type": "string",

plugins/fs/src/commands.rs

@@ -897,6 +897,55 @@ pub fn exists<R: Runtime>(
     Ok(resolved_path.exists())
 }
 
+#[tauri::command]
+pub async fn size<R: Runtime>(
+    webview: Webview<R>,
+    global_scope: GlobalScope<Entry>,
+    command_scope: CommandScope<Entry>,
+    path: SafeFilePath,
+    options: Option<BaseOptions>,
+) -> CommandResult<u64> {
+    let resolved_path = resolve_path(
+        &webview,
+        &global_scope,
+        &command_scope,
+        path,
+        options.as_ref().and_then(|o| o.base_dir),
+    )?;
+
+    let metadata = resolved_path.metadata()?;
+
+    if metadata.is_file() {
+        Ok(metadata.len())
+    } else {
+        let size = get_dir_size(&resolved_path).map_err(|e| {
+            format!(
+                "failed to get size at path: {} with error: {e}",
+                resolved_path.display()
+            )
+        })?;
+
+        Ok(size)
+    }
+}
+
+fn get_dir_size(path: &PathBuf) -> CommandResult<u64> {
+    let mut size = 0;
+
+    for entry in std::fs::read_dir(path)? {
+        let entry = entry?;
+        let metadata = entry.metadata()?;
+
+        if metadata.is_file() {
+            size += metadata.len();
+        } else if metadata.is_dir() {
+            size += get_dir_size(&entry.path())?;
+        }
+    }
+
+    Ok(size)
+}
+
 #[cfg(not(target_os = "android"))]
 pub fn resolve_file<R: Runtime>(
     webview: &Webview<R>,

plugins/fs/src/lib.rs

@@ -417,6 +417,7 @@ pub fn init<R: Runtime>() -> TauriPlugin<R, Option<config::Config>> {
             commands::write_file,
             commands::write_text_file,
             commands::exists,
+            commands::size,
             #[cfg(feature = "watch")]
             watcher::watch,
             #[cfg(feature = "watch")]